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The Timber Industry Yearbook 2011 Timber Research And Development Association www.trada.co.uk
Timber frame
The simplest solution to these potential problems will be to use unsheathed party walls or only sheathe one leaf. With open or partially open party walls, the insulation can be easily installed once the building is made weathertight. It is also possible to perform site checks. As with masonry cavity walls, if fully sheathed timber frame walls are used and the insulation installed during erection, subsequent checking and snagging would be very difficult. Timber frame is ideally suited to buildings with repetitive layouts such as flats and care homes, so the new Part L requirements may bring some changes in detailing and order of work, but it will also bring valuable overall improvements that occupants will benefit from, not least valuable savings on fuel costs. Because much of a timber frame building is constructed offsite on a clean, efficient and well-managed production line, the quality of the end product can be enviable. This helps on site by reducing material waste, simplifying and speeding construction methods, and delivering a building to the client that performs well against the new regulations. Using a truly sustainable material, offering high insulation values, quality construction and good air tightness, new timber frame buildings are well placed to meet the evolving needs of planet earth and its occupants.
Party walls unsheathed for ease of insulation
with no assumed heat loss. Therefore, it is likely that thermal insulation will need to be installed between the studs as well as in the cavity between the two leaves of the wall, allowing zero heat loss to be assumed. Achieving this on site may require some changes to current practices. Installation of the insulation between fully sheathed party walls during erection may slow the build progress, as additional time would be needed. Also, ensuring that the insulation remains dry and does not become dislodged during the rest of the build may be difficult.
Supporting Services TRADA Technology has several publications on timber frame construction and thermal performance: • Timber frame: standard details for thermal performance • Timber frame construction, 4th edition, Huel Twist and Robin Lancashire Visit www.trada.co.uk/bookshop or telephone 01494 569602
Robin Lancashire says the new Part L brings party walls under the microscope for the first time