Floor waste suitable for waterproofing drainage

[emptybucketman]

Hi All,

Is there a particular name for a floor waste that allows the water collected by the waterproofing membrane to drain? What is needed and what do I need to do? At the moment I just have the 4 inch PVC drain pipe coming up through the concrete floor. The floor screed will be laid over the membrane.

Regs
Wes

[journeyman Mick]

Either a "Rock top grate" which is a flange and grate complete with the grate able to angle to the flange to allow for misalignment/different fall between the floor and the screed, or a "puddle flange" to which you'll need to add a suitable grate. A bit hard to describe exactly how they work but when you have one or the other in your hands it will be readily apparent.

I just rteread your post and I'd suggest you lay your membrane over the screed. Both ways are acceptable, but with the membrane under the screed, if you get any quantity of water into the screed it could end up smelling bad, puddle flange or not.

Mick

[emptybucketman]

Thanks Mick,

1) I'll get my hands on a puddle flange, but are there special grates or can I just use any grate with the puddle flange?

2) Is water pooling and the resulting smell, a common problem with bathrooms where the waterproofing is done before the screed? Should I be concerned...

[journeyman Mick]

Wes,
1)just have the puddle grate in hand when you buy the grate and make sure they work alright together.
2)Don't know if it's common, just possible. You might get away with it, but then again............

Mick

[bricks]

Here In adelaide a "puddle flange" is different to what you want being a "leak control flange" You should have at least a 50 mm flange on the edge.

[silentC]

I'm pretty sure that a standard flange will fit any standard floor waste, at least we didn't go out of our way to make sure of it and they fit. But as Mick says, just buy them both at the same time and you should be OK.

If you put the screed down first, does the flange go at floor level or screed level? How do you get the membrane continuous with the flange? Would be good to know for next time, even though there isn't going to be a next time...

We put our flanges in, then the membrane, which laps over the edges of the flange, then the screed. We also cut a recess for the flange so that it finished flush with the floor, so that the fall into the flange across the membrane was continuous. That way any water under the screed will run into the flange and not collect at its edge. That's the theory anyway.