Upstand
An upstand is the vertical section of membrane or flashing at a flat roof edge, parapet, or abutment that prevents water tracking behind the waterproofing system.
Ask Chalkline about this →An upstand is the vertical portion of a waterproofing membrane or flashing that turns up from a flat or low-pitch roof surface against a parapet wall, raised kerb, or any vertical abutment. Its job is to prevent water ponding on the roof surface from tracking behind the membrane at the edge.
Under AS 4654.2:2012 Appendix A, the minimum upstand height above the finished roof membrane surface is 150 mm in standard wind zones, with higher requirements in severe and very severe wind exposure classifications (verified 2026-05-10). An upstand shorter than this allows wind-driven rain or deep ponding to top the membrane and infiltrate the structure.
The upstand must be physically bonded to the vertical face, not simply turned up. A counter-flashing or termination bar at the top of the upstand locks the membrane against the wall and prevents wind uplift.
Also known as: kerb, upstand kerb.
Category: Flat roof / external waterproofing.
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Last updated: 2026-05-10. Verified: 2026-05-10. Quarterly review for currency.