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Smartbook

CONSTRUCTION SITE, WATER AND DURABILITY

Smartbook AIRTIGHTNESS CLT or frame, blockhaus or masonry, window, beam or floor: every junction has its own product. With this Smartbook, we have translated years of realworld applications into selection criteria and proven solutions.

Smartbook TIMBER SCREWS Theory, practice, experimental campaigns: putting it all together on screws takes years of research, workshops and construction sites. We make it available to you in 70 pages that are extra catalogue. Because our experience is in your hands.

Scan the QR code to download the Smartbook rothoblaas.com

DESIGN GUIDELINES

from page 5

Careful design ensures definition of the structural system, construction details and fastening systems, taking the construction stage into account, too. Every decision made at this stage reduces critical variables on site. It is not sufficient to design only the structure and certain construction details: execution and temporary protection measures must also be planned. Long-term performance and durability depend on these choices.

CONNECTIONS

from page 17

Connections are among the most sensitive points of the structure. Moisture, standing water, corrosion, incorrect construction details and errors in the installation of fastenings can compromise durability and safety. For this reason, it is essential to identify critical connections, properly design the joint, and ensure the correct installation and inspection of fastening systems.

MEMBRANES AND TAPES

from page 71

Proper design of protection systems and airtight, watertight and vapour-control layers requires a preliminary assessment of the construction element and exposure conditions. The choice of solutions is never arbitrary and directly affects performance, flow control and the durability of the building envelope.

CONSTRUCTION DETAILS

from page 129

Key construction details – such as base connections, doors and windows, water drainage, ventilation and service penetrations – require careful design. Every discontinuity is a potential weak point. The overall performance of the system depends on the quality of workmanship.

CONSTRUCTION PROJECT EXECUTION PLANS from page 173 The transport, storage, assembly and moisture management stages are defined through construction project execution and control plans that address common critical issues: safety, performance, durability and overall build quality. The moisture management plan does not overlap with the others, but instead runs through them, influencing timing, detailing and control procedures at every stage of operation.

DESIGN GUIDELINES

DESIGN GUIDELINES Careful design ensures definition of the structural system, construction details and fastening systems, taking the construction stage into account, too. Every decision made at this stage reduces critical variables on site. It is not sufficient to design only the structure and certain construction details: execution and temporary protection measures must also be planned. Long-term performance and durability depend on these choices.

BUILDING DESIGN

from page 6

DESIGN FOR THE CONSTRUCTION STAGE

from page 10

CONSTRUCTION PROJECT EXECUTION AND SITE SUPERVISION

from page 13

DESIGN GUIDELINES | 5

BUILDING DESIGN

IDENTIFY THE STRUCTURAL SYSTEM AND THE OVERALL LOAD PATH Structural system with redundancies and alternative load paths: a local failure does not lead to global collapse. Supports and connections are designed to redistribute loads.

Structural system with isostatic behaviour or with few alternative load paths: connections assume a particularly important role in the overall structural behaviour. In these cases, greater attention is required in the design of details, moisture management and the selection of fastenings.

See further details on page 186

DESIGN THE CONNECTION DETAIL TO MANAGE WATER AND MOISTURE Joint designed to limit water ingress and standing water: continuous protection and sealing of weak points, water drainage, and the possibility of ventilation and drying.

Joint with partial or absent water management: discontinuous protection, possible water ingress and localised standing water, including geometries that encourage water pooling, lack of drainage and difficult drying conditions.

See further details on page 42

SELECT FASTENINGS SUITABLE FOR IN-SERVICE AND ON-SITE CORROSIVITY CONDITIONS For critical connections and/or humid environments: stainless steel or carbon steel with advanced coating systems (e.g. EVO). Clear specifications in the technical documentation and verified compatibility between timber, fastenings and paired metals to prevent galvanic corrosion.

Use of standard electro-galvanised coatings in non-dry conditions or in polluted or coastal environments: corrosion resistance may be insufficient. Unclear technical specifications and possible galvanic coupling.

See further details on page 18

6 | BUILDING DESIGN | DESIGN GUIDELINES

DESIGN A SUITABLE BASE CONNECTION Detail designed with the wall raised above ground level, continuous waterproofing, correct sealing, adequate slopes, effective drainage and absence of thermal bridges. Connections protected from water at the base, compliance with edge distances, construction of regular kerbs, and correct arrangement of fastenings.

Wall below ground level, or otherwise exposed to persistent moisture; missing or incorrectly installed waterproofing; presence of thermal bridges; ineffective slopes and drainage resulting in standing water. Base connections exposed to prolonged wetting, holes or plates that retain water, contact with damp concrete, galvanic coupling and failure to comply with minimum edge distances.

See further details on page 130

SELECT THE CORRECT MEMBRANE FOR VAPOUR CONTROL Membrane with an Sd value defined in accordance with the design and climatic conditions. Sd value verified through calculation to ensure hygrothermal balance and proper vapour management. Climatic conditions characterised by dry cycles help reduce the risk of condensation.

Membrane with an unsuitable or unverified Sd value. Unplanned, untaped or incorrectly executed details reduce the functionality of the assembly and increase the risk of water ingress and condensation. Extreme climatic conditions, critical positioning of membranes within the build-up and tropical climates introduce further uncertainties in predictions.

See further details on page 94

ENSURE THE AIRTIGHTNESS OF THE BUILDING ENVELOPE System designed and installed to ensure the continuity of the air barrier throughout the entire assembly. Properly sealed joints, carefully executed interfaces between elements and absence of discontinuities.

Unsealed joints, discontinuities at interfaces and untreated penetrations compromise the continuity of the air barrier and increase the risk of water ingress, interstitial condensation and loss of energy efficiency.

DESIGN GUIDELINES | BUILDING DESIGN | 7

DEFINE THE FINISHING LAYER OF THE BUILDING ENVELOPE Certified and tested membranes resistant to weathering ensure protection and durability. Controlled and limited exposure of the membrane reduces stress on tapes and improves system stability.

Products not certified for the intended use, or of poor quality, deteriorate rapidly and provide limited protection. Prolonged exposure and the risk of repeated weather events accelerate membrane degradation and increase stress on the tapes.

See further details on page 106

AVOID THERMAL BRIDGES Details designed to ensure thermal continuity through continuous insulation and effective sealing, limiting heat loss and condensation.

The presence of unassessed or poorly designed thermal bridges, interruptions in the insulation layer, and the introduction of elements that reduce the temperature within the assembly encourage condensation, with a consequent risk of material degradation.

DESIGN THE WINDOW-TO-STRUCTURE JUNCTION Detail designed according to the three-level protection principle. Continuity of watertightness, airtightness, and thermal and acoustic insulation ensures system performance. Provision of drainage and correct slopes enables effective water management and prevents moisture build-up. Window sills and shading systems already integrated into the detail during the design phase, ensuring continuity of the functional layers.

Window-to-structure junction lacking a clear three-level protection strategy. Discontinuities in seals and interfaces compromise airtightness and watertightness. Absence of drainage and adequate slopes results in standing water and moisture buildup. Window sills and shading systems not integrated into the detail create weak points.

See further details on page 140

8 | BUILDING DESIGN | DESIGN GUIDELINES

PROVIDE INTEGRATED DESIGN Plumbing and electrical systems designed and integrated within the assembly, with defined routes separated from structural elements. Service penetrations correctly sealed to ensure continuity of the air and water barrier.

Services installed without prior design planning, with improvised penetrations interrupting the continuity of the air and water barriers. Unsealed openings and incompatible materials encourage water ingress and premature deterioration.

See further details on page 166

DESIGN RAINWATER DRAINAGE Drainage system designed to ensure rapid water run-off, with correct slopes and outlets sized in accordance with regulations. Provide overflow channels and avoid recessed gutters. Ensure proper maintenance throughout the entire life cycle of the building.

Absence of adequate slopes or undersized outlets causes standing water and pooling. Failure to design critical details such as downpipes and integrated gutters reduces system functionality.

See further details on page 156

PROVIDE VENTILATED ASSEMBLIES Effective ventilation of the layers promotes Lack of ventilation, or insufficient ventiladrying and reduces the risk of condensation. tion, causes moisture build-up and accelerated material deterioration.

See further details on page 150

DESIGN GUIDELINES | BUILDING DESIGN | 9

DESIGN FOR THE CONSTRUCTION STAGE

ASSESS THE TYPE OF CONSTRUCTION ELEMENT AND WEAK POINTS Assess the risk according to the geometry and inclination of the elements, and provide solutions for water deflection, runoff, drainage and drying, ensuring that the timber remains dry or can dry rapidly. Plan site activities taking into account weather conditions and the duration of exposure to water.

Ignore exposure to weathering and water retention on elements. Horizontal surfaces, enclosed environments, complex junctions, recesses and routing for beams, as well as wall bases and endgrain sections, encourage standing water, slow down drying and increase the risk of premature deterioration of the timber.

See further details on page 72

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IDENTIFY CRITICAL CONNECTIONS Protect connections with thick steel plates, avoiding direct contact with water and preventing prolonged water pooling. Apply upper and lower protection measures and carefully implement the details along the building perimeter. Opt for inclined or vertical configurations and adopt drained, inspectable solutions separated from timber elements.

Construct connections with thick steel plates that are unprotected and poorly drained, particularly around the perimeter of the building. Provide membrane upstands without drainage paths, which encourage standing water. Design balconies, projections and curtain wall fastenings with exposed, large connections that are not adequately protected from water.

See further details on page 34

10 | DESIGN FOR THE CONSTRUCTION STAGE | DESIGN GUIDELINES

ASSESS CONSTRUCTION LOADS ON THE CONNECTION The connection is not be loaded before all its fastenings have been installed. Fastenings correctly installed and tightened. No storage or assembly loads applied to the screws; the area remains protected or the building is enclosed. Where loads are expected (storage, transport, movement of personnel on site), finish installing the connection before applying the loads.

Loading the connection on site without proper verification: even if the loads are lower than the design loads, they may be repeated or of a different nature (propping, temporary supports, storage loads). If construction-stage loads have not been assessed, or are equal to or greater than the design stresses, the risk of local overload on the screws increases. Partially installed connections.

See further details on page 186

IDENTIFY THE WEATHER WINDOW AND THE CORROSIVITY OF THE ENVIRONMENT DURING CONSTRUCTION Low probability of rain, or covered construction site, with limited and controlled exposure. Drying planned through ventilation/battening and continuous moisture control, including before closing the details. Environment located away from the sea or protected; in corrosive or humid environments, suitable protections and fastenings/ coatings are already specified. No galvanic coupling on site, or adequately managed where present.

Frequent rainfall or unmanaged weather windows: repeated wetting, difficult drying and possible standing water. Corrosive environment without adequate protective measures. Prolonged exposure of timber to highly corrosive conditions. Galvanic coupling present and not mitigated.

See further details on page 18

SELECT SITE PROTECTION MEASURES Complete protection of construction elements with correctly installed waterproof membranes. Sealing of joints and areas at risk of water ingress. Possible use of treated timber to increase the level of protection. Areas with moderate rainfall and stable thermal cycles reduce risk.

Lack of protection systems, or the use of incorrectly installed membranes, encourages water ingress and standing water. Details that do not protect timber elements or allow them to dry, together with timber having high initial moisture content, increase the risk. Persistent rainfall, snow, frequent freeze-thaw cycles and day-to-night temperature fluctuations that promote dew formation increase the risk and provide limited drying potential.

See further details on page 82

DESIGN GUIDELINES | DESIGN FOR THE CONSTRUCTION STAGE | 11

DESIGN TEMPORARY WATER DRAINAGE SYSTEMS Provide temporary deflection and drainage systems, and design adequately sealed joints and connections to prevent water ingress and standing water, promoting drying of the assemblies.

Incorrect water management, standing water in undrained areas, unsealed joints and inadequate slopes encourage water pooling and increase the risk of water ingress.

See further details under “ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS” on page 72 See further details under “RAINWATER DRAINAGE AND DEFLECTION” on page 156

DEVELOP CONSTRUCTION PROJECT EXECUTION PLANS FOR MATERIAL HANDLING ON SITE Defined and coordinated construction project execution plans for transport and lifting, storage, assembly, moisture management and safety. Roles, inspections, operational sequences, temporary protection measures, moisture monitoring and verification criteria are defined in accordance with scheduling requirements, construction details and site exposure conditions.

Construction project execution plans absent, incomplete or uncoordinated, including safety-related aspects. Moisture management, temporary protection measures, inspections, installation sequences, corrective actions and acceptance limits are not clearly defined. Long and complex construction sites significantly increase risk.

See further details on page 175

8 8

MANAGE PRE-INSTALLATION AND PREFABRICATION

Installation of the protection system off site under controlled temperatures, with correct overlaps and in a clean environment. This ensures adhesion of the sealing elements and the effectiveness of the system. Gypsum and moisture-sensitive materials used for fire protection or finishing must be installed after the roof covering is completed in order to reduce risk.

On-site installation under variable climatic conditions (cold, humidity, risk of rain) and unresolved details reduce the effectiveness of the protection system. Prefabrication of moisture-sensitive materials increases the need for protection. Contact with damp materials, or with materials having different hygrothermal behaviour, encourages rising damp.

12 | DESIGN FOR THE CONSTRUCTION STAGE | DESIGN GUIDELINES

CONSTRUCTION PROJECT EXECUTION AND SITE SUPERVISION

SELECT EXPERIENCED INSTALLERS Installers with specific experience in the assembly of timber structures and knowledge of construction project execution plans. Experience in applying installation procedures, temporary protection measures, inspections and moisture management throughout the various operational stages.

Installers without specific experience or lacking knowledge of the construction project execution plans. Errors in handling, installation or temporary protection measures may increase the risk of wetting, damage to construction details, corrosion or damage to fastenings, and loss of performance during construction.

CARRY OUT CONSTRUCTION PROJECT EXECUTION PLANS FOR MATERIAL HANDLING ON SITE Construction project execution plans correctly carried out by experienced installers: handling, storage, installation, temporary protection measures and moisture management performed in accordance with the specified procedures. Connections and airtightness/watertightness details correctly executed, with inspections carried out throughout the various operational stages.

Construction project execution plans not applied, or applied without proper control: errors in handling, storage, installation sequence or assembly may compromise temporary stability, quality of workmanship and the correct execution of connections and construction details.

See further details on page 175

CORRECTLY APPLY PROTECTION SOLUTIONS ON SITE Protection solutions correctly applied and consistent with the weather window, construction period and level of exposure. Temporary protection measures, drainage systems, seals and coverings maintained in effective condition throughout the different operational stages, with prompt inspections and interventions in the event of rain or damage.

Protection solutions absent, incomplete or not maintained during construction. Failure to manage the weather window, discontinuous or damaged protection measures, and unmanaged standing water or water ingress increase the risk of prolonged wetting, material deterioration and corrosion of connections.

See further details on page 118

DESIGN GUIDELINES | CONSTRUCTION PROJECT EXECUTION AND SITE SUPERVISION | 13

CHECK THE QUALITY OF THE INSTALLATION OF TAPES, MEMBRANES AND FOAMS Membrane installed with the correct tension, overlaps suitable for the requirements of the detail, and continuous sealing (every penetration taped, every corner properly sealed). Adhesive product selected according to function, substrate type and application temperature. Tapes applied using a roller on dry, clean and compact surfaces. Use of primer where the substrate is porous, rough or difficult. Polyurethane foam suitable for its intended function.

Membrane too tight or too loose, causing water pooling and increased vulnerability to wind. Adhesive product incompatible with the substrate, temperature or service conditions. Tape applied without pressure, or onto wet, dusty or unsuitable-temperature surfaces. Failure to manage discontinuities created during installation. Foam unsuitable for the intended function.

See further details on page 118

CORRECTLY INSTALL FASTENING SYSTEMS

Fastenings installed in accordance with instructions and design specifications: correct insertion angle, suitable screwdrivers/drills, pre-drilling or pilot holes where required, installation torque control, and installation sequence consistent with ensuring uniform stress distribution within the connections.

Incorrect installation of fasteners: screws deviating from the intended installation angle, overtorque, use of impact drivers, absence of pre-drilling where required, or incorrect installation sequences may introduce overloads, damage coatings and reduce connection performance.

See further details on page 46

14 | CONSTRUCTION PROJECT EXECUTION AND SITE SUPERVISION | DESIGN GUIDELINES

ibf | ft

N m

40 80

MONITOR, INSPECT AND MANAGE THE CONSTRUCTION SITE Construction site monitored through planned inspections and checks on moisture, temporary protection measures, drainage and correct fastening installation. Any water ingress or anomalies are identified and promptly managed before compromising connections and materials.

Insufficient monitoring or ineffective inspections: water ingress, damage to protection systems, standing water, incorrectly installed fasteners or premature failures, if not identified, encourage degradation and progressive deterioration of the connections.

See further details under “INSTALLATION AND INSPECTION OF FASTENING SYSTEMS” on page 46 See further details under “CONSTRUCTION PROJECT EXECUTION PLANS” on page 174

TEST BUILDING SERVICES BEFORE CLOSING OR ENCASING CONNECTIONS Building services tested before connections are closed, with no leaks or water ingress, or with the possibility of intervention and repair without significant damage to construction elements or connections.

Connections encased or closed without prior testing of building services: any leaks or water ingress may remain undetected, causing persistent moisture and premature deterioration.

MANAGE SERVICE PENETRATIONS AND INTEGRATIONS

Services penetrations and integrations introduced during the construction stage are properly managed, ensuring continuity of the layers, airtightness, watertightness and performance consistent with the design.

Penetrations and integrations carried out without proper detailing compromise the continuity of the layers, creating entry points for water and air and encouraging deterioration.

See further details on page 168

DESIGN GUIDELINES | CONSTRUCTION PROJECT EXECUTION AND SITE SUPERVISION | 15

CONNECTIONS

CONNECTIONS Connections are among the most sensitive points of the structure. Moisture, standing water, corrosion, incorrect construction details and errors in the installation of fastenings can compromise durability and safety. For this reason, it is essential to identify critical connections, properly design the joint, and ensure the correct installation and inspection of fastening systems.

CORROSIVITY CONDITIONS ON SITE

from page 18

CRITICAL CONNECTIONS: IDENTIFICATION AND VERIFICATION

from page 34

CONNECTION DETAILS FOR MANAGING WATER AND MOISTURE

from page 42

INSTALLATION AND INSPECTION OF FASTENING SYSTEMS

from page 46

CONNECTIONS | 17

CORROSIVITY CONDITIONS ON SITE Addressing environmental corrosivity is essential in preserving the performance of metal elements for the entire service life of the building. For this reason, corrosivity must be assessed on two different scales, or “magnifying lenses”, differing both in terms of time horizon and the conditions considered: design corrosivity and construction-stage corrosivity.

DESIGN CORROSIVITY CONDITIONS Starting from the project geolocation: • the atmospheric corrosion class is determined by superimposing the project location onto the corrosivity zoning map of the area in which the building will be constructed. The zoning may vary according to the type of metal used (bright zinc-plated carbon steel, see page 20, or stainless steel, see page 21); • subsequently, according to the exposure of the connection (and therefore the moisture conditions to which the timber will be exposed) and the wood species used, the wood corrosion class is determined; • finally, for timber-to-metal connections, material compatibility is verified in order to prevent or limit galvanic coupling.

indoor environments low condensation

> 10 km

from 10 to 3 km from 3 to 0,25 km

< 0,25 km

from the coast

Atmospheric corrosivity categories according to Fpr EN 1995-1:2025, based on ISO 9223.

SERVICE CLASS TIMBER MOISTURE CONTENT TIMBER pH AND TREATMENT

WOOD CORROSIVITY CLASS

( *)

SC1

≤ 10%

any

SC2

10% <

SC3

≤ 16%

any

16% <

SC3

≤ 20%

16% <

≤ 20%

pH > 4

pH ≤ 4

and without treatments

or treated timbers

WET

SC4

> 20%

any

Wood corrosivity categories according to Fpr EN 1995-1:2025. ( *) The WET moisture condition is defined in the NDS (USA) and CSA O86 (Canada) standards as a timber moisture content greater than 19%.

For connections in conventional buildings, it is the design corrosivity that determines the material to be used. However, corrosivity during construction may temporarily be more severe and should therefore be assessed to determine whether additional protection is required, particularly in the case of long construction periods or demanding environmental conditions. 18 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

How much do we know about screws? Theory, practice, experimental campaigns: putting it all together on screws takes years of lectures, workshops and construction sites. We make it available to you in 70 pages that are extra catalogue. Because our experience is in your hands.

Scan the QR code to download the smartbook rothoblaas.com

ZONING EXAMPLE Metallic components made of carbon steel with a zinc-based coating, exposed to the atmosphere. reference standard:

Fpr EN 1995-1:2025, based on ISO 9223

3k m

Barcelona (Spain)

Tibidabo

Park Güell

25 0m

city: Mont

C4 project location

1 km

Recommended minimum zinc base coating [CR ]

10 µm

55 µm

2 km

Atmospheric corrosion classes [CE ]

25 0m

Casa Milà

Sagrada Familia

0m 25

ELECTRO PLATED

ORGANIC COATING

110 µm

n.a.

ROTHOBLAAS RECOMMENDS

EVO COATING

20 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

ELECTROLYTIC GALVANIZING Coating consisting of a 5 to 12 µm layer of electrolytic galvanizing with Cr passivation; standard for most connectors. ORGANIC ANTI-CORROSION COATING Coloured organic-based coating that provides excellent resistance to atmospheric and wood corrosive agents in outdoor applications. C4 EVO ANTI-CORROSION COATING Inorganic-based multilayer coating with an external functional layer of about 15-20 μm in an epoxy matrix with aluminium flakes. Suitability for atmospheric corrosivity class C4 proven by RISE. C5 EVO ANTI-CORROSION COATING Multi-layer coating capable of withstanding outdoor environments classified C5 according to ISO 9223. Salt spray test (SST) exceeding 3.000 h, carried out on screws previously driven into and removed from Douglas fir.

1 km

ZONING EXAMPLE Metallic components made of stainless steel, exposed to the atmosphere. city:

reference standard:

Tallinn (Estonia)

EN 1993-1-4:2024, Annex A

CRC III

1 km

Läänemeri

project location

1 km

CRC II km

Ülemiste järv

2 km

Minimum Corrosion Resistance Class [CRC]

4 km

Recommended minimum stainless steel grade

AISI 410

ROTHOBLAAS RECOMMENDS

410 AISI

1.4301 A2 AISI 304/305

CRC I

AISI 304

AISI410 STAINLESS STEEL Martensitic stainless steel. Characterised by high mechanical properties. Suitable for outdoor applications (SC3). Of the available stainless steel types, this is the one offering the highest mechanical performance. A2 | AISI304 STAINLESS STEEL Austenitic stainless steel. It is the most common of the austenitic steels. It offers an excellent level of protection against generalised corrosion.

AISI 305

A2 | AISI305 STAINLESS STEEL Austenitic stainless steel similar to A2 | AISI304. This alloy contains slightly more carbon than 304, making it more workable in production.

III

1.4401 A4 AISI 316

AISI 316

A4 | AISI316 STAINLESS STEEL Austenitic stainless steel. The presence of molybdenum provides high resistance to generalised and crevice corrosion.

1.4439

CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 21

CORROSION DURING THE CONSTRUCTION PERIOD The longer a construction site remains open and exposed to the weather, the more likely the metals used in connections are to experience environmental conditions more aggressive than those anticipated at the design stage. Fasteners are normally designed for defined service conditions (for example, service class 1 or 2, or dry conditions). During construction, however, connections and structural elements may be directly exposed to rain, high humidity and repeated wetting and drying cycles. For this reason, corrosivity during construction may be temporarily higher than that assumed in the design.

