Building Regulations

U value calculations

New BRE software available

Part L (England & Wales) and Part J (Scotland) require that U values are calculated to BS EN 6946, a method that is a refinement on the proportional area calculation method currently used.

As manual calculations are unlikely to be practical, software has been developed by BRE through a DTLR-funded PiI project, which has partners from many sectors of the building materials industry.

The BRE U-Value calculator obtains U-values in accordance with the methods set out in: BS EN ISO 6946; BS EN ISO 13370; BS EN IS0 10077-1; BRE IP 10/02; SCI P312; BRE Digest 465.

It covers most types of building elements and can be purchased for £20(+VAT) for immediate download at www.brebookshop.com.

Guidance on the use of the calculation methods is contained in BR 443. Conventions for U-Value Calculations also available from www.brebookshop.com.