BS 6229

BS 6229: 1982, Code of Practice for flat roofs with continuously supported coverings, requires rooflights to incorporate upstands to raise the mat least 150mm above the uppermost roof surface to which the roof covering is bonded or dressed. The designer should ensure that the builder’s curb is at least 150mm high.

BRE BR443

Various standards deal with the calculation of U-values of building elements. The conventions provide guidance on the use of the standards, indicating themethods of calculation that are appropriate for different constructional types, providing additional information about using the methods and providing data relevant to typical UK constructions. The U-value conventions were originally published by the BRE in 2002 and the 2006 edition is an update which provides additional information and reflects changes in the underlying British Standards. The U-Value calculation methods are also referred to in Approved Documents L1A, L1B, L2A and L2B.