WEATHER WINDOW AND ESTIMATED CONSTRUCTION PERIOD In simplified terms, there are two main factors: • the duration of the construction site, indicating how long the elements are exposed to environmental conditions; • the weather window, indicating the level of moisture and wetting to which the elements may be exposed. The weather window is determined by overlapping the planned construction period with the climatic data for the relevant period (rainfall, humidity and probability of weather events). This makes it possible to identify the most favourable periods for carrying out moisture-sensitive operations and to assess the actual corrosion conditions. DRY

WET

DRY

100%

250 mm

90% 80%

200 mm

70%

2 jul 138 mm

60%

2 sep 129 mm

150 mm

50% 100 mm

40% 30% 20% 10%

RAIN 50 mm

13 apr 13 mm

28 jan 8 mm

12 dic 3 mm 0 mm

0% jan

feb

mar

apr

may

jun

jul

aug

sep

oct

nov

dec

construction period Weather conditions in Mexico City during 2025. Meteoblue Weather Archive, 2026.

For the assessment of wood corrosivity, the main parameters to be considered are: mm

rainfall (mm): indicates the quantity of water potentially present on surfaces and the risk of standing water; number of rainy days: indicates the frequency of wetting cycles and the possibility for elements to dry between rainfall events; relative humidity: provides an indication of the tendency of timber to maintain a high moisture content for prolonged periods and therefore to fall within a specific wood corrosivity category.

In particular, the weather window indicates the level of moisture to which timber and connections may be exposed during construction. This affects both atmospheric corrosivity, which is generally better known and already considered in material selection, and, above all, wood corrosivity, namely the moisture conditions in the material that may accelerate the corrosion of fasteners embedded within. 22 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

SELECTION OF PROTECTIVE MEASURES ON SITE The severity resulting from the combination of the weather window and construction period may influence the choice of protective measures (see the chapter “SITE PROTECTION: SYSTEM SELECTION” on page 82). In practice, for small and medium-sized sites with favourable weather windows, localised measures are often sufficient. Temporary surface coverings are becoming increasingly widespread because they provide protection while allowing greater flexibility during construction activities, whereas side coverings are particularly useful where rain is driven by wind. Full site enclosure (tenting) represents the ideal scenario, but it is often costly and not always feasible due to space constraints or the size of the structure.

LOCALISED MEASURES • tape the joints • rout recesses for connections to promote drainage • cover the tops of wall panels to promote water run-off

$ low cost

SURFACE MEASURES • apply temporary top or side coverings (in the case of wind-driven rain) • apply membranes to entire panels

TOTAL MEASURES • fully enclose the construction site (tenting)

$$ high risk

medium cost

$$$ medium risk

high cost

low risk

COST RISK

construction period and weather window severity

The objective is not to prescribe a single solution, but to assess the risk and select protective measures consistent with the construction period, weather conditions and exposure of the elements. In many cases, the assessment process leads to different combinations of protective measures, which may vary throughout the construction period. The selection of protective measures according to the severity of the weather window is not related solely to corrosivity, but also to the potential impact of timber swelling, which in some cases can generate significant unforeseen loads. CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 23

T TE S

CORROSION ON SITE: TYPICAL SCENARIO Rothoblaas conducted a testing campaign to study the progression of fastener corrosion by varying: • exposure conditions (moisture), • wood species, • fastener materials and coatings. The samples were installed in timber and left under the specified exposure conditions for 12 months. For each configuration, 12 samples were prepared. One sample was removed at the end of each month, allowing the progression of the phenomenon to be assessed on a monthly basis. White corrosion affects the zinc-plated layer. It indicates that the coating is reacting with the environment and performing its sacrificial protection function for the steel. Although visually evident, it does not result in a significant loss of performance over the design life of the building.

Red corrosion, on the other hand, consists of the corrosion products of carbon steel. It indicates that, in that area, the zinc layer has been completely consumed and the steel is exposed. This phenomenon significantly affects the durability of the connection.

Fasteners showing red corrosion during construction must be removed and replaced.

Corrosion assessment was carried out using the first visible signs of corrosion (red or white), detectable with the naked eye, as the evaluation criterion. It is important to note that the times observed for the onset of corrosion phenomena depend on the climatic conditions during testing, particularly rainfall and the environmental corrosion class (C2 in this specific case). The values reported should therefore be considered indicative and applicable only to this specific test scenario.

S TE T

TYPICAL SCENARIO exposure conditions:

SC1

SC2

SC3

SC4 unprotected exposure

type of wood:

firT4

white corrosion

red corrosion

presence of whitish deposits, indicating the reaction of the coating with the environment and its sacrificial protection function for the steel.

presence of reddish deposits, indicating that the zinc layer in that area has been completely consumed and the steel is exposed

month

ELECTRO PLATED

EVO COATING

1 month

ELECTRO PLATED

3 months

EVO COATING

ELECTRO PLATED

11 months

EVO COATING

ELECTRO PLATED

EVO COATING

Tests carried out on electro-galvanised carbon steel fasteners embedded in spruce timber showed: • no signs of white corrosion for approximately 2 months; • no red corrosion for approximately 10 months. Fasteners with the EVO coating, on the other hand, demonstrated significantly greater durability, thereby providing an important additional safety margin on site. It is normal for a coating such as electro-galvanising, designed for service classes 1 and 2, to show signs of corrosion when fully exposed to weathering, because environmental conditions during construction may be more aggressive than those anticipated in service. These results highlight the importance of: • protecting the construction site or connections where weather forecasts indicate prolonged exposure to the elements; • selecting higher-performance materials or coatings when the construction period may exceed the expected durability of the coating.

CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 25

T TE S

CORROSION ON SITE: HIGH-AGGRESSIVENESS SCENARIOS In this series of tests, various coatings on carbon steel and stainless steel were analysed in combination with less common, yet still relevant, wood species. These included acidic timber, such as oak, which represents a particularly aggressive case and therefore serves as a useful reference for other acidic wood species. Thermally-modified timber and acetylated timber were also tested. As in the previous tests, the samples were exposed for 12 months, with one screw removed each month to assess the progression of corrosion over time.

ACID TIMBER exposure conditions: T1

type of wood:

SC1

SC2

SC3

SC4 unprotected exposure

T5 oak

white corrosion

red corrosion

presence of whitish deposits, indicating the reaction of the coating with the environment and its sacrificial protection function for the steel.

presence of reddish deposits, indicating that the zinc layer in that area has been completely consumed and the steel is exposed

month

ELECTRO PLATED

HOT DIP

410

AISI

EVO COATING

The results show that, under fully exposed design conditions (SC3 / Wet), coatings on carbon steel are generally unsuitable, whereas AISI 410 stainless steel showed no visible signs of corrosion throughout the entire test period. During construction, the progressive development of corrosion can be observed across the various coatings tested. The EVO coating proved to be a suitable solution for medium-length construction projects, offering superior performance compared with hot-dip galvanising. For further information on coating types, please refer to the TIMBER SCREWS SMARTBOOK.

26 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

S TE T

1 month

3 months

HOT DIP

ELECTRO PLATED

EVO COATING

HOT DIP

ELECTRO PLATED

1 month

11 months

3 months

410 AISI

EVO COATING

HOT DIP

ELECTRO PLATED

11 months

410 AISI

EVO COATING

410 AISI

CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 27

T TE S HEAT-TREATED WOOD

exposure conditions: T1

type of wood:

SC1

SC2

SC3

SC4 unprotected exposure (screws partially embedded in timber)

T5 thermally-modified tulipwood

white corrosion

red corrosion

presence of whitish deposits, indicating the reaction of the coating with the environment and its sacrificial protection function for the steel.

presence of reddish deposits, indicating that the zinc layer in that area has been completely consumed and the steel is exposed

month

ORGANIC COATING

410

ELECTRO PLATED

EVO COATING

AISI

1 month

ORGANIC COATING

410

ELECTRO PLATED

AISI

EVO COATING

3 months

ORGANIC COATING

ELECTRO PLATED

410

EVO COATING

AISI

11 months

ELECTRO PLATED

EVO COATING

11 months ORGANIC COATING

410 AISI

Thermally-modified timber exhibits higher corrosivity than untreated timber. In the case of electro-galvanised fasteners, red corrosion appeared as early as the third month. By contrast, EVO C4, organic coating and AISI 410 showed no signs of corrosion throughout the 12-month test period. 28 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

S TE T

ACETYLATED WOOD white corrosion

red corrosion

presence of whitish deposits, indicating the reaction of the coating with the environment and its sacrificial protection function for the steel.

presence of reddish deposits, indicating that the zinc layer in that area has been completely consumed and the steel is exposed

exposure conditions: T1

type of wood:

month

SC1

SC2

SC3

SC4 unprotected exposure

T5 acetylated timber (Accoya)

ELECTRO PLATED

1 month

3 months

exposure conditions: T1

type of wood: month

ELECTRO PLATED

1 month

11 months

SC1

SC2

SC3

SC4 protected exposure

T5 acetylated timber (Accoya)

3 months

11 months

Acetylated timber is classified in corrosivity class T4 and, under service conditions, requires the use of stainless steel. The test was useful in highlighting the difference between: • fully exposed conditions (SC3) • protected conditions (SC3 non-exposed), introduced in the new Eurocode 5 The difference is significant: under fully exposed conditions, red corrosion appears as early as the third month, whereas under protected conditions it may not occur for up to 12 months.

CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 29

T TE S

CORROSION ON SITE: GALVANIC COUPLING Galvanic coupling occurs when dissimilar metals are brought into contact in the presence of moisture. Under these conditions, the potential difference generates a galvanic current that can cause localised corrosion. In indoor (dry) environments, this phenomenon is rarely critical, whereas on construction sites and under weather exposure it can become a significant factor affecting the durability of the structure. To measure and quantify this effect, Rothoblaas carried out a testing campaign in collaboration with the University of Trento, using a potentiostat in ZRA (Zero Resistance Ammeter) mode in accordance with ASTM G71. The tests covered various combinations of screws, washers, post bases and LOCK connectors, coupled with different materials and coatings.

GALVANIC COUPLING TEST galvanic current vs potential difference for macroscopic galvanic couples. MATERIALS TESTED electro-galvanised coating with chromium passivation Fe/Zn hot dip galvanising coated carbon steel EVO C4 coating DAC COAT organic coating EN AW-6082 aluminium alloy aluminium

EN AW-6005A aluminium alloy EN AW-6005A aluminium alloy + EVO coating martensitic stainless steel AISI 410

stainless steel

austenitic stainless steel A2 / AISI 304 austenitic stainless steel A4 / AISI 316 HCR A8 / AL-6XN super-austenitic stainless steel

In the graph: • the horizontal axis represents the potential difference between the two metals and indicates both how electrochemically different they are and which of the two tends to corrode; • the vertical axis represents the intensity of the galvanic current. Higher values correspond to greater corrosion. Each coloured rectangle represents the set of results obtained for a specific material pairing. The greater its development along the vertical axis, the greater the dimensional effect observed during testing, determined by testing the same materials using components of different sizes, ranging from washers approximately 30 mm in diameter to post bases with an area of approximately 200 cm2 .

For further information, the complete test report is available at www.rothoblaas.com

30 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

S TE T

600 SIGNIFICANT CORROSION

higher corrosion rate

galvanic current [μA]

400

200

B C 100

lower corrosion rate

significant corrosion limit

D E F

COMPATIBILITY ZONE

0 -1,0

0,0

-0,5

0,5

the plate corrodes

1,0

the screw corrodes potential difference ΔE [V]

COUPLINGS Zn / EVO screw + stainless steel plate

Zn / EVO screw + HDG plate

the screw corrodes ΔE ≈ +0,9 V · 129–513 µA stainless steel screw + Zn / EVO /HDG / Dac-coat plate the plate corrodes ΔE ≈0,4−0,9 V · 61–447 µA

Zn / EVO screw + Al plate

negligible corrosion on Zn

ΔE ≈ −0,3 V · 10-50 µA other pairings of similar materials

stainless steel screw + Al plate (LOCK)

compatibility close to limit

ΔE ≈ −0,03 V · 10-60 µA

the aluminium corrodes ΔE ≈ −0,6 V · 110–122 µA

EVO–Zn, INOX–INOX, EVO/Zn-Dac-coat

ΔE ≈ 0 V · I < 50 µA

Rectangle height: cathode size variability (washer Ø ~30 mm Method: Potentiostatic ZRA — ASTM G71

plate ~200 cm2).

KEY FINDINGS Galvanic current measurements (ZRA) show: • a significant potential difference between zinc-based coatings (electro-galvanising, EVO) and stainless steels; • a significant potential difference also between uncoated aluminium (LOCK) and stainless steels (AISI 410). Conversely, the measurements indicate: • an almost negligible potential difference between different zinc-based coatings (for example EVO vs electro-galvanising); • an almost negligible potential difference between different stainless steels (for example AISI 410 and AISI 316); • in pairings between zinc-based coatings (electro-galvanising or EVO) and aluminium, or between electro-galvanising and hot-dip galvanising, the corrosion phenomena observed are not such as to compromise the coupling, which can generally be considered acceptable. CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 31

PRACTICAL COMPATIBILITY TABLE LEGEND possible coupling coupling with limited corrosion coupling not possible The anodic element (zinc) undergoes significant corrosion.

washer/plate

ELECTRO PLATED

EVO COATING

HOT DIP

DAC COAT

alu

alu EVO

AISI 304

AISI 316

ELECTRO PLATED

screw

EVO COATING

410

(*)

AISI

AISI 304

AISI 316

NOTE: The indications provided in the table are valid provided that the exposure conditions specified for each material/coating are respected. For further information, see the TIMBER SCREWS SMARTBOOK. (*) see the section below entitled “TIMBER AND GALVANIC COUPLING”.

TIMBER AND GALVANIC COUPLING Where connections are located outdoors but installed within protected and sealed joints, preventing the ingress of free water or exposure to weathering agents, the surrounding timber may also provide a protective effect against galvanic corrosion. Under these conditions, it is sufficient for the paired materials to be compatible with both the corrosivity of the timber and that of the exposure environment. In such situations, the use of pairings that are normally discouraged (e.g. aluminium with stainless steel) may be considered following a technical assessment supported by Rothoblaas.

32 | CORROSIVITY CONDITIONS ON SITE | CONNECTIONS

CORROSION ON SITE: HYDROGEN EMBRITTLEMENT Under certain conditions, corrosion may be associated with a more complex phenomenon known as hydrogen embrittlement, which can lead to the initiation and propagation of microcracks in the steel, ultimately resulting in brittle failure of the fastener under load.

For the phenomenon to occur, several conditions generally need to be simultaneously satisfied:

Presence of moisture, which activates the corrosive environment within the timber and may promote galvanic coupling between dissimilar materials.

Damage to, or discontinuities in, the coating that may occur during installation.

Stresses within the fastener, resulting from applied loads or, more commonly, from suboptimal installation conditions.

Prevention of this phenomenon requires a combination of several protective measures. The most important include:

EVO COATING

Correct installation, reducing the risk of coating damage and the introduction of undesirable stresses into the fastener.

Selection of materials or coatings appropriate to the corrosion expected under both service and construction conditions.

Protection from moisture through proper site management and temporary protection of connections from water ingress.

For further information on premature failure and the role of hydrogen embrittlement in timber fasteners, please refer to the White Paper “Premature Failure in Timber Screws: Insights into Hydrogen Embrittlement and Stress-Driven Risk”.

CONNECTIONS | CORROSIVITY CONDITIONS ON SITE | 33

CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT

RISK ON SITE Potential risks whose effects may manifest directly on site, compromising the stability of the structure and the safety of those working within it. LONG-TERM DESIGN RISK Potential risks resulting from inadequate design, discussed in detail throughout the various chapters of this Smartbook. If not properly managed or mitigated, these issues may affect the long-term durability of the structure. 34 | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | CONNECTIONS

CONNECTIONS | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | 35

1. TIMBER-TO-STEEL CONNECTIONS IN AREAS PRONE TO STANDING WATER LOW RISK Connection with a thick steel plate, potentially sensitive to screw installation errors. However, this condition is characterised by a low risk of exposure to weathering and the absence of standing water. MEDIUM RISK Connection with a steel plate potentially exposed to water on site. The vertical configuration promotes drainage but does not eliminate the possibility of standing water at the wall-to-beam interface. HIGH RISK Connection with a thick steel plate in an area subject to standing water and pooling.

RISK OF WATER INGRESS ON SITE

During construction, rainfall may cause water ingress at the exposed tops of CLT panels.

Where water accumulates, the timber rapidly absorbs moisture, resulting in timber swelling and corrosion of metal components.

The use of acoustic isolation mats beneath the wall separates the timber from the water and prevents excessive moisture absorption. Extend the protection 300 mm above floor level and cover the metal components and joints.

36 | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | CONNECTIONS

2. STANDING WATER AND POOLING ON SITE

High-risk connection: thick steel plate in an area subject to standing water and pooling.

Temporary site protection sealing the most sensitive areas.

During construction, temporary protective membranes are often subjected to significant stresses, such as panels being dragged or accidental trampling of nails or screws. Although membranes are designed to withstand site operating conditions, they may nevertheless become damaged over time. Once the floor surface has been waterproofed, provision should be made for water drainage, preferably directing water outside and away from the timber structures.

CONNECTIONS | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | 37

3. TIMBER–TO–STEEL CONNECTIONS AT THE BUILDING PERIMETER LOW RISK If the connection is localised, water can drain away quickly. If the connection is continuous, as in the case of LOCK FLOOR, drainage points must be provided by separating the profiles. HIGH RISK Connection with a thick steel plate located in an area prone to standing water and pooling. Façade plates, positioned along the building perimeter, are among the elements most exposed to water during construction.

Install a membrane between the plate and the timber. Rothoblaas recommends DEFENCE ADHESIVE.

Cover the plate with a waterproof element. The connection is located on the building perimeter and requires careful protection.

Ventilation cavities can create a chimney effect and, in the event of a fire, accelerate the spread of flames. For this reason, the use of products with a fire reaction class higher than the standard is recommended, particularly products classified as B-s1, d0 (EN 13501) or higher.

See further details under “ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS” on page 72

38 | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | CONNECTIONS

4. TIMBER–TO–STEEL CONNECTIONS AT THE BUILDING PERIMETER MEDIUM RISK A vertical localised connection is less susceptible to standing water, allowing water to drain quickly and the timber to dry. However, the thick steel plate remains an area more exposed to water and requires appropriate protective measures.

Install a membrane between the plate and the timber.

Seal the upper joint with tape to prevent water ingress.

ROTHOBLAAS RECOMMENDS DEFENCE ADHESIVE

INVISI BAND

SELF-ADHESIVE PROTECTIVE MEMBRANE FOR BUILDING ELEMENTS

TRANSPARENT SINGLE-SIDED ADHESIVE TAPE WITHOUT LINER, RESISTANT TO UV AND HIGH TEMPERATURES

CONNECTIONS | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | 39

5. RISKS ASSOCIATED WITH BALCONIES IN TIMBER STRUCTURES The balcony junction is a critical detail that must ensure both stability and durability over time.

When the CLT panel is continuous with the balcony, no structural connections are present at floor level. This configuration reduces the risks associated with complex connection details but increases vulnerability to water ingress. In the event of ingress, water can spread from the exterior to the interior of the building, facilitated by the structural continuity between the two areas. Any deterioration or decay may therefore compromise not only the balcony but also the internal floor structure. For this reason, the timber element must be designed and built with a level of waterproofing equivalent to that required for flat roofs and terraces.

Where the balcony is not continuous with the CLT floor structure, careful consideration must be given to the material and construction solution adopted for the cantilevered balcony. Integrating the projecting balcony by means of a joint or connection requires the use of metal structural elements, often characterised by their high thickness. These elements constitute potentially weak points: located on the external perimeter of the building, they are exposed to water. Specific protection and treatment measures must be provided to ensure the durability of the system.

ROTHOBLAAS RECOMMENDS BYTUM BASE 2500 SELF-ADHESIVE BITUMINOUS MEMBRANE

See further details under “RAINWATER DRAINAGE AND DEFLECTION” on page 156

40 | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | CONNECTIONS

Exposure of timber to moisture significantly reduces its long-term durability. For external elements such as balconies, it is advisable to adopt construction systems and connections that allow easy dismantling in the event of water ingress. It is recommended to use replaceable external structures that can be removed without intervening on the building's primary structure. One example is external landings supported by independent columns, allowing the balcony to be removed without affecting the internal floor structure or other structural elements. Various solutions are available for fastening easily demountable external structures. Among these, side railings can be used as structural elements, acting as cantilever beams fixed to the façade by means of certified angle brackets capable of resisting shear and tensile forces. This represents an alternative, yet compliant and certified use of our ANGLE BRACKETS or HOLD DOWN systems, enabling the construction of efficient, reversible structures that meet durability and maintainability requirements.

SLOPE 1°

Example: TITAN S angle bracket with high tensile strength. The combination of a thin plate and a large-diameter screw reduces the forces generated by timber swelling. Easily demountable solution.

The separation between the balcony structure and the building structure allows a layer of thermal insulation to be installed, reducing thermal bridging. This separation also improves durability: in the event of water ingress, water cannot reach the internal structure, limiting damage to load-bearing elements.

CONNECTIONS | CRITICAL CONNECTIONS: IDENTIFICATION AND ASSESSMENT | 41

CONNECTION DETAILS FOR MANAGING WATER AND MOISTURE

The durability principles discussed in the chapter “BASE CONNECTIONS: JUNCTION DESIGN” (p. 130) also apply to connection details. Risk management is based on four key aspects: • surface protection of the elements • protection and sealing of the joint • proper management of water drainage (avoiding standing water) • adequate ventilation

RISK ASSESSMENT

LEVEL OF PROTECTION

EFFECT

very low risk

complete protection, with all holes and joints sealed and drainage provided at weak points

elements fully protected against water ingress and standing water

low risk

elements protected over most of their surface, with drainage provided at weak points

elements protected only near weak points, with a limited risk of water ingress

medium risk

partial protection of timber elements, with exposed connectors and no drainage management at weak points

elements partially protected, with possible water ingress

no protection

unprotected elements

high risk

The level of risk also depends on factors such as the construction period, geographical location, proximity to aggressive environments, and the moisture content of timber elements, particularly where seasoning processes are involved. The acceptability of the risk is the responsibility of the designer.

See further details under “CORROSIVITY CONDITIONS ON SITE” on page 18

42 | CONNECTION DETAILS FOR MANAGING WATER AND MOISTURE | CONNECTIONS

INTERNAL KNIFE-PLATE JOINT Although the routed profile promotes water drainage and the head protection limits moisture uptake at the most critical location, the connection remains partially exposed, creating a risk of corrosion of the metal components. It is common practice to protect the timber beam with a membrane; however, following assembly of the beam and connection, openings will remain in the membrane: on the top of the beam and where the dowels are installed.

Full sealing, applying tape to the area adjacent to the routing, prevents moisture absorption by the timber, improving the durability of the connection. In addition, applying a protective membrane to the beam limits water absorption during the transport and storage of timber structural elements.

CONNECTIONS | CONNECTION DETAILS FOR MANAGING WATER AND MOISTURE | 43

IPE BEAM-CLT ELEMENT CONNECTION The use of tapes and/or membranes significantly reduces water absorption. Joints should provide adequate overlap, avoiding localised stresses on the membrane.

It is important to facilitate water drainage from weak points to prevent standing water in the event of localised water ingress. For example, slopes and packing may be introduced to create drainage paths, which also function as ventilation zones for drying.

anti-tear wedge

timber or insulating wedge drainage and ventilation

44 | CONNECTION DETAILS FOR MANAGING WATER AND MOISTURE | CONNECTIONS

LINEAR JOINTS

Standing water must be avoided, particularly in geometries that promote water pooling. Exposure of the connection causes corrosion of the metal connectors and swelling of the timber, reducing the durability of the joint.

