Ponding / Flood Test
Plugging the outlets, flooding a completed waterproofed area and holding the water — typically 48 to 72 hours — while the space below is observed for any sign of ingress.
On an actual building
It is the only test that proves the system works before it is buried under a screed, tiling or landscaping. Finding a fault afterwards means removing everything laid on top of it.
What we most often have to correct
That it can be done after the finish is laid. At that point it tests the finish, not the barrier.
Terms that come up alongside this one
- Fall (Slope)
The deliberate gradient built into a horizontal surface so water runs to the outlets, usually around 1:100 to 1:120 on a terrace..
- Upturn (Skirting)
The vertical continuation of a waterproofing layer up an adjoining wall or parapet, terminated mechanically at the top..
- Protection Board
A sacrificial board or screed laid over a completed waterproofing membrane to shield it from mechanical damage by following trades or backfill..
Ponding / Flood Test — questions we get asked
What does ponding / flood test mean in waterproofing?
Plugging the outlets, flooding a completed waterproofed area and holding the water — typically 48 to 72 hours — while the space below is observed for any sign of ingress.
Why does ponding / flood test matter on a real project?
It is the only test that proves the system works before it is buried under a screed, tiling or landscaping. Finding a fault afterwards means removing everything laid on top of it.
What do people commonly get wrong about ponding / flood test?
That it can be done after the finish is laid. At that point it tests the finish, not the barrier.
Have a building showing this?
If a term on this page describes something you are looking at, a site inspection will tell you how far it has gone and what it needs. It costs nothing.
Mon–Fri 08:00–18:00 · Sat 09:00–16:00 · Jogeshwari West