TRADA develops standard details for thermal performance
To address the revisions to Approved Document L (ADL) which come into effect in October 2010, TRADA Technology, with the UK Timber Frame Association, led a workshop last month to collate industry comment and guidance on the future of timber frame thermal bridge detailing.
TRADA has commissioned modelling of the details contained within the TRADA Technology publication Timber Frame: Standard details for houses and flats. Lewis Taylor of the company's Building Performance Division said, ‘These details are a good representation of current timber frame industry practice and will enable us to develop thermal details for use in SAP calculations. The TRADA details offer an improvement over accredited construction details and would result in a reasonable improvement in performance in SAP calculations.'
The TRADA details will offer an appealing solution to designers, architects and timber frame manufacturers, said Mr Taylor. ‘They can adopt and build to them and use the individual Ψ-Values in the SAP calculations. When the overall Y-Values are calculated, it shows that our standard details achieve 0.05 when mineral wool insulation is used between studs.'
Unfortunately, because these details are not currently accredited or part of a recognised accredited scheme, a 25% or 0.02 W/mK penalty must be applied resulting in an overall Y-Value of 0.07. ‘Even so, the TRADA Technology details still exceed the performance of the current accredited construction details and as such are a viable alternative to adopting them.'
The initial round of calculated thermal details will be available for download by the end of this month, free to TRADA and UKTFA members. Non-members will be able to purchase them from the TRADA bookshop www.trada.co.uk/bookshop. For more information on the project contact Lewis Taylor on 01494 569668 / .