The use of membranes alone limits water ingress through capillary absorption, reduces the risk of localised swelling and improves the durability of timber elements. However, the possibility of standing water remains, as does the risk of localised membrane punctures that may compromise its effectiveness.

≥ 30 mm

The use of membranes and/or tapes to seal joints significantly reduces water ingress into the gaps between connected panels. However, issues remain relating to the exposure, even if partial, of the elements and the risk of localised puncturing of the membranes. Local protection of the connection area limits the risk of corrosion and the effects of localised swelling, but does not eliminate timber durability issues or the effects of non-uniform swelling on a larger scale.

≥ 30 mm

Membranes and tapes, applied to timber elements and connections, provide a high level of protection for the joint. Protection must be continuous and properly integrated at connection points, with particular attention to standing water and localised puncturing caused by connectors.

CONNECTIONS | CONNECTION DETAILS FOR MANAGING WATER AND MOISTURE | 45

INSTALLATION AND INSPECTION OF FASTENING SYSTEMS CORRECT INSTALLATION TORQUE During installation, the torque setting must be sufficient to overcome the resistance to insertion and allow the screw to penetrate the timber. Installation should be stopped as soon as the head comes into contact with the metal element or is fully embedded in the timber. Further tightening does not improve the safety of the connection. Instead, it increases the risk of damage or failure.

Mins,rec

CORRECT INSERTION ANGLE The connector performs correctly only if the specified installation angle is respected. This check is particularly important in connections involving metal plates.

UNIFORM STRESS DISTRIBUTION To prevent certain screws from being subjected to higher loads than others and to ensure the proper "group effect" assumed by calculation models, screws must be tightened with torque values that are as uniform as possible and following an appropriate installation sequence.

αrec

Mins

S TE T

TIGHTENING RECOMMENDED INSERTION MOMENT The torque required to install a screw depends on the type and dimensions of the connector, as well as the characteristics of the substrate. To ensure correct installation, the applied torque must be suited to the actual application conditions and controlled using appropriate equipment. Even under identical installation conditions, the torque required for insertion may vary. For this reason, reference should be made to an installation torque range within which effective screw installation is ensured without compromising the performance of the connection. The recommended insertion torque shall be determined according to the actual insertion length (L ins).

Insertion torque trends for different screws and insertion lengths: 1,2 δL max = 1,00

δL max = 1,00

1,0

Mins / Mins,max [%]

δL min = 1,00

0,8 δL max = 0,66 δL min = 0,66

0,6

0,4

δL max = 0,33 δL min = 0,33

δL min = 0,33

0,2

0 0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Lins / Lmax,ETA [%] δL max

fully threaded screw with L ins / L max,ETA = 40%

δL min

fully threaded screw with L ins / L max,ETA = 70% fully threaded screw with L ins / L max,ETA = 100% partially thread screw

Lins / Lmax,ETA

< 17%

17% - 33%

33% - 66%

> 66%

δL min δL max

0,33

0,66

1,00

0,33

0,66

1,00

This distinction is particularly important for fully threaded screws; for partially threaded screws, δL = 1.00 is always assumed. CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 47

RECOMMENDED INSTALLATION TORQUE (Mins, rec) As a manufacturer of high-performance fasteners, Rothoblaas specifies, for each screw type, diameter and insertion length, a recommended installation torque range (M ins,rec,min and Mins,rec,max). It is recommended that screw insertion be stopped as soon as the head comes into contact with the metal plate in steel-to-timber connections, or when the upper surface of the head is flush with the surface of the timber element (unless specific geometric requirements apply, such as recessing the head into the timber). CARBON STEEL SCREWS (electro-galvanised and EVO-coated) d

[mm]

[Nm]

≤ 100

> 100

≤ 120

> 120

≤ 140

> 140

HBS PLATE

10 12

VGS PLATE LBS HARDWOOD (*)

11 5 7

VGS VGZ

VGZ HARDWOOD (*)

6 8

Mins,rec,min Mins,rec,max

≤ 160

> 160

≤ 120

≤ 100

> 100

< 160

160 - 280

[in]

[ft-lbs]

≤ 4''

> 4''

0.32 0.40 0.48 0.44 0.20 0.28

0.28

Mins,rec,min Mins,rec,max [ft-lbs]

≤ 4 3/4''

> 4 3/4''

≤ 5 1/2''

> 5 1/2''

≤ 6 1/4''

> 6 1/4''

≤ 4 3/4''

≤ 4''

> 4''

< 6 1/4''

6 1/4'' - 11''

8 8

> 280

> 11''

< 200

< 8''

200 - 360

8'' - 14 1/4''

14 14

0.36

> 360

> 14 1/4''

≤ 350

≤ 13 3/4''

350 - 600

> 600

> 23 5/8''

< 250

< 10''

250 - 500

10'' - 19 3/4''

500 - 1000

> 1000

≤ 220

> 220

≤ 280

> 280

0.44 13 3/4'' - 23 5/8''

0.52

0.24 0.32

19 3/4'' - 39 3/8''

> 39 3/8''

≤ 8 5/8''

> 8 5/8''

≤ 11''

> 11''

14 2

≤ 70

0.20

≤ 2 3/4''

≤ 100

0.28

≤ 4''

≤ 120

0.20

≤ 4 3/4''

HBS

≤ 400

0.24

≤ 15 3/4''

TBS

≤ 600

0.32

≤ 23 5/8''

HBSP

≤ 600

0.40

≤ 23 5/8''

≤ 1000

0.48

≤ 39 3/8''

≤ 160

0.24

≤ 6 1/4''

≤ 480

0.32

≤ 19''

LBS

HBS HARDWOOD (*)

48 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

STAINLESS STEEL SCREWS d

[mm]

[Nm]

≤ 100

> 100

HBS PLATE A4

10 12 9

VGS A4

≤ 120

> 120

≤ 140

> 140

≤ 240

> 240

< 250

250 - 400

≤ 100

≤ 160

≤ 320

SCI A2

Mins,rec,min Mins,rec,max

[in]

[ft-lbs]

≤ 4''

> 4''

≤ 4 3/4''

> 4 3/4''

0.32 0.40 0.48 0.36

Mins,rec,min Mins,rec,max [ft-lbs]

≤ 5 1/2''

> 5 1/2''

≤ 9 1/2''

> 9 1/2''

< 10''

10'' - 19 3/4''

0.20

≤ 4''

0.24

≤ 6 1/4''

0.32

≤ 12 5/8''

0.44

The tabulated values apply to the insertion of screws in spruce timber (maximum density 490 kg/m3 / SG < 0.47) without pre-drilling. They are derived from experimental testing based on ETA-11/0030 and in compliance with the torsional resistance of the connector. ( *) For installation in hardwood, the tabulated values may be increased by 25%.

To avoid overtorque, the minimum installation torque (Mins,rec,min) must be applied. If the screw cannot be inserted, the torque may be increased up to the maximum recommended torque value (Mins,rec,max).

When installing through a metal plate, the use of a TORQUE LIMITER is recommended; in this configuration, Mins,rec,max may be set.

TIGHTENING CONTROL Control of the installation torque must be ensured through the use of suitable tools capable of monitoring and limiting the torque applied during installation.

ROTHOBLAAS RECOMMENDS TORQUE LIMITER

BEAR

TORQUE LIMITER

TORQUE WRENCH

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 49

T TE S OVERTORQUE: EFFECTS ON THE CONNECTOR To penetrate the timber, a screw must be installed with sufficient insertion torque to overcome the material's resistance to screw insertion. When the screw head comes into contact with the plate, the plate acts as a restraint, preventing further penetration of the screw into the timber. If tightening torque continues to be applied, a secondary tensile load is generated in the screw: the screw tends to advance, but its movement is restrained by the metal element. The tensile load induced in the screw is directly proportional to the overtorque applied.

Secondary tensile force as a function of the overtorque

secondary tensile force in screw: Fpre-tens [kN]

20 15 10

5 0 0

overtorque Mins - Mins,rec,max [Nm] experimental data trend

To analyse and quantify the risk associated with this phenomenon, Rothoblaas conducted dedicated experimental tests using load cells and driving screws through thick steel plates, progressively increasing the installation torque to generate overtorque. Effects of overtorque 20000

screw:

18000

VGS Ø9 x 200 mm

16000

F [N]

14000

Mins = 60 Nm

12000 10000 8000 6000

Mins = 40 Nm

4000 2000

Mins = 20 Nm

0 0

Mins

time [h] insertion at 60 Nm insertion at 40 Nm insertion at 20 Nm = Mins,rec,max A. Notari (2026) - Designing the Durability of Timber Joints: Hygroscopic Effects and Site Application

50 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

S TE T

OVERTORQUE: EFFECTS ON THE TIMBER If excessive installation torque is applied during installation (Mins > Mins,rec), an over-tightening condition occurs. Once the screw head comes into contact with the plate, further penetration into the timber is prevented. Excessive tightening can cause thread stripping, resulting in damage to the timber grain and a reduction in pull-out strength. In the case of correct installation without overtorque (OT), the phenomenon is generally limited, particularly when thin plates are used, as they are less stiff, more deformable and offer less resistance to screw advancement. In the presence of OT and thick plates, once the screw head comes into contact with the plate, the thread encounters greater resistance to advancement and tends to damage the surrounding timber grain, increasing thread stripping. The most critical condition occurs when impact drivers are used without torque control, as this further amplifies damage to the timber.

thin plate

thick plate

OVER-TORQUING OT

100%

pull-out strength

75% (-25%) pull-out strength

25% (-75%) pull-out strength

For short screws, experimental testing (Alma Mater Studiorum – University of Bologna, Research Centre for Building and Construction) shows that tightening beyond the recommended value significantly reduces pull-out strength: the screw strips the timber, degrading the performance of the anchor system. SOURCE: Bellini, A.; Morganti, A.; Conquista, F.; Savoia, M.; Pozza, L. (2025). Reuse of HBS PLATE screws on RAPTOR lifting hook: Definition of representative damage mechanism of screw during use and experimental characterization of RAPTOR lifting hook fastened with damaged screws. Alma Mater Studiorum – Università di Bologna, CIRI Edilizia e Costruzioni.

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 51

T TE S INSTALLATION INSPECTION Tightening is inspected using the reverse procedure, employing a torque wrench to measure the loosening torque of a screw installed through a metal plate; this value is correlated with the degree of tightening applied during installation. During inspection, it must be verified that the ratio between the loosening torque (Mloos, insp) and the recommended tightening torque falls within the limits specified in the table below.

Mloos,insp / Mins,rec,max

< 0,35

0,35 < x < 0,45

> 0,45

low risk

medium risk

high risk

correct tightening torque

limit tightening torque

excessive tightening torque (OT)

2,6 2,4 2,2 2,0

Mins / Mins,rec,max

1,8 1,6 1,4 1,2 1,0 0,8 0,6 0,4 0,2 0 0,25

0,30

0,35

0,32

0,40

0,45

0,50

0,55

0,60

0,65

0,70

0,75

0,55 Mloos,insp / Mins,rec,max

The graph shows the installation examples presented on the following page.

The graph derived from the test results provides a qualitative assessment of the applied torque based on the loosening torque. The curves represent the minimum and maximum torque values applied during installation.

Mloos,insp

EXAMPLE how to carry out a correct installation and check by inspection screw:

HBSPL Ø10 x 180 mm

support:

spruce glulam (without pre-drilling)

INSTALLATION the recommended installation torque from the table 1 Determine according to the screw type, diameter and insertion length;

Mins,rec,min = 15 Nm Mins,rec,max = 30 Nm

the connector with the torque control 2 Insert set to Mins,rec,min.

Mins = Mins,rec,min = 15 Nm

If the screw cannot be inserted, the tightening torque

3 may be increased up to Mins,rec,max.

Mins = Mins,rec,max = 30 Nm

4 Ensure that the recommended installation torque is not exceeded during insertion. Mins = 20 Nm

installation torque:

Mins = 40 Nm

installation torque:

INSPECTION

1 Record the loosening torque

Mloos,insp

it with the maximum recommended 2 Compare installation torque

Mloos,insp = 9,5 Nm

loosening torque: CONTROL PARAMETER

loosening torque:

Mloos,insp = 16,5 Nm

CONTROL PARAMETER

Mloos,insp / Mins,rec,max = 9,5 Nm/30 Nm =

0,32

Mloos,insp / Mins,rec,min

low risk

Mloos,insp / Mins,rec,max = 16,5 Nm/30 Nm =

0,55

high risk

It is assumed that the installation torque applied is between 0.55 and 0.75 times the maximum recommended torque.

It is assumed that the installation torque applied is between 1.45 and 1.90 times the maximum recommended torque.

correct installation

over-torquing (OT)

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 53

UNIFORM STRESS DISTRIBUTION A consistent installation sequence must be defined to ensure correct and uniform load distribution among all connectors. For axially loaded screws, the use of positioning screws is always recommended in order to prevent sudden or unintended displacement of the elements being connected, particularly where metal plates are involved. As a general rule, asymmetric or random installation sequences should be avoided. Instead, screws should be installed following an orderly sequence, for example progressing from one side of the joint to the other or adopting a cross-pattern arrangement, both for positioning screws and structural screws. This approach enables a more uniform distribution of stresses and a more balanced overall structural response of the connection.

ALUMEGA JVG

tightening option 1

tightening option 2

The full assembly instructions are available at www.rothoblaas.com

54 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

How to correctly install a screw The full installation instructions for timber screws are available at rothoblaas.com.

rothoblaas.com

INSERTION ANGLE According to Eurocode 5 – Part 3 Execution: Fpr EN 1995:2025-3, during installation, a maximum deviation (Δα) of 5° is permitted between the actual installation angle (α install) and the design angle (α rec), with no variation in the strength or stiffness of the connection:

correct insertion angle

limit insertion angle

excessive insertion angle

low risk

medium risk

high risk

Δα < ± 3°

Δα ≤ ± 5°

Δα > ± 5°

αinstall -5° -3° -20°

free installation

+3° +5° +20°

installation with jig

Depending on the installation method, deviations from the recommended angle may be greater or smaller.

Δα = αinstall - αrec αrec

SENSITIVITY TO DEVIATION WITH RESPECT TO THE SCREW HEAD GEOMETRY Depending on the installation method and the material in contact with the screw head, deviation from the recommended insertion angle may be more or less critical. The deviation is more marked when the screw head bears against a stiff, low-deformability material, such as a metal plate. Under these conditions, any angular misalignment cannot be absorbed by deformation of the supporting material and results in non-uniform distribution of contact stresses. By contrast, when the screw head bears against timber, the greater deformability of the material allows partial adaptation of the bearing area, reducing the adverse effects of minor misalignments.

SENSITIVITY AS A FUNCTION OF THE DEFORMABILITY OF THE MATERIAL IN CONTACT WITH THE HEAD

dUK

thick steel plate

thick aluminium plate

thin metal plate

dK /dUK

beech LVL

hard woods

softwood

Head geometry ratio The sensitivity of the screw head to secondary bending moments caused by angular deviation depends on the ratio between the head diameter (dK) and the under-head diameter (dUK).

Plate-fastening head (HBS PLATE, LBS, VGS PLATE)

Countersunk head for use in countersunk holes (HBS, VGS)

Hexagonal head (KOP, KOS)

Flange head (TBS, TBS MAX) the use of flange-head screws in metal-totimber connections is strongly discouraged.

Cylindrical head (VGZ, DGZ)

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 57

INSTALLATION WITH JIGS STARTER HOLE: PRE-DRILLING AND PILOT HOLE Pre-drilling allows the screw to be inserted with less effort and minimises damage to the timber, whereas pilot or guide holes are used primarily to ensure correct screw alignment.

INSTALLATION AT 90°

INSTALLATION AT 45°

90° cylindrical holes

45° pre-shaped holes

correct guidance of the screw tip and correct insertion direction

pre-drilled or pilot hole with correct inclination and diameter

E.g. ALUMEGA, perforated IPE profiles

E.g. ALUMEGA

JIG VGS

JIGVGS9

JIGVGSH9

JIGVGS9

JIGVGSH9

dv = 5 mm

dv = 6 mm

dv = 5 mm

dv = 6 mm

HBS PLATE Ø8

HBS PLATE Ø10

VGS Ø9

VGSH Ø9

58 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

INSTALLATION AT 45° VGU (pre-positioned)

VGU (plates with slotted holes)

pre-drilled or pilot hole with correct inclination and diameter

E.g. SPIDER (with welded VGU)

E.g. VGU PLATE T

JIG VGU

JIG VGU TOTAL

JIGVGU945

JIGVGU1145

JIGVGU1345

JIGVGU945T

JIGVGU1145T

JIGVGU1345T

dv = 5 mm

dv = 6 mm

dv = 8 mm

dv = 5 mm

dv = 6 mm

dv = 8 mm

VGS Ø9

VGS Ø11

VGS Ø13

VGS Ø9

VGS Ø11

VGS Ø13

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 59

USE OF SACRIFICIAL JIGS ENSURING THE INSTALLATION ANGLE ROTHOBLAAS RECOMMENDS FIT JIG HP

FIT JIG VG

SACRIFICIAL JIG FOR HBS PLATE SCREWS

SACRIFICIAL JIG FOR VGS SCREWS

FIT JIG HP and FIT JIG VG sacrificial jigs represent a significant advancement in screw application. They enable precise insertion angles even without the aid of a pilot hole in standard applications. They do not replace the full pre-drilling required to ensure correct installation when using long screws, where exceptionally high accuracy is required, or when working with high-density timber elements.

SIGNIFICANT REDUCTION IN INSTALLATION STRESS More than just alignment. Manufactured from a deformable polymer material, it acts as a damper, absorbing up to 30% of the peak insertion moment generated by head-to-metal contact, thereby reducing damage, overtorque, overloads and stress concentrations. In addition, by preventing direct contact between the screw and the washer, it acts as an insulating element against galvanic corrosion.

60 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

INSTALLATION OF HBS PLATE SCREWS AT 90°

Insert the jig onto the screw until the tip protrudes.

Position the screw with the jig in the hole.

Continue driving the screw until it comes into contact with the plate.

If necessary, remove any remaining jig material around the screw and dispose of it.

INSTALLATION OF VGS SCREWS AT 45° WITH VGU

Insert the jig into the screw installation hole.

Insert the screw into the jig until the tip protrudes.

Continue driving the screw until it is flush with the outer surface of the FIT JIG.

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 61

INCORRECT INSERTION DIRECTION: SCREW FAILURE Any screw may fail during installation if it is driven at an angle that generates a secondary bending moment. This induces a combined shear and tensile stress in the head region, which may exceed the screw's strength even in the absence of moisture or corrosive phenomena. The image opposite illustrates the effect of installing HBSP screws through a thin steel plate into softwood at varying insertion angles (45°, 50° and 60°), combined with overtorque (OT). The correct reference angle is 90°.

Image source: Denz, C., Bestimmung möglicher Einflüsse auf die Tragfähigkeit von Stahlblech-Holz-Verbindungen mit Vollgewindeschrauben durch unsachgemäße Montage, Bachelor's thesis, KIT, 2023.

INCORRECT INSERTION DIRECTION: INDUCED ADDITIONAL STRESSES

Uniform, well-distributed contact surface.

Localised (as opposed to distributed) contact points, concentrated at the edges. Possible secondary bending moments.

INCORRECT INSERTION DIRECTION: DAMAGE In addition to immediate failure during installation, an incorrect insertion angle may lead to further issues.

Damage to the coating: reduced corrosion resistance and an increased risk of HI-SCC/EHE.

Damage to, or wear of the thread: reduced pull-out strength.

Plastic bending deformation: reduced tensile and bending resistance of the screw. Formation of microcracks.

See further details under “CORROSIVITY CONDITIONS ON SITE” on page 18

62 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

INSPECTION: INSERTION ANGLE It is recommended that a minimum representative number of screws be partially unscrewed for each connection type and that the insertion angle be measured using a protractor. It is important to check that the extracted screw shows no obvious signs of plastic deformation associated with over-tightened installation. correct insertion angle

limit insertion angle

excessive insertion angle

low risk

medium risk

high risk

Δα < ± 3°

αrec= 45° αinsp = 45,95° Δα = 0,95°

Δα ≤ ± 5°

Δα > ± 5°

αrec = 90° αinsp = 79,45° Δα = 10,55°

Δα = αinsp - αrec αrec

INSTALLATION WITH OVERTORQUE Compliance with the specified installation torque is essential for reliable verification of the insertion angle during inspection and to ensure the fastener has been safely installed. In the event of overtorque (OT), once the head bears against the surface, the screw tends to conform to the geometry of the hole, inducing bending and deformation along the shank and making angular installation errors far less evident during inspection. The test campaign carried out in collaboration with KIT (Karlsruhe Institute of Technology) demonstrated that tightening has a significant influence on the ability to detect an incorrect insertion angle during installation.

INSTALLATION AT 90° IF TORQUE CONTROL HAS BEEN USED: THE DEVIATION REMAINS VISIBLE AND IS NOT CORRECTED DURING TIGHTENING.

5°

10°

15°

Compliant installation: the head angle and position are correct and stable.

The deviation from the recommended angle remains visible and is not corrected during tightening.

Non-compliant installation: the excessive angle is easily identified during inspection.

Plate-fastening head HBS PLATE

IF TORQUE CONTROL HAS NOT BEEN USED: OVER-TIGHTENING MAY CONCEAL DEVIATIONS FROM THE RECOMMENDED INSERTION ANGLE Plate-fastening head HBS PLATE

5°

10°

15°

Even with the correct angle, the absence of torque control may cause deformation of the connector.

Over-tightening can mask deviations from the recommended installation angle.

Non-compliant installation: over-tightening may compensate for an incorrect inclination, inducing local deformations and stress concentrations.

64 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

INSTALLATION AT 45°

< 40°

45°

> 50°

IF TORQUE CONTROL HAS BEEN USED: THE DEVIATION REMAINS VISIBLE AND IS NOT CORRECTED DURING TIGHTENING.

< 40°

45°

Visible incorrect installation angle: possible lifting of the washer or screw head not fully in contact with the surface.

Compliant installation: the head angle and position are correct and stable.

> 50° Screw head not fully in contact with the surface (on the lower side).

IF TORQUE CONTROL HAS NOT BEEN USED: OVER-TIGHTENING MAY CONCEAL DEVIATIONS FROM THE RECOMMENDED INSERTION ANGLE

> 50°

< 40°

45°

Some lifting of the washer may be visible, but the actual angle cannot be clearly determined.

Even with the correct angle, the absence of torque control may induce local deformations and stress concentrations.

The actual angle cannot be determined visually: over-tightening may conceal an incorrect inclination.

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 65

INSPECTION: BROKEN SCREWS As discussed in the previous sections, a number of factors may lead to premature failure of fasteners. The graph provides an indicative representation of the time period in which the most common types of failure occur, from installation (time t = 0) until the completion of construction, when the connection is no longer exposed to weather conditions.

first rainfall

weather resistance

hydrogen stress corrosion cracking / external hydrogen embrittlement (EHE / HI-SCC)

installation overload + timber swelling Foverstress + Fsw internal hydrogen embrittlement (IHE)

installation overload Foverstress

t=0 INSTALLATION

days

2026

weeks

months

years

On site, examination of failed samples, the fracture surface and marks on the fastener can provide initial indications of the cause of failure. However, failures should always be assessed with the support of specialists. In most cases, laboratory analysis is required to reliably identify the actual failure mechanism. The main signs to be identified on site for the correct analysis and interpretation of the phenomenon are listed below.

