Flat Roof Upstand Height

This should be measured from the top of the finished roof level and is designed to provide comprehensive waterproofing protection at abutments and around penetrations like drainage pipes.

Flat roof upstand height.

The job of an upstand sometimes referred to as a kerb is to lift the glass element of your rooflight off of the roof s surface and is required by building regulations for safety and weathering reasons. This dimension should be measured from the finished surface of the roof which would. Which would include abutments rooflights and service vents etc must have a minimum height of 150mm. The overflow must be a minimum of 25mm below the top of the 150mm upstand height.

British standard bs 6229 2003 flat roofs with continuously supported coverings section 7 page 12 requires that. British standard bs 6229 2003 flat roofs with continuously supported coverings section 7 page 12 requires that. The upstand is usually installed on a pitch to allow water to drain off the rooflight further increasing the upstand height. The design of drainage falls should ensure that the continuity of the waterproof covering is maintained for a vertical height of 150mm above the finished roof level at all abutments door openings and parapets.

The design of drainage falls should ensure that the continuity of the waterproof covering is maintained for a vertical height of 150mm above the finished roof level at all abutments door openings and parapets upstands are there to deal with the fact that rainwater can build up on a roof during heavy storm events. The requirement for flat roof upstands is set out in the british standard. Bs 6229 2003 flat roofs with continuously supported coverings code of practice and bs 8217 2005 reinforced bitumen membranes for roofing code of practice both state that if unwanted water ingress into the building is to be avoided all weatherproofing upstands occurring around the roof area. The minimum upstand height for a single ply membrane flat roof is 150mm.

Note also the requirement for an overflow if the waterproofing covers an enclosed area with an upstand all around such as on a balcony or roof terrace with a parapet. The upstand must be at least 150mm in height and should a minimum pitch of at least 3 degrees. The requirement for flat roof upstands is set out in the british standard.