Technical Focus Timber frame
STRUCTURAL INSULATED PANELS (SIP)
Timber frame copes excellently with complex designs. From single- to six-storey buildings, of any shape and size – timber frames have the added advantage of being able to offer both private and commercial developers a flexible building material. Modern timber frame structures are precision-engineered, strong and durable, although the same basic rules apply. The build method relies on timber frame as a means of structural support – carrying the loads imposed by the floors and roofs, before transmitting them to the foundations. The construction of timber frame-based structures utilises factory manufactured wall panels, alongside floor and roof panels, which are often referred to as cassettes. The systems used are classified as either open panel or closed panel.
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Open panel These are structural engineered panels that form the inside loadbearing leaf of the external wall, comprising studs, rails, sheathing on one face and a breather membrane. The open panel system is made from treated softwood timber framing, over which a structural sheet material of either Ply or OSB board is fixed.
Closed panel
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CLADDING BREATHER MEMBRANE SIP BATTEN (OPTIONAL) 12.5MM/25MM PLASTERBOARD 6. SHEATHING 7. CLEAR CAVITY
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TIMBER FRAME PANELS
These are made from studs, rails and insulation, with sheathings and/or linings on the faces of the panel. A vapour barrier is also provided on the warm side of the insulation and a breather membrane on the outer face of the panel. If desired, closed panels may also include fitted windows and internal service zone battens, for ease of installation and construction.
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Timber frame currently accounts for around a quarter of new homes in the UK, with over 75% of self-builders using the product as their primary build method. This type of build method is utilised by every sector of the construction industry and is very popular with low- to mediumrise residential developers and student accommodation providers. As with all forms of structural timber, timber frame has superb environment credentials, as well as being quick and easy to construct. There is a wealth of information available to construction professionals on the Structural Timber Association website, from advice on structural timber systems to market reports and an online member’s enquiry system.
www.structuraltimber.co.uk
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CLADDING BREATHER MEMBRANE SHEATHING INSULATION STUD WALL 12.5MM/25MM PLASTERBOARD 7. CLEAR CAVITY
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