SIGNS OF TIMBER MOISTURE These indicate the extent of exposure to rainfall and are associated with shank corrosion and possible overloads caused by timber swelling.

66 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

SIGNS OF CORROSION Corrosion (white or red) on the surface of the shank may indicate excessive exposure to an aggressive environment. Corrosion on the fracture surface can develop within a few hours and is therefore not necessarily indicative of the cause of failure.

SIGNS OF WEAR OR DAMAGE Marks on the screw coating or on the supporting material may indicate deviations from the recommended insertion angle or installation overloads.

FRACTURE SURFACE MORPHOLOGY May provide useful indications regarding the failure mechanism. In general: • circular patterns indicate torsional overload; • linear patterns and elongated lips indicate tensile overload; • patterns that are both circular and elongated indicate the combined presence of torsional overload and tensile overload; • failure of the screw head may be associated with an incorrect insertion angle; • predominantly flat surfaces, possibly showing signs of corrosion, may indicate brittle failure, including hydrogen-embrittlement-related failure in the presence of overloads.

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 67

INSPECTION FAILED: REMEDIAL ACTIONS There is no single solution that is suitable for all cases. Where broken screws, torsional overload, damage to the internal thread in the timber, or red rust corrosion are present, the repair strategy must be assessed on a case-by-case basis. In more complex cases, support from the Rothoblaas technical consultancy service is recommended. Several possible strategies are outlined below:

MODIFICATION OF THE NAILING LAYOUT If the connector includes unused holes, the non-compliant screw can be removed and replaced with a new screw of the same size in one of the adjacent unused holes. This is a typical case for plates with partial fastening patterns (perforated steel straps, angle brackets, etc.).

The same principle can also be applied to non-standard plates. In these cases, there are generally no unused or available holes; modifying the fastening pattern is therefore not always possible and it is often necessary to drill a new hole in the plate. In these situations, the new holes should be positioned in a staggered arrangement relative to the existing fasteners, while always respecting the minimum spacing requirements. It is good practice to fill unused holes with epoxy resin to restore the damaged timber grain.

ROTHOBLAAS RECOMMENDS XEPOX TWO COMPONENTS EPOXY ADHESIVE

68 | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | CONNECTIONS

REPLACING A NON-COMPLIANT SCREW WITH A LARGER-DIAMETER SCREW Where the fastener cannot be relocated to an alternative hole, replacement with a larger-diameter fastener may be considered, subject to enlargement of the hole in the plate. As a general rule, reinserting a screw of the same type, diameter and length is not considered reliable. The decision whether to replace only the damaged fastener or to adopt a more extensive remedial solution should be carefully assessed. REPLACEMENT WITH LARGER SCREWS: nominal diameter of screw to be replaced ≤ pilot-hole diameter for new screw screw to be replaced LBS Ø7

d1 = 7,0 mm

new screw VGS Ø13

≤

dV = 8,0 mm

REPLACEMENT WITH LARGER BOLTS OR THREADED RODS: nominal diameter of screw to be replaced ≤ nominal diameter of new bolt/threaded rod screw to be replaced HBS PLATE Ø8

d1 = 8,0 mm

new bolt KOS M10

≤

d = 10,0 mm

WARNING! In all cases, the new solution must be verified by the designer with regard to load-bearing capacity, stiffness, ductility, geometry, corrosion resistance, minimum spacing requirements, etc.

CONNECTIONS | INSTALLATION AND INSPECTION OF FASTENING SYSTEMS | 69

MEMBRANES AND TAPES

MEMBRANES AND TAPES Proper design of protection systems and airtight, watertight and vapour-control layers requires a preliminary assessment of the construction element and exposure conditions. The choice of solutions is never arbitrary and directly affects performance, flow control and the durability of the building envelope.

ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS

from page 72

SITE PROTECTION: SYSTEM SELECTION

from page 82

VAPOUR CONTROL MEMBRANES

from page 94

WINDTIGHT MEMBRANES

from page 106

INSTALLATION OF TAPES, MEMBRANES AND FOAMS

from page 118

MEMBRANES AND TAPES | 71

ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS

This chapter presents the analysis of a typical construction site, with the aim of identifying the areas most exposed to risk and defining appropriate mitigation measures. The content revisits and summarises the topics covered in other chapters, highlighting the need to adapt solutions to the specific context. Not all areas of a construction site present the same level of risk: some require greater attention and more targeted measures. In particular, this chapter refers to and expands upon the following topics: • Critical connections: identification and inspection (page 34) • Selection of site protection systems (page 82) • Selection of the correct membrane (page 94) • Correct installation of tapes, membranes and foams (page 118) • Rainwater drainage and deflection (page 156) The images use a colour-coding system to facilitate the understanding and interpretation of the proposed solutions: • Green: generic tapes to be applied on site; • White: temporary site protection membranes, including the complete system (membrane, tapes and overlaps); • Grey: membranes specified by the designer for moisture control, airtightness and windtightness, which also provide temporary protection. The base connection of the structural elements is not shown in the diagrams. For further details, see the chapter “BASE CONNECTIONS: JUNCTION DESIGN” on page 130.

RISK ASSESSMENT low risk

medium risk

high risk

very high risk

SITE ANALYSIS AND MANAGEMENT OF HIGH-RISK AREAS ASSEMBLY OF THE FIRST STOREY OF THE STRUCTURE The entire timber surface is exposed to water. In the event of rain, the elements will start to become wet. During the initial stage, the most sensitive areas are surfaces with exposed timber grain, such as: • column tops • window openings • exposed ends of CLT walls. Where present, the lift shaft tends to accumulate water internally in an area with limited ventilation and slow drying.

74 | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | MEMBRANES AND TAPES

If the CLT panels arrive on site already waterproofed, they are protected from water ingress. However, temporary site protection systems alone are not sufficient to eliminate all risks. It remains essential to dry the structure after rainfall and to provide suitable drainage paths for water run-off.

See further details under "SITE PROTECTION: SYSTEM SELECTION" on page 82

ROTHOBLAAS RECOMMENDS DEFENCE ADHESIVE REMOVABLE REMOVABLE SELF-ADHESIVE PROTECTIVE MEMBRANE

MEMBRANES AND TAPES | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | 75

ASSEMBLY OF THE SECOND STOREY OF THE STRUCTURE The upper storeys cover and protect the lower levels. The perimeter areas and the joints between panels remain exposed. The lift shaft acts as a sump: the collected water is unable to dry because the area remains permanently shaded and poorly ventilated. Column tops are particularly exposed to water, and enclosed spaces dry with difficulty.

ROTHOBLAAS RECOMMENDS DEFENCE ADHESIVE SELF-ADHESIVE PROTECTIVE MEMBRANE FOR BUILDING ELEMENTS

76 | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | MEMBRANES AND TAPES

The structure remains protected even when water is present; nevertheless, any build-up must be removed.

ROTHOBLAAS RECOMMENDS CAP TOP TARPAULIN FOR ROOFS

MEMBRANES AND TAPES | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | 77

ASSEMBLY OF A PITCHED ROOF Once installed, the roof protects the storeys below from weather exposure. However, the perimeter zones of the building remain exposed and represent areas of increased risk.

WATER BEHAVIOUR ON PITCHED ROOFS On pitched roofs, rainwater naturally drains away without creating standing water, a condition that is generally favourable for the durability of the roofing system. Particular attention should nevertheless be paid to eaves gutters, where water may accumulate and increase the risk of water ingress.

78 | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | MEMBRANES AND TAPES

EAVES GUTTERS: CRITICAL ISSUES AND REQUIREMENTS Eaves gutters are critical areas during the construction stage. They are frequently used as access routes and for the temporary storage of roofing materials, making them subject to greater mechanical stress and reduced drying capacity. Eaves gutters must therefore be adequately protected with multiple protective layers to increase the mechanical strength of the system and prevent damage to waterproofing membranes.

MEMBRANES AND TAPES | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | 79

ASSEMBLY OF A FLAT ROOF For flat roofs, local falls should be incorporated into the load-bearing structure to facilitate drainage and reduce the risk of standing water during construction. Providing structural falls reduces the risk of water pooling, but this measure alone is not sufficient.

ROTHOBLAAS RECOMMENDS SMART BAND UNIVERSAL SINGLE-SIDED TAPE WITH SEPARABLE LINER

80 | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | MEMBRANES AND TAPES

Rapid waterproofing of the structure is essential, either through the application of temporary protection during panel production or through the prompt installation of vapour control membranes on site. Appropriate solutions for the drainage of rainwater must also be provided at structural level.

See further details under “RAINWATER DRAINAGE AND DEFLECTION” on page 156

ROTHOBLAAS RECOMMENDS RAIN TUBE TEMPORARY DOWNPIPE FOR CONSTRUCTION SITE PHASES

MEMBRANES AND TAPES | ASSESSMENT OF THE STRUCTURAL ELEMENT AND CRITICAL AREAS | 81

SITE PROTECTION: SYSTEM SELECTION The selected level of site protection depends on exposure to weather conditions and the acceptable level of risk.

RISK MATRIX

very low risk

low risk

medium risk

high risk

risk to be avoided

SITE PROTECTION

LOCAL

SURFACE

TOTAL

EXPOSURE LEVELS

short-term exposure and a low-rainfall climate

long-term exposure or a very rainy and/ or humid climate

long-term exposure and a very rainy and/or humid climate

A thorough risk assessment makes it possible to choose the most suitable solution, identifying the right balance between project execution costs and the required level of protection.

82 | SITE PROTECTION: SYSTEM SELECTION | MEMBRANES AND TAPES

PROTECTION OF END-GRAIN SECTIONS AND SENSITIVE ELEMENTS

LOCAL

The timber is exposed to weather conditions and only the parts most susceptible to capillary uptake are protected. In the event of rain, remove water from timber elements to prevent standing water on surfaces and panel end-grain sections.

SURFACE

PROTECTION OF TIMBER ELEMENTS WITH TEMPORARY TARPAULINS OR ADHESIVE MEMBRANES The timber is protected, but the membrane remains exposed to weather conditions. In the event of heavy rain, installation errors or standing water, the timber may absorb moisture. It is therefore necessary to remove water from timber elements to prevent standing water on surfaces and panel end-grain sections.

TOTAL

PROTECTION USING A TEMPORARY STRUCTURE The construction site is protected from weather conditions throughout all stages of assembly. Even in the event of heavy rainfall and/or extended construction periods, the timber structure remains protected from direct contact with water.

MEMBRANES AND TAPES | SITE PROTECTION: SYSTEM SELECTION | 83

LOCAL PROTECTION PROTECTION OF END-GRAIN SECTIONS AND SENSITIVE ELEMENTS The timber is exposed to weather conditions and only the parts most susceptible to capillary uptake are protected.

AREAS SENSITIVE TO CAPILLARY UPTAKE: end-grain sections End-grain sections absorb more water due to capillary uptake and are therefore particularly vulnerable.

DOOR AND WINDOW OPENINGS Door and window openings increase the risk of water absorption and may promote localised standing water, making these areas particularly critical.

MATERIALS WITH HIGHER WATER ABSORPTION: OSB Some materials, such as OSB, absorb more water than solid timber and, when exposed to moisture, may swell and experience reduced mechanical performance.

84 | SITE PROTECTION: SYSTEM SELECTION | MEMBRANES AND TAPES

AREAS SUBJECT TO STANDING WATER AND WITH LIMITED DRYING POTENTIAL: SMALL GAPS Small gaps and notches can create areas where water accumulates and is difficult to dry.

ROTHOBLAAS RECOMMENDS TITAN PLATE T PLATES FOR TIMBER Reduction in complex processing and easier installation Reduced risk of standing water at joints Creation of diaphragm-action floors and restoration of continuity between adjacent panels Design and application versatility thanks to the possibility of using LBA nails or LBS screws with diameters of 5 or 7 mm, with full or partial fastening patterns

TIMBER IN CONTACT WITH MOIST MATERIALS OR MOISTURE-SENSITIVE COVERINGS: screeds or prefabricated plasterboard panels exposed to weather conditions Moisture-sensitive coverings may absorb water and transfer it to adjacent timber, which tends to become wet and remain damp for extended periods due to limited ventilation and the difficulty of drying the outer layers.

DID YOU KNOW THAT... DEFENCE and INVISI BAND products are semi-transparent, allowing any on-site water ingress or problems to be immediately identified. DEFENCE ADHESIVE REMOVABLE can also be used for temporary applications on non-visible elements: the ideal solution where adhesives need to be applied or where subsequent construction phases require direct fastening to the timber.

MEMBRANES AND TAPES | SITE PROTECTION: SYSTEM SELECTION | 85

T TE S

PROTECTION WITH ADHESIVE MEMBRANES The choice of adhesive membrane varies according to external conditions and the moisture content of the timber. To determine the most suitable solution, three types of membrane were tested on timber in three different service classes, identifying the best combination for each site scenario.

TIMBER CONDITIONING service class 1:

SC1 drySC2 timber SC3

SC4

(moisture content 10-12%)

SC1

service class 2:

SC2 moist SC3timber SC4

SC1

(moisture content 16-20%)

service class 3:

SC2

timber SC3 wet SC4

(moisture content > 20%)

The timber samples were conditioned to three different initial moisture contents and subsequently covered with the various adhesive membranes.

SCENARIO 1: membrane applied off site

SCENARIO 2: membrane applied on site under dry conditions

timber exposure conditions:

SC1

timber exposure SC2 SC3 SC4 conditions:

initial timber moisture:

10%

initial timber moisture:

BARRIER ALU NET ADHESIVE 300

SCENARIO 3: membrane applied on site under wet conditions

SC2

timber exposure SC3 SC4 SC1 conditions:

16%

initial timber moisture:

SC1

BARRIER ALU NET ADHESIVE 300

DEFENCE ADHESIVE products

SC2

SC3

23%

BARRIER ALU NET ADHESIVE 300

DEFENCE ADHESIVE products

DEFENCE ADHESIVE TRASPIR EVO

timber without membrane

SIMULATION OF THE CONSTRUCTION STAGE All samples were then placed in a climate chamber to reproduce two different environmental conditions and assess their behaviour over time.

UNFAVOURABLE SITE CONDITIONS (humid environment) exposure conditions:

FAVOURABLE SITE CONDITIONS (drying possible) exposure conditions:

temperature

20°C

temperature

20°C

relative air humidity

75% UR

relative air humidity

50% UR

duration

17 days

duration

17 days

86 | SITE PROTECTION: SYSTEM SELECTION | MEMBRANES AND TAPES

SC4

S TE T

KEY FINDINGS BARRIER ALU NET ADHESIVE 300 (vapour barrier)

DEFENCE ADHESIVE (vapour control layer)

timber without membrane

transition from unfavourable to favourable conditions

DEFENCE ADHESIVE TRASPIR EVO (breathable)

SCENARIO 1: membrane applied off site When the membrane is applied off site, with the timber moisture content controlled and no damage anticipated during construction, Rothoblaas recommends the use of DEFENCE ADHESIVE, which ensures effective protection and keeps the panel dry.

moisture content (%)

21 19 17 15 13 11 9

20 days

SCENARIO 2: membrane applied on site under dry conditions For on-site applications on dry panels, or in the event of minor accidental damage, Rothoblaas recommends DEFENCE ADHESIVE TRASPIR EVO, which protects the timber while allowing residual vapour diffusion, promoting proper drying of the material.

moisture content (%)

21 19 17 15 13 11 9

days

SCENARIO 3: membrane applied on site under wet conditions If the panels are wet, they should be left to dry for a period before applying the membrane. DEFENCE ADHESIVE TRASPIR EVO protects the timber from subsequent weather exposure while facilitating the dissipation of residual moisture.

moisture content (%)

21 19 17 15 13 11 9

days Note: The moisture content of the timber was always determined on a mass basis and verified using a moisture meter.

MEMBRANES AND TAPES | SITE PROTECTION: SYSTEM SELECTION | 87

T TE S CONCLUSIONS: MEMBRANE SELECTION MATRIX

very low risk

risk to be avoided

SC1

low risk

medium risk

high risk

service class 1: dry timber SC2 SC3 SC1 SC4 SC2 (moisture content 10-12%)

service class 2: moist timber SC3 SC1SC4 SC2 (moisture content 16-20%)

SC3

service class 3: wet timber SC4 (moisture content > 20%)

SITE CONDITIONS

membrane applied off site

SCENARIO

SC1

SC2

membrane applied on site under dry conditions SC1

SC2

SC3

cold and humid climate with low rainfall

humid climate with moderate rainfall

BARRIER ALU NET ADHESIVE 300

DEFENCE ADHESIVE TRASPIR EVO

DEFENCE ADHESIVE

DEFENCE ADHESIVE SC3 SC4 TRASPIR EVO

DEFENCE ADHESIVE TRASPIR EVO

BARRIER ALU NET ADHESIVE 300

DEFENCE ADHESIVE

DEFENCE ADHESIVE TRASPIR EVO

DEFENCE ADHESIVE

DEFENCE ADHESIVE TRASPIR EVO

very humid climate with high rainfall

BARRIER ALU NET ADHESIVE 300

DEFENCE ADHESIVE TRASPIR EVO SC3 SC4

membrane applied on site under wet conditions SC1

hot climate with low rainfall

DEFENCE ADHESIVE TRASPIR EVO

SC4

CLIMATE CHAMBER TESTING

Timber conditioning

Simulation of the construction stage

88 | SITE PROTECTION: SYSTEM SELECTION | MEMBRANES AND TAPES

S TE T

MEMBRANE DAMAGED DURING CONSTRUCTION During construction, protective membranes may be accidentally damaged due to material handling, site traffic, or the installation of fastening elements.

TEST CONDITIONS A preliminary test was conducted to assess the effects of different types of damage.

CASE 1

CASE 2

CASE 3

Damage caused by the insertion of 4 inclined screws.

Damage caused by the installation Damage resulting from surface of a plate fastened with screws. abrasion, foot traffic and minor accidental tears.

SIMULATION OF THE CONSTRUCTION STAGE The specimens were exposed to weather conditions for approximately 35 days under alpine spring climate conditions (April–June). During this period, they were subjected to day-night cycles with significant temperature fluctuations, rainfall and subsequent drying periods.

35 days

Note: The moisture content of the timber was always determined on a mass basis and verified using a moisture meter.

MEMBRANES AND TAPES | SITE PROTECTION: SYSTEM SELECTION | 89

T TE S IMPLICATIONS ACCORDING TO THE TYPE OF DAMAGE The preliminary test shows that DEFENCE ADHESIVE TRASPIR EVO, thanks to its breathability, promotes more effective timber drying and limits moisture-related damage. The different types of damage give rise to specific issues: • CASE 1: a condition particularly susceptible to water ingress; consequently, additional tests were carried out to investigate waterproofing performance; • CASE 2: increased risk associated with potential timber swelling; • CASE 3: highly variable behaviour that is difficult to reproduce; for water ingress, refer to CASE 1.

MEMBRANE DAMAGE IN THE PRESENCE OF SCREWS To evaluate membrane performance under these conditions, tests were carried out with screws inserted to simulate potential water ingress beneath the protective layer.

TEST CONDITIONS

initial timber moisture content screw insertion method

10% WITHOUT PRE-DRILLED HOLE WITH PRE-DRILLED HOLE

SIMULATION OF THE CONSTRUCTION STAGE The test procedure involves inserting 45° inclined screws, creating a larger-diameter hole and lifting the underlying timber grain, thereby creating a potential path for water ingress. Coloured water is then applied to simulate prolonged exposure to rain during construction. After one week, the remaining water is removed and the level of water ingress and drying time of the timber element are assessed.

Note: The timber moisture content was measured at various locations using a moisture meter.

90 | SITE PROTECTION: SYSTEM SELECTION | MEMBRANES AND TAPES

S TE T

KEY FINDINGS Mapping of water ingress beneath the membrane. WITHOUT PRE-DRILLED HOLE

WITH PRE-DRILLED HOLE

Wood fibres break more easily, creating an irregular Controlled screw insertion reduces local stress and hole that is more susceptible to deformation. limits grain damage. CONCLUSIONS Assessment of the drying behaviour of the timber specimen after removal of surface water. LEGEND:

moisture content (%)

installation with pre-drilled hole

installation without pre-drilled hole

25 20

drying trend with screws inserted into pilot holes

15 10

drying trend with screws inserted without pilot holes

5 0

days

The presence of a pilot hole limits water ingress beneath the membrane and allows faster drying. The test also shows that, in the event of accidental damage, prolonged exposure to standing water may result in timber moisture content exceeding 30%.

MEMBRANES AND TAPES | SITE PROTECTION: SYSTEM SELECTION | 91

PROTECTION WITH TARPAULINS For small to medium-sized construction sites, or for parts of larger structures, temporary covering tarpaulins can be used to provide temporary protection during construction.

Fast installation Quick to install, even for short-term use (e.g. overnight), providing immediate protection against unexpected rainfall.

Weather protection The tarpaulin must be properly secured to ensure stability, even in adverse weather conditions.

Fastening eyelets Possibility to properly secure the tarpaulin to the roof structure.

Tarpaulin selection The choice of tarpaulin depends on the intended period of use, the area to be covered, the level of risk, the expected severity of adverse weather conditions and the available budget.

Reusable Can also be reused on subsequent construction sites.

Crane lifting hook On heavier-duty versions, the hook facilitates installation and removal on larger, more organised construction sites.

92 | SITE PROTECTION: SYSTEM SELECTION | MEMBRANES AND TAPES

ROTHOBLAAS RECOMMENDS

CAP TOP

TARPAULIN FOR ROOFS

Each size is equipped with a reinforced lifting hook for easier installation. Thanks to the metal fastening eyelets every metre, it is possible to fix the tarpaulin to the roof. The large mass per unit area and the type of material guarantee better mechanical resistance and durability over time. When fixing the tarpaulin to the roof it is important that all eyelets are always anchored so that the wind load is spread over as many eyelets as possible.

CAP PLUS

TARPAULIN FOR ROOFS

CAP PLUS tarpaulin for construction sites protects roofs and work areas from the weather. With a mass per unit of 300 g/m2, it has good mechanical strength characteristics both to traction and tearing. It is available in various sizes.

CAP ECO

TARPAULIN FOR ROOFS

CAP ECO is the tarpaulin for roofs for construction sites with a mass per unit of 210 g/m2 . Available in two sizes, it is particularly resistant to UV rays thanks to the black inner support. It is easily and quickly fixed to the roof by means of the metal eyelets arranged every metre. CAP ECO, the simple and effective solution to cover the building site protecting it from the weather.

MEMBRANES AND TAPES | SITE PROTECTION: SYSTEM SELECTION | 93

VAPOUR CONTROL MEMBRANES The building envelope is subject to continuous flows of heat, vapour, air and wind which, if not properly controlled, compromise the performance of building components. The properties of membranes are defined by the CE marking standards: EN 13984 for vapour control membranes, EN 13859-1 for underlays for discontinuous roof coverings, and EN 13859-2 for wall underlays. The classification of membranes according to their Sd values is not uniform, as it depends on individual national regulations.

PROPERTIES Membranes can be divided into three main categories according to their hygrothermal behaviour.

PROTECTION

0,0

BARRIER VAPOR

-0,5

protection(1)

Behaviour of a dry material exposed to a humid environment

-1,0 -1,5

TRASPIR

-2,0 -2,5 -3,0 -3,5 0

days

DRYING

TRASPIR

3,5

Behaviour of a moist material in a dry environment

3,0

drying(2)

2,5 2,0 1,5 1,0

VAPOR

0,5

BARRIER

days

The graphs are based on the results of the test campaign described on page 86. (1) Reduction in protection due to moisture absorbed by the CLT panel. (2) Drying capacity of the CLT panel with membrane applied.

