As the housebuilding industry looks to meet Government and demographic demands for 250,000 new homes a year, the employment of timber-based systems will increase dramatically as they already constitute the most popular branch of offsite construction.
In fact, the advent of engineered timber solutions such as glulam, SIPs and CLT or cross-laminated timber has expanded the systems' suitability and experience for meeting different challenges.
Timber is accepted as being highly sustainable though, as an organic material, it is susceptible to differential movement or ‘settlement'.
This is an issue which is magnified when employing timber for multi-storey structures where cumulative loading leads to greater relative movement between the structural frame and the cladding - normally brickwork - at the upper levels. However, the technical and aesthetic challenges this presents can be effectively dealt with through use of the illbruck system: detailed in the manufacturer's Timber Max brochure and covered by a BBA Agrement certificate 12/4891Product Sheet 5.
The system features the use of the well proven Compriband 450, a soft and flexible open-cell polyurethane foam, which is installed on the inner or warm side of the structure above and below the window openings. This combines with Tremco-illbruck ME500 membrane, lapping onto the window frame, and Compriband 601 which permits the window jambs to slide vertically as the building moves.
Not only has Compriband been developed to accommodate the 37mm of movement expected in buildings up to six storeys, the system also offers buildability through ease of installation and an encapsulating sleeve that is removed once brickwork mortar has dried.
Together they provide the accuracy, consistency and robustness required to enable timber frame systems to realise their potential as rapid build, well-insulated solutions for today's construction industry. Crucially, the illbruck system helps maintain weather resistance and airtightness in line with the principle of creating Fabric First or PassivHaus type envelopes which are moisture-tight on the warm side and vapour-open on the cold side.
In contrast to conventional construction techniques, the illbruck system using Compriband 450 avoids the problem of return visits to deal with cracked silicone seals or windows sticking due to pressure bearing on the frames as well as cills lifting and rotating.
