What are the critical points in the building envelope to which particular attention should be paid when sealing joints?

All joints in the building envelope - whether on the outside or inside - should be permanently and functionally sealed against driving rain and / or airtightness. Unfortunately, this is not always the case. This makes careful planning and the use of tested systems all the more important.

What is the difference between façade joints and window connection joints?

We differentiate between connection joints according to load groups. The window connection has to fulfil different functions than a façade joint (dilatation joint). In order to fulfil the functions reliably and permanently, the sealing products must be selected appropriately; a façade joint must be permanently protected against weather influences such as UV light or driving rain greater than 600 Pascal and should also be open to vapour diffusion. Our BG1-M 接缝密封胶带 fulfils all these functions. The window connection joint is usually continuous from the outside to the inside. In order to achieve a functioning, tight joint, we have to divide the joint into three sealing levels. At the outer level, the 防暴雨ness is greater than 600 pascals, and UV resistance and vapour diffusion openness are required. The layer in the centre of the window must ensure thermal insulation and soundproofing, while the inner sealing layer must ensure airtightness.

Primary and cross joints in façade construction are particularly challenging to seal. How can these joints be permanently protected against the effects of weathering such as UV light and driving rain?

Our BG1-M 接缝密封胶带 fulfils precisely these requirements. The BG1 tape is tested in the cross joint and is also open to vapour diffusion. The BG1-M can be installed regardless of the weather - even at temperatures below 5 °C and in the rain. It is compatible with known building and sealing materials. Edge zone discolouration, as can occur with silicone oils, is ruled out here. There is also no need to apply an adhesion promoter (primer). The tape does not bond to the joint edges as it is only inserted into the joint. The sealing function is guaranteed solely by the contact pressure to the joint flanks, which prevents the flanks from tearing. The product fulfils the highest Ecobau and Minergie-ECO requirements with regard to ecological and health specifications and has eco1 and GEV Emicode EC1 Plus ratings. Hanno guarantees object-related functionality for up to 15 years, including UV and weather resistance. All tapes are 测试按照 DIN 18542.

Are there differences in the sealing of windows in new builds or renovations?

Hanno offers various connection systems for the different window connections in new builds, timber construction, concrete element construction and window renovation. With our multifunctional tapes, all three levels are sealed 按照 standards using just one product. The advantages of this product are, on the one hand, the very simple and quick installation and, on the other, the very good sound insulation properties of 59 decibels joint sound reduction index. Alternatively, the inner and outer joints can be sealed with the 表面全自粘 Duo Easy film, while the outer and inner joints are sealed with Duo Easy - a 表面全自粘 film tape. This film tape is resistant to driving rain, moisture-variable and 可以抹灰 without any problems. All the above-mentioned window connection products fulfil the ecological and health requirements and are Minergie Eco and EC1 Plus certified.the thermal insulation of the middle connection of the window joint can be carried out with Hannoband-Therm or with Hanno PU foam.

The upper area of large-format lift and slide doors presents a challenge when it comes to sealing - what exactly is the problem and how can it be solved?

A lift and slide door is usually very wide and therefore the ceiling is self-supporting over many metres. With a self-supporting ceiling, deflection of up to 15 mm is to be expected. To ensure that this deflection can be absorbed without damage, a joint approximately 3 cm wide must be planned in the upper area. The joint seal must absorb the movement without damage. Our multifunctional tape 3E is suitable here, as it fulfils all functional levels and compensates the pressure permanently and functionally.

For aesthetic reasons, windows are often installed on the outermost level of curtain wall façades. Are there any special sealing requirements?

The In-front-of-wall installation system is particularly suitable here: The advantage lies in the high load transfer and the optimisation of the thermal bridge. The system is bonded to the masonry in a watertight and airtight manner. The window can then be installed as with a normal perforated window using the multifunctional tape 按照 standards. The window can easily be replaced from the inside at a later date.

The interview was conducted in collaboration with Hanno (Schweiz) AG.

_________________

Hanno (Schweiz) AG, based in Sissach, was founded in 2000 as an independent branch of Hanno Werk GmbH & Co. KG, which is based in Laatzen, Germany. Among other things, the company specialises in sealing connection joints in building construction and sound insulation.

© Docu Media Schweiz GmbH 2024 (https://www.baudokumentation.ch/aktuelles/hanno-schweiz-ag-interview-fenster-und-fassaden-abdichten/47081837)