94 | VAPOUR CONTROL MEMBRANES | MEMBRANES AND TAPES

watertightness

vapour transmission

airtightness

windtightness

BARRIER

VAPOR

TRASPIR

prevents water transmission

prevents vapour transmission

limits vapour transmission

allows vapour transmission

prevents drying

limits drying

allows drying

BARRIER membranes provide a high level of resistance to vapour transmission, but they do not allow materials to dry after exposure to rain during construction or following installation errors.

MEMBRANES AND TAPES | VAPOUR CONTROL MEMBRANES | 95

RISK OF CONDENSATION To reduce the risk of condensation, vapour control membranes should be installed on the warm side of the building element, limiting moisture migration through the building element. On the cold side, insulation layers and breathable materials should be positioned to maintain the build-up at a higher temperature and promote the dissipation of residual vapour.

LEGEND: vapour

heat

COLD SIDE

WARM SIDE insulating material

internal covering

Sd λ

Sd external cladding

BARRIER VAPOR

TRASPIR

structure

OUTDOOR TRASPIR

Sd λ

BARRIER VAPOR external cladding

internal covering

insulating material Sd

INTERNAL

96 | VAPOUR CONTROL MEMBRANES | MEMBRANES AND TAPES

COLD SPOTS

HIGH MOISTURE LEVELS

Thermal bridges are geometric or material discontinuities within the building envelope that alter the temperature distribution within building components. When the surface temperature falls below the dew-point temperature, the risk of surface condensation and mould growth increases; if this occurs within the build-up, interstitial condensation can occur, causing damage to the materials.

When moisture levels within materials or indoor environments are very high, the risk of mould and component degradation increases significantly. The main causes include the absence of membranes that limit moisture accumulation within the build-up, ground-bearing floors or basements that transfer moisture to upper storeys, rising damp, water ingress, leaks from building services, and insufficient ventilation.

temperature

25° C

14° C

25° C

absolute humidity

11,5 g/m3

23 g/m3

relative humidity

50%

100%

50%

100%

Absolute humidity depends solely on the quantity of water vapour present in the air, whereas relative humidity depends on both the amount of water vapour and the air temperature. As temperature rises, the air can hold more water vapour and the relative humidity decreases.

From theory to installation On the Rothoblaas BLOG you’ll find technical articles on waterproofing to guide you in your on-site choices.

Here you will find technical articles, practical applications, and case studies rothoblaas.com

MEMBRANES AND TAPES | VAPOUR CONTROL MEMBRANES | 97

MEMBRANE SELECTION ACCORDING TO CLIMATE ZONE The most suitable solution depends on several factors: climatic conditions, the construction system used and the intended application. To support the design stage, a dedicated tool is available on the Rothoblaas website, enabling users to identify the most suitable build-up for a specific project in just a few steps.

ARCTIC CLIMATE

TEMPERATE WARM CLIMATE

COLD CLIMATE

WARM CLIMATE

TEMPERATE COOL CLIMATE

HOT CLIMATE

98 | VAPOUR CONTROL MEMBRANES | MEMBRANES AND TAPES

HOT CLIMATE

The right membrane for your project Choose the ideal membrane according to the climate zone and construction system.

Find our tips at: rothoblaas.com MEMBRANES AND TAPES | VAPOUR CONTROL MEMBRANES | 99

CLIMATIC CONDITIONS The typical behaviour of building elements varies according to the climatic context. The information provided is intended as general guidance only: the final selection of materials and arrangement must always be verified through project-specific hygrothermal simulations.

LEGEND: °C

°C

very cold and dry

room temperature

°C

cold and dry

hot and humid

warm

cold and dry (air-conditioned)

vapour

vapour flow direction

COLD CLIMATES High risk of interstitial condensation in winter.

OUTDOOR °C

°C

INDOOR °C

°C

COLD SPOT: condensation risk

A significant difference in temperature and humidity between the interior and exterior drives vapour migration through the building element towards colder areas, where it may reach the dew-point and condense.

OUTDOOR °C

INDOOR °C

°C

TRASPIR windtightness

°C

BARRIER VAPOR IN vapour management airtightness

Vapour barriers and vapour control layers on the warm side limit vapour flow, while the breathable membrane on the external side allows residual vapour to escape without condensing within the build-up.

In particularly cold and humid climates near coastlines or watercourses, it may be beneficial to provide a vapour control layer on the external side as well.

100 | VAPOUR CONTROL MEMBRANES | MEMBRANES AND TAPES

TEMPERATE CLIMATES Vapour migrates in winter, with drying potential in summer.

OUTDOOR °C

INDOOR °C

°C

TRASPIR windtightness

°C

OUTDOOR °C

INDOOR

°C

VAPOR CLIMA CONTROL vapour management airtightness

TRASPIR drying windtightness

A smaller temperature difference between the interior and exterior reduces vapour flow through the building element. To prevent condensation, a vapour control layer or a variable-permeability membrane is generally sufficient.

°C

VAPOR CLIMA CONTROL airtightness

Any moisture accumulated within the build-up may dry out during the summer season, because of warmer and drier conditions that promote vapour migration.

HOT / TROPICAL CLIMATES Risk of interstitial condensation in summer.

OUTDOOR °C

INDOOR

°C

OUTDOOR °C

°C

TRASPIR ALU CLIMA CONTROL vapour management or temperature control windtightness

COLD SPOT: condensation risk

Vapour flow occurs from the warm, humid exterior towards the cool, air-conditioned interior.

INDOOR °C

°C

TRASPIR CLIMA CONTROL airtightness

CLIMA CONTROL adapts to the hygrothermal conditions within the materials, providing protection while promoting drying. TRASPIR ALU reflects the heat, reducing the surface temperature of materials.

The reliability of these recommendations depends on the level of air conditioning and the temperature difference between the interior and exterior environments. Pronounced day-night temperature fluctuations introduce additional variations in vapour transport mechanisms, increasing uncertainty regarding the hygrothermal behaviour of the build-up.

MEMBRANES AND TAPES | VAPOUR CONTROL MEMBRANES | 101

FLAT ROOF CONDENSATION RISK OUTDOOR °C

°C

WATER INGRESS RISK

°C

INDOOR

OUTDOOR

waterproofing membrane (vapour barrier)

°C

COLD SPOT where moisture accumulates

°C

Low roof pitch and risk of standing water.

INDOOR

BARRIER OUTDOOR CLOSED SYSTEM: °C °C high protection, no drying potential. BARRIER on the internal side: prevents vapour transmission and avoids the formation of condensate. This case can be simulated under steady-state conditions (Glaser method) to assess condensation phenomena under average, constant climatic conditions.

Note: all membrane penetrations caused by fasteners must be°C sealed with tapes and nail-sealing products to ensure continuity of the layer and maintain the integrity of the vapour barrier.

waterproofing membrane (vapour barrier)

°C

BARRIER

INDOOR

OUTDOOR °C

°C

INDOOR

OUTDOOR °C

°C

OUTDOOR condensation point

°C

INDOOR

°C

INDOOR

Rainwater during construction re- Installation defects in the vapour Water ingress is not visible, it can mains trapped. barrier may cause localised con- trap moisture. densation problems.

102 | VAPOUR CONTROL MEMBRANES | MEMBRANES AND TAPES

CLIMA CONTROL SMART SYSTEM: medium protection, medium drying potential. CLIMA CONTROL: limits vapour transmission during winter and promotes drying during summer. This case must be simulated under dynamic conditions, because it considers actual variations in temperature and humidity over time and provides a more accurate assessment, including drying processes.

OUTDOOR °C

°C

OUTDOOR

°C

vapour control layer in winter

INDOOR

OUTDOOR

breathable in summer

OUTDOOR

°C

INDOOR

Non-breathable insulation materials do not allow drying.

Limited sunlight exposure during summer inhibits drying processes.

See further details under “RAINWATER DRAINAGE AND DEFLECTION” on page 156

DID YOU KNOW THAT... For flat timber roofs, it is preferable to provide an exposed load-bearing structure with continuous boarding, as this limits the accumulation of moisture within the structure and provides favourable conditions for inspecting and drying of timber elements, avoiding closed, non-inspectable assemblies.

For further information on CLIMA CONTROL testing, refer to the catalogue “TAPES, MEMBRANES, SEALANTS AND FIRE PROTECTION”, available at www.rothoblaas.com.

MEMBRANES AND TAPES | VAPOUR CONTROL MEMBRANES | 103

Membrane correctly installed with adequate over- A Blower-Door test carried out at an intermediate laps and properly taped joints, ensuring layer conti- stage, are installed before building services and finnuity and airtightness. ishes, to verify the continuity of the airtight layer.

Self-adhesive barrier applied under suitable weather conditions, with continuous installation and correctly executed overlaps.

104 | VAPOUR CONTROL MEMBRANES | MEMBRANES AND TAPES

Vapour barrier installed without taped joints, potentially Vapour barrier damaged at multiple points by buildreducing airtightness and vapour-control performance. ing services and untaped fasteners, without restoring layer continuity.

For further details, refer to “RECOMMENDATIONS FOR INSTALLATION: INTERNAL MEMBRANES”. Available in the Catalogues section at www.rothoblaas.com.

Vapour barrier extensively damaged and repaired only locally, with discontinuous remedial work reducing the effectiveness of the layer.

MEMBRANES AND TAPES | VAPOUR CONTROL MEMBRANES | 105

WINDTIGHT MEMBRANES

11 CHOOSE HIGH-QUALITY (MONOLITHIC) MEMBRANES Certified and tested membranes designed to withstand weather exposure provide protection and durability. The use of monolithic membranes and higher grammage membranes increases durability and abrasion resistance, reducing the risk of damage.

Low-cost or non-certified products deteriorate rapidly and do not provide adequate protection.

2 PLAN THE CONSTRUCTION STAGE TO LIMIT WEATHER EXPOSURE Limit exposure to prevent premature membrane degradation and reduce stress on taped joints. Reduce the risks associated with severe weather events and carry out installation in dry conditions, avoiding strong winds and rain to prevent moisture from becoming trapped within the build-up.

Prolonged exposure accelerates membrane degradation, increases stress on taped joints and heightens the risks associated with repeated weather events. Strong winds, cloudbursts, thunderstorms and exceptional weather events during construction increase the risk of damage and water ingress.

3 ENSURE MEMBRANE CONTINUITY Layer continuity is ensured through overlaps appropriate to the roof pitch, correctly executed taping, and sealing of all penetrations in the membrane, including those created by fasteners.

Unsealed and untaped overlaps compromise continuity, airtightness and watertightness, promoting water ingress and premature deterioration.

4 DESIGN VENTILATED SYSTEMS AND PREVENT OVERHEATING An effective ventilation system promotes heat dissipation and rapid drying of the build-up.

Insufficient or absent ventilation causes overheating, accelerates degradation and reduces drying capacity.

5 CHOOSE COMPATIBLE SUBSTRATES 5

Use a stable, compliant substrate (such as. panels, even surfaces, membranes), free from chemicals, oils, grease and solvents.

An uneven or incompatible substrate can cause wrinkling, stress concentrations and loss of performance. The presence of chemicals, oils, grease and solvents may compromise the functional film.

106 | WINDTIGHT MEMBRANES | MEMBRANES AND TAPES

VENTILATED FAÇADE OPEN-JOINTED FAÇADES: PROTECT AGAINST UV RAYS

A membrane certified for UV exposure remains sta- A membrane that is not UV-resistant will deteriorate ble over time. prematurely and lose performance.

CLOSED-JOINTED FAÇADES: PROTECT THE INSULATION LAYER

A breathable membrane ensures protection and durability of the entire assembly, even in the event of accidental damage or minor water ingress.

Without a membrane, the façade is exposed to water ingress and deterioration of the insulation layer's performance.

See further details under “INSTALLATION OF TAPES, MEMBRANES AND FOAMS" on page 118

MEMBRANES AND TAPES | WINDTIGHT MEMBRANES | 107

DISCONTINUOUS ROOFING ASSESS THE ROOF SLOPE LENGTH

L = > 10 m

L = < 10 m

Roof slopes of limited length (<10 m) facilitate installation and reduce stresses on the system.

Long roof slopes (>10 m) increase the risk of membrane sagging and slippage and require reinforced fasteners and particular attention to taped joints.

ASSESS THE FINAL WATERPROOF LAYER

A new roof covering the compliant with specifications (e.g. tiles or metal) provides optimum protection.

Refurbished roof coverings, or coverings with non-watertight elements (e.g. shingles), roof pitches below the certified minimum increase the risk of water ingress.

108 | WINDTIGHT MEMBRANES | MEMBRANES AND TAPES

CONSIDER THE ROOF PITCH

> 16,7°

< 16,7°

A pitch roof >30% (≈16.7°) promotes rapid water runoff. For lower pitches, membranes with a higher mass per unit area and increased overlap widths are required.

A pitch roof <30% slows water run-off and increases the risk of water ingress. Steep pitches combined with poor membrane mechanical performance increase the risk of tearing.

ASSESS ROOF COMPLEXITY

Simple, linear roof geometries facilitate installation and reduce the risk of errors. Complex geometries (e.g. eaves gutters, corners and junctions) require carefully designed details to minimise risk.

Poorly designed complex geometries (e.g. eaves gutters, corners and junctions) increase the risk of standing water and installation defects.

AVOID SNOW BUILD-UP

Snow build-up can be reduced through adequate roof pitch and efficient drainage, preventing buildup and promoting water run-off.

Snow build-up on the roof increases retained moisture and slows water run-off. The risk of water ingress increases particularly where roof the pitche is low, details are complex, ventilation is inadequate, or membranes have not been correctly installed.

MEMBRANES AND TAPES | WINDTIGHT MEMBRANES | 109

LIMIT WEATHER EXPOSURE AND USE MONOLITHIC MEMBRANES

PRESERVE THE MEMBRANE During construction, membranes are exposed to numerous stresses that can compromise their function. Proper on-site management enables the membrane to maintain its performance over time and the durability of the building system.

NEW MEMBRANE CORRECTLY STORED AND TRANSPORTED(*)

MEMBRANE EXPOSED TO UV RAYS DURING CONSTRUCTION

SHORT-TERM WEATHER EXPOSURE

PROLONGED WEATHER EXPOSURE

MEMBRANE SERVICE LIFE

Protected membrane, constant temperatures, no thermal fluctuations, no mechanical stresses.

Hot-cold cycles, roof overheating, lack of ventilation, mechanical stresses caused by wind, etc.

Protected membrane, constant temperatures, no thermal fluctuations, no mechanical stresses.

Hot-cold cycles, roof overheating, lack of ventilation, mechanical stresses caused by wind, etc.

(*) High temperatures, outdoor storage, significant temperature fluctuations and prolonged storage periods

may compromise membrane performance.

110 | WINDTIGHT MEMBRANES | MEMBRANES AND TAPES

MEMBRANE DURABILITY Membranes are plastic materials composed of polymers, molecular chains that determine their strength and flexibility. To ensure long-term membrane durability, it is essential to limit degradation mechanisms caused by exposure to:

°C UV chemical substances

mechanical stress

UV radiation

temperature

CHEMICAL SUBSTANCES Many products commonly found on construction sites can release surfactants that reduce the surface tension of liquids and may compromise the watertightness of membranes.

MICROPOROUS

MONOLITHIC

Substances containing surfactants reduce the surface tension of liquids allowing them to penetrate materials more easily, compromising the watertightness of microporous films.

Monolithic membranes have a continuous functional film: their vapour permeability is linked to a chemical process rather than a porous structure. Consequently, the presence of surfactants does not compromise their watertightness.

SURFACTANTS • detergents and degreasers • lubricants and tool maintenance products • concrete admixtures • solvents and thinners • paints and primers

MEMBRANES AND TAPES | WINDTIGHT MEMBRANES | 111

UV + MECHANICAL STRESS Polymers are sensitive to UV radiation, which can progressively degrade their molecular structure. Exposure to ultraviolet radiation alters the chemical bonds within polymer chains, causing a loss of mechanical strength, increased stiffness, brittleness and colour changes. To ensure durability, high-performance polymers with improved UV resistance (acrylate and monolithic materials) are used and stabilised with additives that disperse solar radiation.

MEMBRANES

MICROPOROUS

MONOLITHIC

Microporous membranes, like traditional rigid plastic clothes pegs, perform well initially but tend to become brittle, develop microcracks and fail when exposed to sunlight for prolonged periods, as their structure is more sensitive to UV rays.

Monolithic membranes, comparable to softer, more flexible clothes pegs, retain their flexibility over time and offer better resistance to solar exposure. The polymers used in monolithic membranes provide superior UV resistance, are not subjected to mechanical stress during the manufacturing process, and retain their elasticity and watertightness even after prolonged exposure.

112 | WINDTIGHT MEMBRANES | MEMBRANES AND TAPES

TAPES Following UV ageing, tapes reinforced with a mesh scrim retain maximum strength that remains almost unchanged compared with unexposed material. The main difference is deformation behaviour: the carrier loses elasticity and the maximum elongation is significantly reduced. The tape fails when it reaches peak load due to rupture of the reinforcing scrim and loss of carrier deformability.

TAPE EXPOSED TO UV RAYS

100

-80

-80 force, F [N]

force, F [N]

TAPE NOT EXPOSED TO UV RAYS

-60 -40 -20

0 0

100 120 140 160 180 200 220

nominal elongation, δ [mm]

100 120 140 160 180 200 220

nominal elongation, δ [mm]

Building envelope Airtightness, wind resistance and fire protection for façades, doors and windows. A well-designed envelope reduces energy consumption, improves comfort and increases the durability of materials.

Reduce risks and improve construction quality rothoblaas.com

MEMBRANES AND TAPES | WINDTIGHT MEMBRANES | 113

HIGH TEMPERATURES + MECHANICAL STRESS °C

Polymers are sensitive to high temperatures because increased molecular chain mobility reduces their stability and mechanical strength. Heat can promote deformation and degradation, resulting in loss of functionality.

MICROPOROUS

MONOLITHIC

During the production of microporous films, the material is stretched, orienting the polymer chains and inducing residual stresses, which increase membrane stiffness. When the membrane is exposed to high temperatures, these stresses may relax and the polymer tends to partially recover its original configuration. The greater thermal sensitivity of microporous membranes compared with monolithic membranes therefore makes them less stable over time.

No mechanical or thermal stresses are applied during the production process of monolithic membranes. In addition, the polymers used in our monolithic films have higher glass transition temperatures, making them more resistant to thermal stress.

DID YOU KNOW THAT... During the production of microporous membranes, stretching of the polymers aligns the molecular chains and makes the material stiffer. When heated, the chains tend to return to their original configuration, causing the material to shrink. In microporous membranes, this movement is restrained by the fasteners, generating stresses that can lead to film rupture.

For further information on this topic, refer to the WCTE paper available at www.rothoblaas.com.

114 | WINDTIGHT MEMBRANES | MEMBRANES AND TAPES

SELECTION BASED ON PERFORMANCE Depending on climatic conditions and the characteristics of the building, certain national standards provide guidance on membrane selection based on type, mechanical performance and grammage. The following practical recommendations have been developed on the basis of the main national guidelines to assist in selecting the most suitable membrane for a project. In adverse site conditions requiring a high level of weather protection, TRASPIR WELD EVO 360 enables the creation of a continuous welded layer with exceptional watertightness. The selection of membranes according to roof pitch is governed by various national standards. These recommendations have been developed to simplify membrane selection and application.

Roof pitches > 80% (38.6°)

Roof pitches < 30% (16,7°)

Tensile strength MD > 300 N/50 mm

Mass per unit area ≥ 200 g/m2

Nail tear resistance > 225 N For façades, the main selection criteria are not mechanical performance but UV stability and fire performance,to limit flame spread.

For further information on TRASPIR WELD EVO 360 testing, refer to the catalogue “TAPES, MEMBRANES, SEALANTS AND FIRE PROTECTION”, available at www.rothoblaas.com.

Rothoblaas membranes Ce-marked that are in accordance with EN 13984 and EN 13859 are waterproofing, airtight and windtight elements capable of draining rainwater in the event of accidental damage to, or displacement of the upper waterproof layer. This is a safety function intended to limit damage and does not replace the final waterproof covering (tiles, metal roofing elements, sheets), which alone is responsible for the watertightness of the roof. For this reason, there is no specific minimum pitch requirement for membranes: the applicable pitch is that required by the selected roofing system.

MEMBRANES AND TAPES | WINDTIGHT MEMBRANES | 115

Adhesive membrane taped at weak points.

Membrane correctly taped around door and window openings.

Membrane correctly installed from the bottom up, with layer continuity ensured by tapes and nail sealing.

116 | WINDTIGHT MEMBRANES | MEMBRANES AND TAPES

Membrane not taped with no nail sealing provided.

Aligned vertical joints create a preferential path for water ingress. Failure to tape ends and fastener penetrations.

No nail sealing, particularly in low-pitch areas.

MEMBRANES AND TAPES | WINDTIGHT MEMBRANES | 117

INSTALLATION OF TAPES, MEMBRANES AND FOAMS Correct installation of membranes and tapes, which provide airtightness, windtightness and vapour control, is essential to the long-term performance of both the build-up and the building itself.

ASSEMBLY TENSION AND OVERLAPS

Provide overlaps of adequate width according to the type detail: • 10 cm - walls, steeply pitched roofs • 20 cm - exposed joints, wall-to-floor junctions, low-pitch roofs.

Ensure continuity of the seal: a single unsealed penetration can compromise the performance of the entire membrane. Pay attention to work carried out after the membrane has been installed (e.g. building services), which may create discontinuities in the sealing layer.

EASY TEAR LINER

For base connections, tapes with a pre-cut or easily divisible release liner facilitate installation.

Adhesive membranes: apply pressure using a roller or broom to achieve proper adhesion to the surface.

Download "Recommendations for installation: INTERNAL MEMBRANES" for full details. Available at www.rothoblaas.com

118 | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | MEMBRANES AND TAPES

Excessive tension: risk of tearing at fastening points due to thermal expansion and contraction. Potential issues may also arise with the adhesion of sealing tapes.

Insufficient tension: formation of depressions that allow water ponding, excessive stress on tapes and nail seals, and increased vulnerability to wind.

PROTECT THE MEMBRANE DURING AND AFTER INSTALLATION Main risks to the membrane between installation and completion of the building assembly:

aggressive chemicals e.g. engine oil

solvent-based products e.g. markers or spray products

mechanical damage e.g. punctures or high-temperature chips

Guidelines for application: a technical reference

Scan the QR code to download rothoblaas.com

MEMBRANES AND TAPES | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | 119

CRITICAL INSTALLATION POINTS Certain junctions are subject to greater mechanical stresses and a higher risk of water exposure. Pay particular attention during installation.

2 1 2 1 3

Use redundant systems. An elastic, deformable tape Use foldable tapes for corner details. facilitates the sealing of weak points.

Pay attention to corners: a tape that does not conform Use a single tape of adequate width rather than multiproperly to the corner is more susceptible to damage. ple narrow tapes placed side by side. Tape joints represent potential weak points.

ROTHOBLAAS RECOMMENDS SMART BAND UNIVERSAL SINGLE-SIDED TAPE WITH SEPARABLE LINER A tape for sealing external doors and windows, compliant with the requirements for external applications. Also suitable in the presence of standing water, heavy rain and penetrations.

Protect end-grain sections and door and window openings with suitable products (e.g. FLASHING TAPE).

120 | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | MEMBRANES AND TAPES

EXPANDING TAPES Verify that the tape is capable of expanding and properly filling corner details.

Join the beginning and end of the tape using a 45° cut to allow proper expansion and an optimal seal.

ROTHOBLAAS RECOMMENDS

EXPAND BAND

WINDOW BAND

SELF-EXPANDING SEALING TAPE

SELF-EXPANDING SEALING TAPE FOR WINDOWS AND DOORS

MEMBRANES AND TAPES | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | 121

ADHESIVE PRODUCT SELECTION The choice of adhesive product depends on its function, the substrate, the application and service temperatures, and the level of exposure to weathering and UV radiation. The selected product must be applied correctly.

PSA — PRESSURE SENSITIVE ADHESIVE To perform properly, adhesive products must be applied using pressure with a roller or spatula.

carrier

adhesive

TYPES OF ADHESIVE Adhesives can be divided into different families, each characterised by specific properties and areas of application. The selection depends on the intended function, substrate, application and service temperatures, and exposure to weather conditions.

ACRYLIC

BUTYL

BITUMINOUS

initial tack maximum adhesion water resistance low temperature performance substrate compatibility

(1)

Performance varies according to the specific adhesive compound formula. (1) See the complete compatibility table in the catalogue “TAPES, MEMBRANES, SEALANTS AND FIRE PROTECTION”.

122 | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | MEMBRANES AND TAPES

(1)

PRIMER: WHEN AND HOW TO USE IT A Primer evens out the substrate and improves adhesion, particularly on porous, rough or difficult-to-clean surfaces. ADHESIVE TYPE

BASE TYPE

• Acrylic primers Compatible with acrylic, polyurethane, MS polymer and butyl adhesives. • Bituminous primers For bituminous systems and butyl tapes or sealants.

• Solvent-based Fast-drying with good wetting properties, even on relatively smooth surfaces. • Water-based Slower-drying, suitable for porous substrates and indoor environments.

Note: apply the adhesive as soon as the primer has dried: the effectiveness of the treatment decreases over time.

ROTHOBLAAS RECOMMENDS PRIMER

PRIMER SPRAY

UNIVERSAL PRIMER FOR ACRYLIC ADHESIVE TAPES

UNIVERSAL SPRAY PRIMER FOR ACRYLIC ADHESIVE TAPES

Compensates for surface irregularities and improves the adhesion of all tapes and adhesives.

Even the roughest and most fibrous surfaces before the application of tapes or sealants.

BYTUM PRIMER

BYTUM SPRAY

UNIVERSAL PRIMER FOR MEMBRANES AND BITUMINOUS TAPES

BITUMINOUS MEMBRANE SEALANT SPRAY

Water-based Forms a durable bonding layer

Can also be used as a primer Adheres to a wide range of material and shapes, including roofs, gutters, terraces, skylights and PVC or metal drainage pipes.

For further information, see the dedicated section in the catalogue “TAPES, MEMBRANES, SEALANTS AND FIRE PROTECTION” available at www.rothoblaas.com

MEMBRANES AND TAPES | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | 123

SURFACE CONDITIONS COMPACT SURFACE The tape must be in contact with the substrate across the entire adhesive surface. Friable, dusty or uneven surfaces drastically reduce the actual contact area.

carrier

adhesive

very compact very smooth

carrier

adhesive

fairly compacted irregular

poorly compacted irregular

When surfaces are poorly bonded or contaminated with residues such as sawdust, dust or oils, the adhesive tends to stick to the surface particles rather than to the stable substrate underneath.

SUBSTRATE MOISTURE

Water film: the tape floats on the Water or trapped moisture: evapwater layer without adhering to the oration causes the tape or adhesive surface. membrane to lift. Even breathable products may initially be affected by this phenomenon.

Prolonged exposure to high humidity: possible rehydration of water-based adhesives and loss of adhesion.

In windy conditions, the acrylic adhesive dries more quickly before bonding and can stress the tape before adhesion is achieved. Work in windy conditions, in short sections and press immediately.

124 | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | MEMBRANES AND TAPES

TEMPERATURE ON-SITE APPLICATION

Before application, check that the air and substrate temperatures fall within the ranges indicated by the manufacturer.

% adhesion

100 75 50 25 0

-10

temperature °C

°C

Excessively high temperatures: the tape softens, shrinks and may form ripples, detaching from the substrate and exposing the adhesive.

°C

Excessively low temperatures: tape and adhesive become rigid, with limited adhesion and reduced ability to accommodate substrate movement. There is a high risk of detachment.

STORAGE Particular attention must also be paid to climatic conditions during storage, and specific precautions must be taken:

°C UV Maintain at the specified temperature

Protect from sunlight

Protect from high humidity

Store in the original packaging until use

Note: limiting the storage period reduces the risk of deterioration and preserves the product’s effectiveness during use.

Prolonged exposure to high temperatures presents a greater risk than exposure to low temperatures.

MEMBRANES AND TAPES | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | 125

POLYURETHANE FOAMS Polyurethane foam is a chemical sealant used for waterproofing, insulating and sealing. It is used in door and window installation to fill gaps and cavities, or to bond different elements, preventing water ingress and air leakage.

HIGH EXPANSION

ROTHOBLAAS RECOMMENDS High volumetric expansion (up to 3 times the applied volume). Ideal for filling large and irregular cavities.

SMART FOAM GENERAL PURPOSE FOAM SEALANT

Typical uses: • wide gaps and air voids • filling service cavities

ROTHOBLAAS RECOMMENDS

LOW EXPANSION Controlled and reduced expansion. Suitable where mechanical stress on materials must be minimised. Typical uses: • door and window installation (window-to-frame joint) • narrow gaps and service penetrations • areas where excessive expansion could cause deformation • improved thermal insulation and acoustic

FIRE FOAM HIGHLY FIRE-RESISTANT SEALING POLYURETHANE FOAM

HERMETIC FOAM SOUNDPROOFING SEALING POLYURETHANE FOAM

ADHESIVES Adhesive foams are specifically formulated for bonding. They have very low expansion and are formulated to ensure high adhesion and long-term stability. They are not suitable where effective sealing is required, as they fill voids. By contrast, sealing foams, even low-expansion ones, are designed to expand and adapt to cavities and do not provide adequate performance bonding.

126 | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | MEMBRANES AND TAPES

TIPS FOR CORRECT APPLICATION BEFORE APPLICATION

SMART FOAM

COLD WATER 18 - 20 °C

HOT WATER

Bring the canister temperature to the ideal application range

Clean the surface

1 dL

FOAM SMART 15 - 20

Shake at least 15 to 20 times before use

Moisten the surface

Do not fill the entire cavity: the foam expands up to 3 times the applied volume. Fill approximately twothirds of the cavity.

AFTER APPLICATION

CLE FOAM

ANER

CL FO AM

R NE

EA N

AM FO

Clean both the inside and outside of the gun to prevent blockages and allow the gun to be reused.

For further information, see the dedicated section in the catalogue “TAPES, MEMBRANES, SEALANTS AND FIRE PROTECTION” available at www.rothoblaas.com

MEMBRANES AND TAPES | INSTALLATION OF TAPES, MEMBRANES AND FOAMS | 127

CONSTRUCTION DETAILS

CONSTRUCTION DETAILS Key construction details – such as base connections, doors and windows, water drainage, ventilation and service penetrations – require careful design. Every discontinuity is a potential weak point. The overall performance of the system depends on the quality of workmanship.

BASE CONNECTIONS: JUNCTION DESIGN

from page 130

WINDOW-TO-STRUCTURE JUNCTION

from page 140

VENTILATION IN ROOFS AND FAÇADES

from page 150

RAINWATER DRAINAGE AND DEFLECTION

from page 156

INTEGRATED DESIGN

from page 166

SERVICE PENETRATIONS AND FASTENING OF FAÇADE ELEMENTS

from page 168

The construction details shown in this chapter highlight the main issues and set out possible solutions. The guidance provided is not exhaustive and does not replace project-specific design. Each solution must be checked against the applicable national regulations, the construction system adopted, and the specific climatic and design conditions of the project.

CONSTRUCTION DETAILS | 129

BASE CONNECTIONS: JUNCTION DESIGN The base detail requires precision that both the design and working stages. The detail may vary depending on the architectural requirements, but the objective is always the same: to isolate the timber structure from ground moisture.

PROTECT WALL FROM CAPILLARY MOISTURE OUTDOOR

INDOOR COPLANAR CONCRETE KERB: CONNECT BAND NON-COPLANAR CONCRETE KERB:

PROTECT / GROUND BAND / PLASTER BAND OUT

PROTECT or START BAND + shrinkage-compensating fluid mortar

dimpled protection membrane

foundation waterproofing

Install a waterproof barrier between the timber and the concrete, preferably applied on the concrete base so that it does not compromise the breathability of the wall base. For slabs in contact with the ground, continuous waterproofing is required.

OUTDOOR

INDOOR COPLANAR CONCRETE KERB: CONNECT BAND

Rothoblaas tape

NON-COPLANAR CONCRETE KERB: PROTECT or START BAND + shrinkage-compensating fluid mortar

foundation waterproofing

Not only perimeter walls, but also internal walls must be separated from the concrete using a waterproof barrier and raised sufficiently in order to prevent rising damp.

130 | BASE CONNECTIONS: JUNCTION DESIGN | CONSTRUCTION DETAILS

AVOID DIRECT CONTACT WITH THE GROUND OUTDOOR

INTERNAL

timber wall raised above external and internal floor level

concrete kerb provide an adequate height differential(*)

finished floor level

floor level

draining layer to prevent standing water

The concrete kerb raises the support level of the timber structure above the finished external and internal floor levels, reducing the risk of standing water and moisture. This keeps the timber clear of the ground and limits possible damage caused by leaks from services or accidental wetting of indoor spaces. To ensure correct installation of the timber structure, the kerb must be constructed with a coplanar surface.

(*) The level difference must be sized according to the project context and local regulations.

OUTDOOR

ALU START

wall raised with UP LIFT and casting of the reinforced concrete kerb

geotextile fabric to protect the draining layer

provide an adequate height differential(*) corrugated drainage pipe foundation plate

In the absence of a concrete kerb, the detail requires careful design because the placing the wall below finished internal floor level increases the risk of accidental wetting. The junction must ensure sufficient distance from the drainage plane, permeable external paving and appropriate waterproofing in order to keep water away from the base of the timber wall. For critical situations, planned periodic inspection for seals, waterproofing and services are recommended.

CONSTRUCTION DETAILS | BASE CONNECTIONS: JUNCTION DESIGN | 131

AVOID INTERSTITIAL CONDENSATION OUTDOOR

INTERNAL

external wall insulation

Rothoblaas tape for airtightness

PROTECT or GROUND BAND for waterproofing + windtightness

finished floor level

continuous insulation below the timber wall external floor level

service penetration that does not come into contact with the timber wall and does not interrupt the insulation and waterproofing of the concrete kerb

In addition to waterproofing, ensure airtightness using self-adhesive products and reduce thermal bridges by ensuring the insulation continues over the outside face of the foundation to prevent the formation of cold spots.

OUTDOOR

INTERNAL

external wall insulation

COPLANAR CONCRETE KERB: CONNECT BAND

PROTECT or GROUND BAND for waterproofing + windtightness

NON-COPLANAR CONCRETE KERB: PROTECT or START BAND + shrinkage-compensating fluid mortar

shaped insulation to turn up the waterproofing and prevent standing water

If angle brackets or other fastening elements puncture the vapour control membrane, continuity of the airtight layer and vapour control layer must be restored.

132 | BASE CONNECTIONS: JUNCTION DESIGN | CONSTRUCTION DETAILS

PROTECT AGAINST RAIN SPLASHBACK AND FACILITATE DRAINAGE OUTDOOR

INTERNAL

insulation with drip profile

PLASTER BAND OUT / MULTI BAND

adequate height(*)

finished floor level 40 - 50 mm moisture-resistant insulation

drainage slope > 2%

Protect the wall with a butyl- or bitumen-based waterproofing layer; where the timber wall sits sufficiently above finished external ground level, an adhesive tape is sufficient, preferably breathable and suitable for plastering over. It is advisable to install a perimeter drainage strip to prevent standing water and splashback, ensure an internal/external level difference of 4–5 cm, and install paving with a minimum slope of 2%, with a greater fall at door thresholds.

OUTDOOR

INTERNAL

geotextile fabric to protect the draining layer

TRASPIR EVO adequate height(*)

PROTECT / GROUND BAND adequate height(*)

finished floor level 40 - 50 mm permeable paving to prevent standing water and splashback moisture-resistant insulation

drainage slope > 2%

(*) Dimensions must be determined according to the project context and local regulations.

ROTHOBLAAS RECOMMENDS PROTECT

START BAND

PLASTER BAND OUT

SELF-ADHESIVE BUTYL BAND, CAN BE PLASTERED

WATERPROOF PROFILE WITH HIGH MECHANICAL RESISTANCE

SPECIAL HIGH-ADHESION TAPE, CAN BE PLASTERED

CONSTRUCTION DETAILS | BASE CONNECTIONS: JUNCTION DESIGN | 133

CHOOSE THE CORRECT FASTENING SYSTEM To install the construction detail correctly, it is essential to consider the choice of fastening system from the outset, depending on the presence of the concrete kerb, wall alignment, and compliance with the required edge distances for timber and concrete. THREE-DIMENSIONAL ANGLE BRACKETS F1

Timber walls are generally fixed to a foundation using hold-downs, such as WHT or WKR, at the wall ends to resist tensile forces. Shear angle brackets such as TITAN or NINO are positioned at regular intervals and, as they are certified for loads in all directions, can replace hold-downs. TWO-DIMENSIONAL PLATES F1

Alternatively, use two-dimensional plates such as WHT PLATE C for tension or TITAN PLATE C for shear. In this case, particular care is needed when casting the concrete, which must be correctly aligned with the timber wall.

LEVEL TOLERANCE MANAGEMENT

reinforced concrete kerb

grout

gap

Place grout between the wall and the concrete to level the base. ETA-certified partial fastening layouts allow the nails or screws to be positioned higher in order to accommodate the mortar layer. WHT and WKR can be installed with a clearance gap to facilitate the installation of raised walls.

134 | BASE CONNECTIONS: JUNCTION DESIGN | CONSTRUCTION DETAILS

INTEGRATED SYSTEMS FOR BASE CONNECTIONS NON-RAISED BUILDING

RAISED BUILDING THE KERB IS CAST BEFORE WALL INSTALLATION

THE KERB IS CAST AFTER WALL INSTALLATION

ALU START

TITAN DIVE

UP LIFT

In the absence of a reinforced concrete kerb, Rothoblaas recommends using ALU START. The aluminium profiles allow accurate horizontal and vertical positioning before the installation of the timber walls. The aluminium also acts as a barrier against rising damp from the foundation.

Where a reinforced concrete kerb is present, Rothoblaas recommends TITAN DIVE. Corrugated pipes pre-installed in the kerb allow the installation of angle brackets and timber walls with generous horizontal and vertical tolerances. All base fastenings are made without the need for drilling anchors on site.

Where a reinforced concrete kerb is present, Rothoblaas recommends UP LIFT. The steel supports carry the weight of the building during installation, while the reinforced concrete kerb is cast afterwards, adapting to the position of the walls and giving the installer maximum flexibility during installation. In this case too, no on-site drilling is required for anchor installation.

A bond beyond the limit It is through our metal connectors that we make our way into building sites of traditional and hybrid, prefabricated and demountable timber constructions. The PLATES AND CONNECTORS FOR TIMBER, CONCRETE AND STEEL catalogue is now more up-to-date than ever. Products for every load range, complete design tables, precise solutions for different construction systems.

Download the catalogue and start designing with us rothoblaas.com

CONSTRUCTION DETAILS | BASE CONNECTIONS: JUNCTION DESIGN | 135

STRUCTURAL RESTORATION Where walls have been damaged by water ingress or moisture, UP LIFT can also be used to used when replacing the damaged lower section with a concrete kerb detail.

temporary support

Remove the external wall finishes to expose the damaged area and define the cutting line.

Carry out the work in sections. Cut the wall while temporarily supporting it with props to ensure the stability of the structure.

UP LIFT

PROTECT

Apply PROTECT to waterproof the timber wall and prevent rising damp.

Position UP LIFT and leve out any level irregularities using SHIM. Install the kerb reinforcement and insert starter bars between the kerb and the existing foundation.

Build the formwork for the kerb and cast the kerb using fluid shrinkage-compensated concrete.

Once the work is complete, the wall is supported by the new reinforced concrete kerb and is secured to the base using the UP LIFT supports. The external finishes can then be reinstated.

136 | BASE CONNECTIONS: JUNCTION DESIGN | CONSTRUCTION DETAILS

Greater acoustic comfort in your timber home. XYLOFON is the very high-performance resilient profile that ensures acoustic comfort in timber structures and houses. Made of a polyurethane compound, it is available in 6 versions, according to the load it must support. Tested and certified for use as a decoupling and mechanical interruption layer between structural elements, it reduces the transmission of airborne and structural noise (up to more than 15 dB). Rely on the best performing acoustic profile on the market.

Scan the QR code and find out more about the technical features of XYLOFON rothoblaas.com CONSTRUCTION DETAILS | BASE CONNECTIONS: JUNCTION DESIGN | 137

Timber structure raised by means of a kerb. Waterproof- Perimeter and internal timber walls raised on a concrete ing applied to the concrete base, with the wall aligned kerb, with the concrete kerb shaped at door openings. flush with the internal face with the internal face.

Timber wall raised on a kerb, with moisture-resistant insulation used at the base of the wall.

138 | BASE CONNECTIONS: JUNCTION DESIGN | CONSTRUCTION DETAILS

Butyl product protecting the wall applied discontinuous- Timber wall below the external finished level, no inly, and dimpled membrane penetrated by the anchor. sulation below the timber wall (thermal bridge risk) and inadequate waterproofing system.

Fastening plates incorrectly installed: failure to comply with edge distances or the presence of an uneven kerb, preventing correct insertion of screws and anchors and which may deform the connector plate.

CONSTRUCTION DETAILS | BASE CONNECTIONS: JUNCTION DESIGN | 139

WINDOW-TO-STRUCTURE JUNCTION DESIGN THE WINDOW JUNCTION The window-to-wall junction is one of the most sensitive points in the building envelope. This is where atmospheric, hygrothermal and mechanical stresses are concentrated: water and air can enter, and heat can escape. To ensure consistent performance and durability of the window, the detail must work as a single, continuous system, capable of draining water, sealing joints and maintaining insulation continuity.

LEVELS OF PROTECTION windtightness

thermalacoustic insulation

OUTDOOR

WHAT IT MUST WITHSTAND

airtightness

INTERNAL

WHAT IT MUST GUARANTEE

UV RAYS

ENERGY SAVING

HEAVY RAIN

HYGROTHERMAL PERFORMANCE

TEMPERATURE CHANGES

INDOOR COMFORT

WIND

ELASTIC RESPONSE

NOISE POLLUTION

AIRTIGHTNESS

FIRE

The details show how correct design of the three protection levels prevents water ingress and standing water. OUTDOOR

INTERNAL

140 | WINDOW-TO-STRUCTURE JUNCTION | CONSTRUCTION DETAILS

DETAILS TO CONSIDER WHEN DESIGNING WINDOW INSTALLATIONS

PRIMARY JOINT Connects the opening to the subframe or, where there is no subframe, to the fixed window frame. Transfers loads and provides continuous support: this is the element and ensures the stability of the entire window system.

PRIMARY JOINT

windows and doors

wall

SECONDARY JOINT AND SUBFRAME The subframe ensures correct alignment and flatness of the window, compliance with dimensional tolerances, and makes future replacement easier. The secondary joint connects the subframe and the window.

TIMBER-TO-TIMBER

TIMBER-TO-PVC

TIMBER-TO-METAL

Ensures consistency with the insulation build-up and reduces the risk of thermal bridges.

It provides good performance thanks to the low thermal conductivity of PVC and helps maintain insulation continuity.

Because of its high conductivity, metal creates linear thermal bridges and is not suitable where high thermal insulation performance is required.

CONSTRUCTION DETAILS | WINDOW-TO-STRUCTURE JUNCTION | 141

DESIGN CORRECTLY TO AVOID THERMAL BRIDGES Thermal bridges in the window-junction design are caused by discontinuous connections between the window, structure and insulation. Correct window design ensures continuity of the building envelope, reduces heat loss, prevents condensation and helps ensure high performance of the entire window system.

heat loss

SIMULATIONS UNDER EXTREME CONDITIONS USING A CERTIFIED CALCULATION METHOD In the window-to-wall junction, the most weak point from a thermal perspective are concentrated at the joint, with an internal temperature of +20 °C and an external temperature of −18 °C. Maintaining a window-edge internal surface temperature at the window edge of ≥ 12.6 °C, where mechanical ventilation with heat recovery (MVHR) is provided, prevents condensation and mould and maintain suitable hygrothermal conditions in the construction detail. Since the surface temperatures are close to the limit value (≈ 12.8 °C), the design of the junction becomes critical and must ensure continuity of the functional layers, including tapes and thin layers, to reduce the risk of thermal bridges.

external finish

-17.6 windows and doors -10.6

-3.6

subframe

3.4 12.8

12.8

17.4

weak point f(1)= 20°C θ(2)= 12,6°C Uw(3)= 0,19 W/m2K

internal finish

LEGEND: -18.0° -13.2° -8.3°

-3.5°

1.3°

6.1°

10.9°

15.8°

20.6° f= temperature factor on the internal surface θ= temperature at risk of surface condensation Uw= wall thermal transmittance

142 | WINDOW-TO-STRUCTURE JUNCTION | CONSTRUCTION DETAILS

DETAIL THE WINDOW SILL CORRECTLY The sill is the most exposed element of the lower window junction: here, any discontinuity can lead to water ingress, deterioration of the reveal, air leakage or a thermal bridge. For this reason, the detail must ensure continuity between the window and the façade, prevent standing water, and provide uninterrupted sealing and insulation.

40 mm

5°

MF1 expanding tape

minimum slope of 5° towards the outside

projection ≥ 40 mm beyond façade face

sill with drip groove

load-bearing structure

EXPAND BAND WINDOW BAND PLASTER BAND OUT

PROTECT

EXPAND BAND WINDOW BAND

SMART BAND

EXPAND BAND

1 3

STONE SILL PLASTER BAND OUT MULTI BAND WINDOW BAND

30 cm

PROTECT TERRA BAND UV SMART BAND

2 EXPAND BAND WINDOW BAND

BG1

EXPAND BAND

MF1

WINDOW BAND

EXPAND BAND WINDOW BAND

Incorrect sill detailing. Using multiple patches instead of a single continuous tape creates discontinuities and weak points.

Incorrect taping of the sub-sill and the corners of the window opening.

For further details, see "INSTALLATION OF TAPES, MEMBRANES AND FOAMS" on page 118

144 | WINDOW-TO-STRUCTURE JUNCTION | CONSTRUCTION DETAILS

SHEET METAL SILL PLASTER BAND OUT MULTI BAND WINDOW BAND

EXPAND BAND WINDOW BAND

30 cm

1 PROTECT

EXPAND BAND WINDOW BAND

side flashing

Incorrect welding of the sheet metal can create a path for water ingress if the sub-sill is not properly waterproofed, resulting in water ingress and longterm damage.

Correct sealing on the internal side: tape applied at the window-to-sill joint to ensure airtightness.

CONSTRUCTION DETAILS | WINDOW-TO-STRUCTURE JUNCTION | 145

DESIGN THE SHUTTER BOX The shutter box, another weak point in the window junction, must be designed as an integral part of the window-façade system. Continuity between the guide rail, reveal and integrated unit is essential for the correct integration of the three functional layers and for reducing water ingress and thermal bridging. Proper connection to the façade materials and provision allowing for effective drainage near the guide rails ensure long-term performance and the full performance of the building envelope.

LEGEND: windtight layer

airtight layer

WINDOW BAND EXPAND BAND

NAIL BAND GEMINI

BUILDING ENVELOPE MANAGEMENT

WEAK POINT Structural obstruction and thermal bridge risk

shading system

WEAK POINT Risk of water ingress and discontinuity in the building envelope

146 | WINDOW-TO-STRUCTURE JUNCTION | CONSTRUCTION DETAILS

ventilation

ROOF WINDOW

WEAK POINT Thermal bridge risk, ensure the three functional layers.

Roof window installed at a later stage: the membrane is cut to create the opening, resulting in an interrupted layer not connected to the window. This installation method fails to ensure membrane continuity or correct sealing of the junction.

Correct use of expanding tape to seal around the window perimeter: the material is installed continuously along the reveal, adapting to irregularities in the substrate and providing effective sealing against air and water.

ROOF SKYLIGHT SEALING - MEMBRANE & TAPES Scan the QR code and watch the video. SUBSCRIBE to our YOUTUBE channel and keep up to date on Rothoblaas products and news.

CONSTRUCTION DETAILS | WINDOW-TO-STRUCTURE JUNCTION | 147

Pay particular attention to the reveal: insulation and membranes, tapes and other thin functional layers must continue up to the top of the opening, minimising thermal bridging as much as possible.

WEAK POINT

SOLUTION WEAK POINT

Thermal bridge risk

Vapour barrier cut and left unconnected to the window. Unsealed voids between the frame and timber structure, with potential critical issues.

Window side detail: discontinuous insulation and irregular structural connections between timber, insulation and substrate, with a risk of air and water ingress and reduced thermal performance.

148 | WINDOW-TO-STRUCTURE JUNCTION | CONSTRUCTION DETAILS

ROTHOBLAAS RECOMMENDS FOR WINDOW SOUNDPROOFING, ALSO CONSIDER JOINT PERFORMANCE

WINDOW BAND SELF-EXPANDING SEALING TAPE FOR WINDOWS AND DOORS

MF1

Soundproofing of the gap: 10 mm Rs,w(ift) (C;Ctr) = 59 (-2;-3) dB

DID YOU KNOW THAT... Do all expanding tapes offer the same performance? intended use under the standard

resistance to heavy rain

permanent exposure

BG1

external-windtightness

≥ 600 Pa

yes

BG2

external-windtightness

≥ 300 Pa

internal-airtightness

MF1

multifunction-3 levels

≥ 600 Pa

yes

MF2

multifunction-3 levels

≥ 300 Pa

BGR

HERMETIC FOAM SOUNDPROOFING SEALING POLYURETHANE FOAM Soundproofing of the gap: 10 mm Rs,w(ift) (C;Ctr) = 63 (-1;-5) dB 20 mm Rs,w(ift) (C;Ctr)=62 (-1;-5) dB

MBS | MBZ SELF-TAPPING SCREW FOR MASONRY Tested by ift Rosenheim in accordance with MO-02/1 for pull-out, compression, pure shear and eccentric shear on calcareous substrates such as concrete and masonry. They ensure safe and durable fastenings in the primary joint, even under high-stress conditions.

K088198

CONSTRUCTION DETAILS | WINDOW-TO-STRUCTURE JUNCTION | 149

VENTILATION IN ROOFS AND FAÇADES Upon completion of construction, buildings often contain high levels of moisture and possible standing water due to construction processes that introduce moisture into some layers and materials. Therefore, the building must be designed to promote the dissipation and drying of the hygrothermal load. Ventilation plays a key role in expelling moisture over time, including in the event of leaks or standing water caused by other events during the building’s service life.

PROVIDE ADEQUATE VENTILATION

MOISTURE MANAGEMENT Good ventilation helps moisture dry out within the building envelope within the building envelope, helping prevent interstitial condensation in the insulation and structure. It also helps dry out water ingress and vapour passing through the layers, reducing the risk of mould and decay.

ADDITIONAL PROTECTION The ventilation layer provides additional protection in the event of accidental water ingress. It creates a second drainage level and prevents standing water. The possibility of drying reduces biological degradation and maintenance requirements, increasing the durability of the structure and materials.

See further details under “RAINWATER DRAINAGE AND DEFLECTION” on page 156 See further details under “WINDTIGHT MEMBRANES“ on page 106

150 | VENTILATION IN ROOFS AND FAÇADES | CONSTRUCTION DETAILS

MATERIAL DURABILITY Ventilation helps dissipate theheat that builds up beneath sun-exposed layers to solar radiation and lowers the operating temperatures of insulation, membranes, tapes and building materials in general, limiting ageing caused by thermal stress.

IN WINTER Ventilation allows any snow accumulated on the roof to melt evenly.

IN SUMMER Ventilation helpsdissipate the heat that builds up beneath the outer layer, improving indoor comfort. The airflow reduces the heat accumulated by the cladding and allows the insulation layer to work under smaller temperature differences, reducing cooling demand.

ON SITE MEASUREMENTS 19,2°C

External air temperature

21,0°C

Internal wall temperature

27,0°C

HPL panel temperature

CONSTRUCTION DETAILS | VENTILATION IN ROOFS AND FAÇADES | 151

ROOF AND FAÇADE VENTILATION DETAIL

2 3 1

2 3 5 4

152 | VENTILATION IN ROOFS AND FAÇADES | CONSTRUCTION DETAILS

VENTILATION OPENINGS Ventilation openings must be unobstructed and protected (insect mesh, grilles). For maintenance, provide access to inspect and clean of the air inlets. This ensures continuous ventilation without the need for active components or parts prone to deterioration.

CONTINUOUS AIRFLOW PATH Avoid obstructions at window sills, chimneys, windows, doors, roof windows and corners. Where necessary, interrupt the battens or create openings so that air can pass through. Use vertical battens on façades wherever possible.

AIRTIGHT LAYER The airtight layer (membranes, plaster, panels or taping) must be sealed and intact to ensure windtightness and watertightness, and to promote drainage without creating pockets or areas of standing water.

3 VENTILATION CAVITY Design the thickness of the ventilation cavity carefully, particularly in façades and flat roofs. In general, the cavity is usually a few centimetres deep, depending on the pitch and length of the roof slope or façade. Pitched roofs: 4–6 cm (more for long roof slopes) Ventilated façades: 2–5 cm (always check any applicable regulations or specific project requirements, including hygrothermal performance)

COMPATIBILITY AND THERMAL RESISTANCE Check the compatibility of materials and their resistance to heat and UV rays, especially where the cladding is not perfectly sealed and has small gaps or discontinuities. Choosing the right products is essential to protect the insulation layer and structure.

5 ROTHOBLAAS RECOMMENDS

AIRTIGHTNESS AND WATERPROOFING

PASSIVE FIRE PROTECTION

SEALANTS, FOAMS AND LIQUID MEMBRANES

ROOF AND VENTILATION ELEMENTS

For further information, see the catalogue TAPES, MEMBRANES, SEALANTS AND FIRE PROTECTION.

CONSTRUCTION DETAILS | VENTILATION IN ROOFS AND FAÇADES | 153

Obstruction of the ventilation cavity by foam, tape or unprotected insulation.

Discontinuous air inlets, with insufficient or interrupted inlet and outlet openings, for example at doors and windows, corners and chimneys.

Details that do not drain retain water, such as window sills and horizontal joints.

Clean and unobstructed ventilation cavity to promote airflow.

Continuous ventilation openings, free from debris or residue.

Drainage system at facade breaks/ discontinuities.

Ventilation cavities without proper design or correct installation can be harmful, creating trapping warm air and increasing the risk of condensation prone to condensation.

154 | VENTILATION IN ROOFS AND FAÇADES | CONSTRUCTION DETAILS

FLAT ROOF

AIR INLETS Air inlets should preferably be face the prevailing wind and arranged with a slight difference in height between the inlet and outlet openings.

VENTILATION AND WATERPROOFING Use dedicated accessories for the ventilation of flat roofs and terraces that ensure both ventilation and watertightness.

SOLAR RADIATION Different levels of solar exposure across different areas of the roof (e.g. existing buildings, trees, photovoltaic or solar roofs) promotes ventilation, as it creates air at different temperatures within the ventilated cavity, triggering convective airflow.

3 CONSTRUCTION DETAILS | VENTILATION IN ROOFS AND FAÇADES | 155

RAINWATER DRAINAGE AND DEFLECTION STANDARD BUILDINGS When designing timber buildings, the designer must ensure correct water drainage along the full height of the building, considering the route from the highest point down to the base connection. No areas or details should allow water to stand. For proper rainwater drainage, buildings should be designed with projecting eaves and projecting elements, with floors and roof surfaces falling outwards. Avoid layouts that direct water back towards the building.

roofs and floor structures sloping outwards, not converging towards the building

GUTTER exposed gutter

buildings designed with roofs featuring projecting eaves

DOWNPIPES exposed downpipes

BASE CONNECTION see dedicated section on page 130

156 | RAINWATER DRAINAGE AND DEFLECTION | CONSTRUCTION DETAILS

COMPLEX BUILDINGS The use of concealed downpipes and gutters is not recommended, as they make maintenance and cleaning difficult. Buildings with flat roofs, converging roof slopes and exposed timber elements require specific detailing, covered in the dedicated sections.

WATERPROOFING terraces and flat roofs

eaves gutter concealed gutter

base connection at terrace and balcony level

TIMBER COLUMN BASE CONNECTIONS

BASE CONNECTIONS see dedicated section on page 130

CONSTRUCTION DETAILS | RAINWATER DRAINAGE AND DEFLECTION | 157

GUTTER The use of eaves without an overhang with concealed gutters and downpipes is not recommended. Concealed rainwater drainage systems increases the risk of decay, especially where maintenance is poor or there are design or installation errors. The concealed-gutter detail can also be adapted for gutters between adjacent buildings by mirroring the arrangement EXPOSED GUTTER Install the sheet-metal gutter so that it remains exposed, to facilitate maintenance easier and the blockages easy to identify.

bird guard mesh

MONOLITHIC BREATHABLE MEMBRANE load-bearing structure and insulation (variable)

exposed gutter

Whatever type of gutter is selected, regular maintenance is required. Increasingly, partly as a result of climate change and heavier rainfall, gutters are undersized, which can lead to decay in timber structures.

CONCEALED GUTTER The construction of a concealed gutter requires specific design to ensure effective rainwater drainage and provides suitable technical solutions to prevent possible blockages. bird guard mesh overflow outlet

MONOLITHIC BREATHABLE MEMBRANE

drainage sump load-bearing structure and insulation (variable)

the waterproofing membrane must extend at least 10 cm above the maximum height of the upstand

sloped water drainage channel

Note: Do not create the outlet connection in the sump using a simple folded sheet-metal piece sealed with silicone. Use purpose-made components, such as L-shaped performed outlets, made from the same material as the waterproofing membrane and complete with overflow. Note: Where there is a risk of snow accumulation, provide heating cables.

158 | RAINWATER DRAINAGE AND DEFLECTION | CONSTRUCTION DETAILS

DOWNPIPES The number and location of downpipes must be defined at the design stage, before work begins on site. UNI 12056-3 may be used to size and position downpipes. The standard applies to both pitched roofs and flat roofs and terraces.

The standard does not prescribe a fixed number of downpipes, but requires calculation of:

Sf = 100m2

• drainage area Sf • design rainfall intensity • run-off coefficient • flow rate to be drained Q • minimum diameter based on water velocity • pressure loss verification As a general guide, one Ø10 downpipe is considered for every 70–100 m² of roof area, and 1 downpipe every 15–25 m of gutter. For pitched roofs, the gutter is normally installed with a slope of 0.2–0.3%, whereas for flat roofs and terraces the rainwater drainage system must be designed specifically for the project. Increasingly, partly as a result of climate change and heavier rainfall, gutters are undersized, which can lead to decay in timber structures.

ROTHOBLAAS RECOMMENDS

RAIN TUBE TEMPORARY DOWNPIPE FOR CONSTRUCTION PHASES

It protects building façades during construction or renovation work Versatile, easy-to-use solution Can be used until the permanent downpipes are installed

CONSTRUCTION DETAILS | RAINWATER DRAINAGE AND DEFLECTION | 159

TEMPORARY ON-SITE WATERPROOFING FOR FLAT ROOFS AND TERRACES Temporary waterproofing ensures temporary protection of the roof layers during installation of the roof build-up. The system must ensure watertightness, compatibility with subsequent layers and resistance to site conditions until the final waterproofing layer is installed.

detail A

detail B

finished floor level

300 mm

Performed outlet to be sealed before completion of the build-up

BYTUM BASE 2500

DEFA 200 DEFA TRASPIR

load-bearing structure and insulation (design variables)

The illustrated example intentionally represents the most critical case, so as to be effective even in less demanding situations. For flat timber roofs, it is preferable to use a load-bearing structure with exposed joists and decking, designed with a minimum slope of 2% for all functional layers, as indicated by certain standards (e.g. ÖNORM B 3691), in order to reduce the risk of standing water and water ingress even if the roof covering is incorrectly installed. Under these conditions, BARRIER ALU NET ADHESIVE 300 can be used both as temporary protection and as a vapour barrier. Particular attention must be paid to CLT railings, which are particularly sensitive to standing water, and for which waterproofing and drainage details must be carefully designed. The integration of monitoring systems, such as moisture sensors, is also recommended to detect water ingress promptly and prevent structural damage.

160 | RAINWATER DRAINAGE AND DEFLECTION | CONSTRUCTION DETAILS

BYTUM BASE 2500

min. 20 cm

1 Install a temporary bituminous membrane (BYTUM BASE 2500 or GROUND BAND), laid parallel to the side of the building and turned up the wall for at least 30 cm above the finished external floor level. At right-angled corners, always provide an XPS or timber fillet.

2 To allow water to drain during temporary waterproofing, provide L-shaped performed drainage outlets made from the same material as the temporary membrane.

ROTHOBLAAS RECOMMENDS GROUND BAND SELF-ADHESIVE BITUMINOUS MEMBRANE

SELF-ADHESIVE BITUMINOUS MEMBRANE

Temporary on-site waterproofing installed correctly.

CONSTRUCTION DETAILS | RAINWATER DRAINAGE AND DEFLECTION | 161

FINAL WATERPROOFING FOR FLAT ROOFS AND TERRACES Final waterproofing ensures the long-term watertightness of the roof. The system must guarantee continuity, mechanical strength and durability, protecting the underlying layers and ensuring effective rainwater drainage in accordance with the project specifications.

A B

detail A

detail B sheet metal skirting

100 mm

BYTUM BASE 2500+ BYTUM SLATE 3500

sheet metal skirting

drainage sump

overflow

BYTUM BASE 2500 DEFA 200 DEFA TRASPIR tapered insulation

load-bearing structure and insulation (variable) exposed downpipe for ease of maintenance

The design of rainwater drainage for flat roofs and terraces follows the same methodology. The roof area must be calculated and identify suitable points for the installation of downpipes, collection sumps and overflows, ensuring proper rainwater drainage in accordance with the project specifications.

162 | RAINWATER DRAINAGE AND DEFLECTION | CONSTRUCTION DETAILS

BYTUM SLATE 3500 BYTUM BASE 2500

3-4%

BYTUM SLATE 3500 SELF-ADHESIVE SLATED BITUMINOUS MEMBRANE

BYTUM BASE 2500

Where necessary, provide an insulation build-up above the temporary membrane using pre-shaped insulation with a 3–4% slope.

Complete the waterproofing with a bituminous membrane (BYTUM BASE 2500 + BYTUM SLATE 3500) or an EPDM or PVC membrane.

SELF-ADHESIVE BITUMINOUS MEMBRANE

BYTUM SLATE 3500

BYTUM BASE 2500

ROTHOBLAAS RECOMMENDS

Complete the drainage outlets with L-shaped performed outlets, made from the same material as the membrane and fitted with an overflow. Note: Do not create the outlet connection in the sump using a simple folded sheet-metal piece sealed with silicone. Use purpose-made components, such as L-shaped performed outlets, made from the same material as the waterproofing membrane and fitted with an overflow. Note: BYTUM BASE 2500 + BYTUM SLATE 3500 is a suitable solution for terraces and non-accessible roofs, or roofs with raised flooring.

Keep drainage channels free of gravel to allow unobstructed rainwater run-off.

CONSTRUCTION DETAILS | RAINWATER DRAINAGE AND DEFLECTION | 163

COLUMN BASE CONNECTION Timber elements such as columns, whether in contact at ground level or on terraces, must always be raised at least 10 cm above the finished external floor level.

BYTUM BASE 2500+ BYTUM SLATE 3500

Performed outlet in bitumen or in the same material as the membrane

BLACK BAND

BYTUM BASE 2500

BYTUM BASE 2500 GROUND BAND

BLACK BAND

Where fastenings pass through the waterproofing membrane, use preformed outlets in the same material as the membrane to reinstate the waterproofing layer.

Performed outlet

DEFA 200 DEFA TRASPIR

BYTUM BASE 2500

BYTUM SLATE 3500

The use of silicone instead of performed outlets is not recommended.

164 | RAINWATER DRAINAGE AND DEFLECTION | CONSTRUCTION DETAILS

Firestop penetrations in timber structures The most suitable passive fire protection for service penetrations depends on the installation context.

Download the full brochure rothoblaas.com

INTEGRATED DESIGN Moisture management directly affects the durability and performance of timber structures. An integrated approach makes it possible to protect the structure and ensure long-term durability and performance.

PROTECTION OF TIMBER STRUCTURES LEGEND: critical areas

300 mm

• Pay particular attention to areas most exposed to moisture, such as bathrooms, kitchens, laundries and rooms served by water systems. • Identification of critical areas and use of waterproof membranes. Complete systems or liquid sheaths may be used in combination with cement-based glues and plastic adhesives. • Provide a concealed primary waterproofing layer between the edge of the sanitary fitting and the wall finish (elastic two-component cementitious membrane), and a visible secondary waterproofing layer using suitable sealants (water-repellent grout or silicone) around sanitary fittings and sinks. • Use suitable cladding: avoid standard plasterboard and opt for fibre cement or other materials resistant to moisture and condensation. For further design guidance, refer to DIN 18534.

As a general rule, continuous waterproofing should be applied to the entire wall behind ceramic tile finishes. Avoid configurations where a bathtub is used as a shower and solutions with flush shower trays.

Water systems must be installed in a service wall, avoiding runs within the timber load-bearing structure. If the available space is insufficient, the service wall must be increased in depth, without cutting grooves into the timber, and provision must be made for temporary end caps to extend beyond the tiled finish layer. These are temporary components, subject to movement and not suitable for ensuring watertightness.

166 | INTEGRATED DESIGN | CONSTRUCTION DETAILS

SERVICES MANAGEMENT

Grouped services within ducts and/or accessible service routes to facilitate maintenance of the entire building services system and inspection of pipes and air ducts.

Install within service walls or suspended ceilings, avoiding runs within the timber load-bearing structure.

Carry out regular maintenance of drain traps to prevent the progressive build-up of residue (grease, soap, hair, etc.), which reduce the effective pipe section, compromise drainage capacity and increase the risk of standing water and backflow, with negative effects on system durability and on the frequency of emergency interventions.

It is recommended to use components from the same building services system to ensure compatibility and correct functioning.

To avoid the risk of condensation, cold water pipes must be properly insulated along their entire route, ensuring continuity of insulation. During construction, their integrity must be preserved, avoiding damage that could compromise performance.

CONSTRUCTION DETAILS | INTEGRATED DESIGN | 167

SERVICE PENETRATIONS AND FASTENING OF FAÇADE ELEMENTS

4 3 1 2

5 6

7 168 | SERVICE PENETRATIONS AND FASTENING OF FAÇADE ELEMENTS | CONSTRUCTION DETAILS

When the windtight and airtight envelope is interrupted by service penetrations in the roof or façade, the sealing must be reinstated using specific products. The same methods apply to both airtightness and wind tightness.

sealing of bathroom vent pipes MANICA FLEX + FLEXI BAND, MANICA PLASTER, WELDING PIPE

sealing of extractor hood vent pipe MANICA FLEX + FLEXI BAND, MANICA PLASTER, WELDING PIPE

sealing of antenna pipe on the membrane MANICA PLASTER, FLEXI BAND, MANICA FLEX + FLEXI BAND, MANICA, WELDING PIPE

sealing of antenna pipe on the roof covering

sealing of photovoltaic panel pipes:

MANICA POST, MANICA LEAD

MANICA PLASTER, MANICA FLEX + FLEXI BAND

sealing of power supply penetrations for electric mechanical shutters on the internal airtight side: MANICA PLASTER, MANICA FLEX + FLEXI BAND, TUBE STOPPER, BLACK BAND

FASTENING LIGHTWEIGHT FAÇADE ELEMENTS

At the design stage, incorporate high-density non-structural insulating elements into the external insulation system to prevent deformation under load. Use gaskets to ensure correct sealing of the opening.

FASTENING HEAVY AND STRUCTURAL FAÇADE ELEMENTS Install high-density structural insulation inserts within the external wall insulation layer. For the fixing of external components to the insulation system, use connectors fitted with sealing gaskets to ensure proper sealing of the penetration point.

CONSTRUCTION DETAILS | SERVICE PENETRATIONS AND FASTENING OF FAÇADE ELEMENTS | 169

ROTHOBLAAS RECOMMENDS

FLEXI BAND UNIVERSAL SINGLE-SIDED HIGH-ADHESION TAPE

Chemical sealing.

Hot-air sealing.

Tape sealing.

MANICA FLEX SEALING SLEEVE FOR CONDUIT AND CABLE PASSAGE

MANICA PLASTER ADHESIVE SEALING SLEEVE THAT CAN BE PLASTERED

BLACK BAND UNIVERSAL SINGLE-SIDED BUTYL TAPE

WELDING PIPE SLEEVE

Chemical sealing.

Hot-air sealing.

170 | SERVICE PENETRATIONS AND FASTENING OF FAÇADE ELEMENTS | CONSTRUCTION DETAILS

ROTHOBLAAS RECOMMENDS

MANICA POST

MANICA LEAD

ADHESIVE SEALING SLEEVE FOR OUTDOORS

LEAD PROFILE WITH EPDM SLEEVE

MANICA

TUBE STOPPER

SEALING SLEEVE WITH SHRINK TUBING AND CLAMP

CABLE SEALING PLUGS

Thanks to partnerships with universities, research centres and specialised companies worldwide, Rothoblaas courses bring speakers with practical experience and proven expertise in technical consultancy into the classroom. The training combines theoretical knowledge with practical application and is aimed at engineers, architects, carpenters, safety specialists and other professionals in the construction sector. ROTHOSCHOOL ON TOUR We bring training directly to local areas, with hands-on sessions for industry professionals.

Find the course that suits you! rothoblaas.com

CONSTRUCTION DETAILS | SERVICE PENETRATIONS AND FASTENING OF FAÇADE ELEMENTS | 171

CONSTRUCTION PROJECT EXECUTION PLANS

CONSTRUCTION PROJECT EXECUTION PLANS The transport, storage, assembly and moisture management stages are defined through construction project execution and control plans that address common critical issues: safety, performance, durability and overall build quality. The moisture management plan does not overlap with the others, but instead runs through them, influencing timing, detailing and control procedures at every stage of operation.

CONSTRUCTION PROJECT EXECUTION PLANS

from page 175

MOISTURE MANAGEMENT PLAN

from page 176

TRANSPORT AND LIFTING PLAN

from page 180

STORAGE PLAN

from page 184

ASSEMBLY PLAN

from page 186

SAFETY PLAN

from page 192

CONSTRUCTION PROJECT EXECUTION PLANS | 173

ON-SITE MATERIAL MANAGEMENT PLANS Logistics management on timber construction sites plays a decisive role, as it speeds up project execution. Through sequenced deliveries, reduced storage and limited intermediate handling, idle time on-site and exposure and exposure to external agents are reduced.

reinforced concrete

steel

timber

long curing times

speed

°C

weather resistance

sensitivity to temperature variations

sensitivity to moisture

high environmental impact

low environmental impact

The primary regional-scale reference having an explicit regulatory role in these aspects is now Eurocode 5 Part 3 (Fpr EN 1995-3:2025), which links design and project execution through the construction specification. The document transfers the requirements defined at the design stage to the contractor and provides guidance for supervision and inspection, introducing minimum requirements for fabrication, assembly and installation, including moisture control during project execution, protection details, execution quality and geometric deviations. This regulatory framework highlights the decisive role of the project execution stage in ensuring the safety, durability and final quality of the works.

174 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

CONSTRUCTION PROJECT EXECUTION PLANS CONSTRUCTION PROJECT EXECUTION PLANS

TRANSPORT AND LIFTING PLAN

STORAGE PLAN MOISTURE MANAGEMENT PLAN ASSEMBLY PLAN

Transport, storage, assembly and moisture management are temporary conditions that affect the safety, performance, durability, cost and quality of the building. Water is a cross-cutting factor, which is why moisture management is integrated into all the other plans.

CONSTRUCTION PROJECT EXECUTION PLANS

INSTALLATION

TRANSPORT AND LIFTING PLAN INSPECTION MOISTURE MANAGEMENT PLAN MONITORING

STORAGE PLAN

ASSEMBLY PLAN

Installation, inspection and monitoring are activities that cut across all stages of construction and are essential for the implementation, verification, and effective control of the of the various construction project execution plans. These aspects are explored in greater detail from page 46 “INSTALLATION AND INSPECTION OF FASTENING SYSTEMS”.

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 175

MOISTURE MANAGEMENT PLAN The moisture management plan is intended to prevent damage to the structure caused by moisture variations during manufacturing, transport, storage, assembly and in-situ drying.

CONSTRUCTION PROJECT EXECUTION PLANS

TRANSPORT AND LIFTING PLAN

It is not a standalone plan, but a cross-cutting one, as it influences the timing, details and checks relating to transport, storage and assembly.

STORAGE PLAN

MOISTURE MANAGEMENT PLAN

ASSEMBLY PLAN

The plan must define: • the moisture content limit, or the acceptable range, at the various stages • the conditions required to limit swelling, shrinkage, excessive deformation or deterioration of the timber and connections • the measures to limit moisture absorption not compatible with the service conditions • the methods for checking, monitoring and managing deviations from the established limits.

REFERENCE MOISTURE CONTENT VALUES BY ELEMENT TYPE BY TIMBER TYPE in service

in service

types

upon delivery to site

solid softwood

< 20%

8 - 13%

glulam

about 12% ± 3%

6 - 10%

9 - 13%

LVL

about 10% ± 2%

6 - 10%

10 - 16%

CLT

about 12% ± 2 - 3%

6 - 12%

9 - 15%

SC1

SC2

SC3

SC1 SC4

SC2

8 - 13%

GENERAL VALUES FOR EACH STAGE condition

reference value

sawn timber

may exceed 100%

timber dried for engineered timber products

12% ± 3%

acceptable for enclosure / roofing

<15%

balanced moisture content in service

6 - 8%

risk of fungal growth

26 - 60%

SOURCE: adapted from the 2025 International Mass Timber Report

176 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

SC3

SC4

TEMPORARY SUPPORT STRUCTURES The plan also establishes who measures, where measurements are taken, how measurements are taken and how the results are recorded. Inspections must be carried out at representative points and in the areas at greatest risk, avoiding measurements taken on free water or standing surface water, as these would alter the result. The plan must also establish which data are to be recorded at each inspection; at a minimum, the following shall be included: • weather conditions • the condition of the storage area • the effectiveness of temporary protection • the presence of standing water • any corrective actions taken For each structural element, the measurement points and reading methods must be defined.

measurement area

300 mm 300 mm

300 mm

critical measurement area

Example of measurement area for CLT wall panels.

measurement area

Example of measurement area for CLT floor panels.

measurement area

Example of measurement area for beams and columns.

MEASURE THE TIMBER MOISTURE CONTENT When measuring timber moisture content, if electrical moisture meters are used, it is recommended to use EN 13183-2:2022 as the reference standard. The method and frequency must be defined and scheduled at the most significant stages of the construction process:

0.3 x width of element

• at delivery • during storage • during assembly • and upon enclosure of the works.

300 mm from the end 0.3 x thickness of element SOURCE: The Swedish Forest Industries Federation, 2026.

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 177

MOISTURE MANAGEMENT PLAN WORKFLOW

PLANNING STEP 1

STEP 2

STEP 3

DEFINE LIMIT VALUES AND ACCEPTABLE RANGE

IDENTIFY THE RISKS

MEASUREMENTS, MONITORING ROLES AND RESPONSIBILITIES

• moisture content for manufacturing, assembly and service • different values for materials or parts of the works • permitted moisture content at installation • permitted moisture content before enclosure • need for controlled drying

• wetting • standing water and pooling • swelling, shrinkage, deformation, deterioration

• how, where and when to measure • how to record and assess the results • inspection of the correct installation of tapes, membranes and foams • who measures, who checks • who authorises continuation • who decides on corrective actions

See further details on page 34

See further details on page 176

and subsequently

See further details on page 118

DEFINE THE PROTECTION MEASURES

• during transport • during storage • during assembly

See further details on page 82

178 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

MARGIN STEP 4

STEP 5

STEP 6

MEASURE THE AMBIENT CONDITIONS

DEFINE THE CORRECTIVE ACTIONS

CHECK BEFORE ENCLOSURE

• when to record temperature and relative humidity • how to correlate these measurements with moisture content values • when to integrate site data with local weather data

• suspension of works • restoration of protection measures • water drainage and removal • controlled drying • review of the sequence or enclosure

See further details on page 18

See further details on page 156

• moisture content • absence of free water • effectiveness of protection measures and drainage • compliance with the plan limits

See further details on page 176

define for the project and for critical elements

PLAN OUTPUT

Moisture limit values and acceptable ranges Risk of wetting and standing water Protection measures planned for each step

Methods, timing and responsibility for measurements Corrective actions in the event of deviations Pre-enclosure checks

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 179

TRANSPORT AND LIFTING PLAN The transport plan is the first point of control during project execution. It concerns not only delivery to site, but also the preservation of the integrity and performance of the elements. At this stage, it is important to distinguish between two related aspects: lifting, concerning attachment, handling and positioning, and transport, concerning restraint, protection and delivery up to the point of installation.

LIFTING

For structural elements, lifting requires a specific assessment of temporary loads and the lifting system. An element correctly designed for its final configuration may be damaged if lifted at inappropriate points, using devices that are not compatible with the geometry of the element, or using procedures that do not comply that do not comply with the operating instructions. In the worst-case scenario, such an error may result in damage to the element and site accidents related to loss of stability or detachment of the load. See further details on page 182.

TRANSPORT Transport concerns the restraint and protection of the element on the vehicle until delivery. Avoid displacement, damage to edges, damage to membranes and already-applied details, corrosion of pre-installed fastenings and, more generally, conditions that may compromise the quality of the element before installation.

land transport (short and medium haul)

land or sea transport (long haul)

Use of straps to secure the panels to the vehicle dur- Additional protection of the panels in the case of long ing transport. journeys or possible exposure to corrosive agents.

180 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

The transport plan must ensure two outcomes: the preservation of the functional and aesthetic requirements of the materials during transfer, and the coordination of delivery with assembly, so as to minimise onsite storage. Where possible, the most effective solution is just-in-time delivery, with immediate installation or installation shortly after unloading.

77 44

CLIENT: XXX BUILDING SITE: XXX

NR.

CLT PANEL - 100 mm ( 20 + 20 +20 + 20 +20) 104.5 cm x 164.0 cm - NR.8 DATE: XXXXX

CLIENT: XXX BUILDING SITE: XXX

NR.

CLT PANEL - 100 mm ( 20 + 20 +20 + 20 +20) 104.5 cm x 164.0 cm - NR.8 DATE: XXXXX

CLIENT: XXX BUILDING SITE: XXX

NR.

CLT PANEL - 100 mm ( 20 + 20 +20 + 20 +20) 104.5 cm x 164.0 cm - NR.8 DATE: XXXXX

CLIENT: XXX BUILDING SITE: XXX

NR.

Arrangement of panels during transport to facilitate their lifting and assembly. CLT PANEL - 100 mm ( 20 + 20 +20 + 20 +20) 104.5 cm x 164.0 cm - NR.8 DATE: XXXXX

The panels must be numbered according to the installation sequence and positioned during loading so as to allow unloading and installation in the planned order.

ROTHOBLAAS RECOMMENDS

RATTLE

PHYTHON

FASTENING STRAP WITH TENSIONER

RING-SHAPED ANCHOR BELT

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 181

LIFTING PLAN WORKFLOW

STEP 1

STEP 2

STEP 3

PROJECT INPUT

LOAD ANALYSIS AND LIFTING POINTS

SELECTION OF THE LIFTING SYSTEM

based on based on the structural design

Identify each element to be handled and define:

• load • geometry • lifting method • architectural finish • transport and installation requirements

• identify the centre of gravity and the anchor points • verify the strength of the connections during lifting

• mass / load to be lifted • geometry and dimensions • lifting orientation • visible faces / non-visible faces • installation conditions

SCREWED / MECHANICALLY FASTENED DEVICES

STRAP / TEXTILE DEVICES

WASP

DRAGON

RAPTOR MINI

OCTOPUS

RAPTOR

VIPER

RAPTOR MAXI

MANTIS

R’WLL RWLL

128

0k g

For further information, see the catalogue “TOOLS FOR TIMBER CONSTRUCTION”

182 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

STEP 4

STEP 5

SIZING OF THE LIFTING DEVICE

INSTRUCTIONS FOR USE

before use

in accordance with the applicable standards

• verify the load capacity of each lifting device, taking into account the type and number of fastenings and the lifting angle. • verify the need for spreader beams to ensure load balance

• correct positioning of the device • correct installation of the fastenings • required tightening torque • minimum distance from the edge

after use

REUSE INSTRUCTIONS

R’WLL β

R’WLL

β RWLL

final check

INSTALLATION OF THE SYSTEM ACCORDING TO THE MANUALS

DISPOSAL DIRECTIONS

RWLL

LIFTING PLAN OUTPUT

Code / element identification Weight Lifting points Selected device Category: screwed / mechanical or textile / strap Category: singleuse / multiple-use Verify requirements Reference manual Architectural notes Lifting and installation sequence

• DEVICE: refer to the manual • FASTENING: possible only when used with VGS PLATE

VGS PLATE REUSE GUIDELINES

The reuse guidelines are available at www.rothoblaas.com

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 183

STORAGE PLAN The plan is activated when there is a time interval between delivery and installation. Each material has specific requirements, but, in general, proper storage is based on two principles or forms of protection: • from below: separation from the ground • from above: top protection

separation from the ground

top protection

TIMBER AND TIMBER-BASED STRUCTURAL MATERIALS Store according to the assembly sequence, without obstructing unloading, handling and installation.

METALWARE AND FASTENINGS Store protected from salts and corrosive agents, particularly in environments exposed to marine aerosol.

INSULATION

TAPES

Avoid compression caused by stacking, especially for soft insulation materials.

Store in the original packaging in a dry, covered location, with particular attention to butyl tapes. Protect from UV exposure.

MEMBRANES

ADHESIVES, RESINS, SEALANTS

Store on pallets, avoiding contact with the ground, UV exposure and high temperatures, with particular attention to adhesive and bituminous membranes.

Store in a dry, covered location, maintaining the temperature specified in the technical data sheet.

For each product, always refer to the technical data sheet and, where available, the instruction manual, to ensure correct storage, durability and performance. For further details, also consult the catalogues. Use a lockable container to protect tools and machinery from weather and theft.

184 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

STORAGE PLAN WORKFLOW For each material, the storage plan must define:

STEP 1

STEP 2

STEP 3

STORAGE POSITION

SEPARATION FROM THE GROUND

TOP PROTECTION

To ensure protection from below, against splashes and rising damp.

To limit exposure to rain and weather, and to ensure ventilation.

According to the assembly sequence and temperature requirements.

CONTAINER

CAP ECO

PORTABLE STORAGE FOR THE WORKSITE

TARPAULIN FOR ROOFS

CAP PLUS Lockable CONTAINER access.

TARPAULIN FOR ROOFS to restrict

RBBOX CONTAINER For each material, indicate

STORAGE PLAN OUTPUT

Where it is placed, according to the assembly sequence How it is supported, to ensure protection from below How it is protected from above, against water and weather exposure

What specific conditions it requires What checks must be carried out before installation

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 185

ASSEMBLY PLAN The assembly plan governs the transition from a sequence of individual elements to a load-bearing system that is not yet complete. It is not enough for the finished building to be correct; each intermediate stage must also be kept under control, not only for the durability of the finished building, but also for site safety.

ASSEMBLY SEQUENCE The assembly sequence must be consistent with the structural design, which governs the entire project execution process; the assembly methods must be compatible with its underlying assumptions. At this stage, load paths are checked and temporary configurations, provisional loads and intermediate installation steps are verified, avoiding risks to both the structure and the safety of workers on site.

7 4

9 6

static configuration

assembly order

temporary support structures

ROTHOBLAAS RECOMMENDS GIRAFFE ASSEMBLY SUPPORT

186 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

TEMPORARY SUPPORT STRUCTURES Props, bracing, temporary supports and retaining devices, including fall-arrest systems and collective protection measures, are not merely site accessories, but necessary conditions for assembly. They must be consistent with the structural design, verified for the actual conditions of use, and made up of certified systems. Without adequate temporary supports and collective protection measures, the minimum conditions for safe assembly do not exist.

CHECKING TEMPORARY SUPPORTS ON SITE

Checking the support using GIRAFFE CALCULATOR.

Positioning of the head plate on the upper third (as BRACING) or on the bottom of the panel (as a PROP).

Checking the correct angle and fastening of the base plate.

GIRAFFE as a PROP.

Adjustment and levelling using the handle.

5 After fastening the wall, disassemble the GIRAFFE supports and prepare them for reuse.

GIRAFFE as BRACING.

Use the GIRAFFE CALCULATOR to verify the assembly support.

Find the course that suits you! rothoblaas.com

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 187

PARTIAL FASTENINGS AND INSTALLATION Partial fastenings may be necessary during the initial installation stages, but must never be considered sufficient to transfer loads for which they were not designed. A temporary connection with only a few fastenings may serve to keep the element in position, but not to withstand load conditions that require completion of the structural detail. Therefore, it is essential to verify that at every stage of assembly, no element relies on an insufficient number of fastenings or on temporary configurations incompatible with the loads.

LEGEND

very low risk

Connections compatible with temporary partial fastening during assembly.

risk to be avoided

Connections not compatible with temporary partial fastening: all fastenings must be installed before loads are applied in order to guarantee structural safety.

Structural behaviour of the connections

188 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

Reduce the need for temporary fastenings and the associated risks by using innovative RING and RADIAL connectors, pre-assembled or installed directly on site.

ROTHOBLAAS RECOMMENDS

RING

RADIAL

LBS HARDWOOD EVO

REMOVABLE CONNECTOR FOR STRUCTURAL PANELS

CONNECTORS FOR TIMBER BEAMS AND PANELS

ROUND HEAD SCREW FOR PLATES ON HARDWOODS

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 189

ASSEMBLY PLAN WORKFLOW

STEP 1

STEP 2

STEP 3

ASSEMBLY ORDER

DEFINITION OF TEMPORARY MEASURES FOR ASSEMBLY STABILITY AND SAFETY

PROTECTION TO BE APPLIED IMMEDIATELY AFTER INSTALLATION

CLIENT: XXX BUILDING SITE: XXX

NR.

CLT PANEL - 100 mm ( 20 + 20 +20 + 20 +20) 104.5 cm x 164.0 cm - NR.8 DATE: XXXXX

CLIENT: XXX BUILDING SITE: XXX

NR.

CLT PANEL - 100 mm ( 20 + 20 +20 + 20 +20) 104.5 cm x 164.0 cm - NR.8 DATE: XXXXX

CLIENT: XXX BUILDING SITE: XXX

The sequence for installing elements, subsystems and connections, consistent with the structural design and the progressive stabilisation of the works.

Temporary works and devices required during the intermediate stages: • propping • bracings • supports

considering

COORDINATION BETWEEN DELIVERIES AND SEQUENTIAL INSTALLATION

Measures to be adopted immediately on: • joints • edges • service penetrations and technical openings • exposed details to limit water ingress and protect the elements until the next stage.

considering

CHECKS OF TEMPORARY ASSEMBLY CONFIGURATIONS

The order of arrival, unloading, handling and installation of the elements, avoiding unnecessary build-up, reducing intermediate storage and ensuring continuous and controlled assembly. • temporary loads • localised storage • unbalanced installation stages • possible torsional effects • intermediate load paths

See further details on page 46

See further details on page 82

190 | ON-SITE MATERIAL MANAGEMENT PLANS | CONSTRUCTION PROJECT EXECUTION PLANS

STEP 4

STEP 5

STEP 6

CHECKS REQUIRED BEFORE THE NEXT STAGE

COORDINATION WITH FAÇADE, MEMBRANES, DRAINAGE AND ENCLOSURE OF THE BUILDING ENVELOPE

OPERATIONAL ROLES AND RESPONSIBILITIES OF THE BUILDING ENVELOPE

Identify the checks to be carried out before proceeding, particularly regarding correct positioning of the elements, adequacy of the fastenings, temporary stability, tolerances, continuity of protection and absence of critical conditions.

Ensure continuity between structural assembly and subsequent works, guaranteeing compatible timing between protection measures, watertightness, drainage and enclosure in relation to the exposure of the elements.

• Who gives the go-ahead for this stage • Who checks the temporary conditions • Who installs the temporary works • Who checks the protection measures • Who authorises transition to the next stage

See further details on page 46

See further details on page 156

For each element, indicate

ASSEMBLY PLAN OUTPUT

When it arrives How it is handled In what order it is assembled What temporary loads it generates or receives What temporary works are required

Which fastenings are permitted during the intermediate stages What protection must be applied immediately after installation Which checks must be passed before proceeding

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 191

SAFETY PLAN The Safety Plan is the cross-cutting document governing the other construction project execution plans for all aspects related to prevention and protection on site. It defines, for each operational stage, the measures necessary to ensure that works, assembly sequences, handling operations and temporary works are carried out under safe conditions. Applicable national regulations must be complied with. The site must be equipped with the necessary collective protection measures. Each operator must be protected with personal protective equipment (PPE) appropriate to the activity being carried out. The safety manager must supervise the correct application of the planned measures and their consistency with the various stages of operation.

HELMET

HERO

PERSONAL PROTECTIVE EQUIPMENT

HELMET FOR WORK AT HEIGHT, ON CONSTRUCTION SITES OR IN INDUSTRIAL AREAS

SLING

SPARTA COMPLETE PROFESSIONAL HARNESS FOR FALL PROTECTION SYSTEMS, POSITIONING, ROPE ACCESS WORK

GLOVES

GLOVE MID RECYCLED NYLON&SPANDEX/ NITRILE FOAM GLOVES

HIGHVISIBILITY VESTS

VEST HIGH-VISIBILITY GARMENT

SAFETY PLAN

CONSTRUCTION PROJECT EXECUTION PLANS

TRANSPORT AND LIFTING PLAN

MOISTURE MANAGEMENT PLAN

STORAGE PLAN

ASSEMBLY PLAN

TEMPORARY SAFETY WORKS

RAILINGS

COLLECTIVE PROTECTIVE EQUIPMENT

TEMPORARY LIFELINES

SINGLE ANCHOR SYSTEMS

BORDER

EDGE TEMP 1

ALUMINIUM PERMANENT AND TEMPORARY RAILINGS

TEMPORARY RAILING ROOF SIDE

HOLD SYSTEM

TEMPORARY

TEMPORARY HORIZONTAL ANCHORING DEVICE

TEMPORARY LIFELINE

WING

KITE

ANCHOR POINT FOR ROPE ACCESS WORK

ANCHOR POINT

Use TOOLGRAB to prevent tools from falling from height on site.

FALL PROTECTION NETS

OVERNET

HORIZONTAL NET

PERMANENT FALL PROTECTION SYSTEM FOR INDUSTRIAL ROOFING

HORIZONTAL POLYPROPYLENE FALL PROTECTION SAFETY NET

Use the carabiner for fastening fall protection nets.

CONSTRUCTION PROJECT EXECUTION PLANS | ON-SITE MATERIAL MANAGEMENT PLANS | 193

This catalogue is the exclusive property of Rotho Blaas and may not be copied, reproduced or published, totally or in part, without prior written consent. All violations will be prosecuted according to law. The most up-to-date technical documentation is available on the Rotho Blaas website. Rotho Blaas is not liable for any printing errors related to technical data, drawings, references to weights and measurements, and translations in the catalogues. Rotho Blaas reserves the right to modify its product range, characteristics, technical specifications and other documentation at any time without prior notice. Installers, designers, engineers, users and buyers must visit www.rothoblaas.com before each use of a product. Each product is designed for the specific load capacities and applications outlined in the technical documentation, in accordance with the limitations and additional information provided therein. While the products are engineered for a wide range of applications, Rotho Blaas disclaims any liability for determining their suitability for a specific use. It is the sole responsibility of the user to assess the product’s appropriateness for the intended application and to ensure proper installation. Each intended use of a product must be evaluated and approved by qualified professionals. Rotho Blaas does not guarantee the legal or design conformity of the data and calculations provided. The calculation tools provided are for indicative purposes only and serve as a purely technical-commercial aid to support sales activities. The values resulting from "test" are based on the actual experimental investigations results and valid only for the test conditions specified. Rotho Blaas does not guarantee and in no case can be held responsible for damages, losses and costs or other consequences, for any reason (warranty for defects, warranty for malfunction, product or legal responsibility, etc.) deriving from the use, inability of use or non-conforming use of the product. The images are for product illustration purposes only; they may not fully reflect the product’s characteristics and may have been created using artificial intelligence systems. Accessories shown in pictures and renderings may not be included. Packaged quantities may vary. In the event of discrepancies between the language versions of the catalogue, the Italian text shall be considered the official version and take precedence over all other translations. The general purchase conditions of Rotho Blaas Srl are available on the website www.rothoblaas.com. All rights reserved © 2026 ROTHO BLAAS SRL All renderings © ROTHO BLAAS SRL Publication date: 09/2026

PROTECT THE WINDOW Fastening, waterproofing and sealing determine the quality of the window installation. In high-performance buildings, tapes, sealants and fastenings ensure airtightness, water protection and a proper connection between frame and structure.

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This Smartbook is neither a guide nor a catalogue. It is a practical tool for identifying risks before they escalate into damage. It starts with the critical points where water can affect site operations: lack of coordination between construction stages, areas left exposed for longer than expected, and details that work on paper but perform differently on site. It does not replace the design. It helps you interpret the actual conditions on site, assess critical issues and choose workable solutions before the problem becomes irreversible.

Via dell‘Adige N.2/1 | 39040, Cortaccia (BZ) | Italia Tel: +39 0471 81 84 00 | Fax: +39 0471 81 84 84 info@rothoblaas.com | www.rothoblaas.com

COD

Rotho Blaas Srl

01SMARTCAN1EN 09|26

It is a tool for use on site.