Shower Waste fitting to suit Waterproofing over Screed?

Dear Vern,

Fair call. Theoretically - probably none, I guess...

I'm just envisaging that it would be hard to get the Screed right up to the opening of your existing PVC Pipe or Eathernware Opening (so that it offered full support to the underside of the Puddle Flange), without a fair amount of the Mortar falling into the Pipe/Opening when you pushed the Flange into it...

If you could simply extend the existing Pipe upwards out of the penetration by about an inch or so (ie. the proposed thickness of your Screed around the Waste), there would be no problem, but the trouble is - there's no straight-couple fitting (as far as I know) that "Males" inside a 50mm pipe (as opposed to "Femaling" around it, which you obviously can't do with an existing concrete slab in the way...). If it's upstairs - through a timber floor - you should be in business...

But suffice to say, if you could get your pipe up and out of the slab by the desired thickness of your Screed, you could simply then Screed up to it, and then push down something like the LCMEGASD50RND (7th from the top on this page: http://www.artplastics.com.au/leakControl.asp) while the Screed was still wet, and then Waterproof onto the edge of the Flange when the Screed has set.

Out of interest Vern, what thickness of Screed were you going to go down to at the Waste end of things?

Many Thanks,
Batpig.

Dear Vern,

Originally Posted by Vernonv

I think this is what you are looking for - product SR50SO on http://www.artplastics.com.au/genPlumbProd.asp.

Awwww, you are The Man! Nicely spotted! That's just what I need. May the wind be ever at your back Vern...

Best Wishes and Many Thanks,
Batpig.

Dear Andy,

That looks and sounds like it will work to me, but the only thing is, it appears that the LCTRAY50 goes around a 50mm drain pipe (rather than inside it), so you'd have to be in a position to be able to do this, including the joining with the PVC Primer and Cement...

Best Wishes,
Batpig

ahh I hadn't realised, it could have beena problem thanks for that ..
my plan was to:
1. place the slab repair connector upside down on the 50mm pipe
2. cement up to drain level,
3. Pull it off before the cement dries...that way I can go inside or outside it if need to with the flange

so does anyone know if a leak control flange essential for an above screed waterproofing membrane?

Thanks again
Andy

Dear Andy,

So it sounds like you'll use the slab-repair fitting as formwork to create a cavity in the screed with a diameter that is the same as a 50mm drain, that will feed down and straight into the actual drain-pipe...

I'm no expert on the subject whatsoever, but in terms of waterproofing theory from where I sit, I guess the idea sounds okay, as long as the "precipice" (ie. the upper edge of the little mortar cavity you've created) isn't so sharp that your membrane ends up so thin over it that it eventually cracks at that point. If you could "round-over" the edge of the precipice you should be okay.

That would then boil it down to two further issues:
Firstly, you would need to get the membrane all the way down the cavity and lapping into the pipe, so that shower waste-water isn't able to soak back into your screed underneath your membrane. It would eventually end up coming out in the ceiling below if you're on an upper floor, or attracting termites if you're on the ground floor.
Secondly, you'd have to make sure that the vertical inner-edges of the little cavity weren't so weak, or so high, that they ended up crumbling away into the drain. This could really be an issue if you're just "dry-packing" the screed into place around the slab-repair piece that you are using as formwork. Screed has plenty of compressive strength, but not as much "anti-crumble" (for want of a better term) about it...

Best Wishes,
Batpig.

Hey Batpig,
the slab repair is not so much for framework but to allow an annulus around the 50mm pipe and to prevent the cement from getting in.. I intend the 50mm pipe to be near level with the surface, that takes away issues such as those mentioned about crumbling cement and sharp edges. I was going to use a very narrow flange to provide a curved surface, which goes around the outside of the 50mm pipe and waterproof down into tthe pipe about 50mm.. the LCTRAY50 is just much wider platform version but same principle.

Groovey.. I think the solution is adequate, so long as the membrane goes into the drain, and so long as the edges are protected from cutting / tearing.

Thanks again,

Andy (I'll post some pics when I get around to doing it, feel free to do the same )

Gents,
please check the photo, this the shower drain pipe which was embedded in the floor concrete slab which i am changing to use leak control flange, 2 questions:

the pipe is not vertical (90 deg to the floor), any solution other than digging it out and setting it straight?

is it ok to embed the pvc pipe in concrete? shouldn't there be a sleeve of some sort?
Thanks

Dear Sannawi,

If your Waste-pipe is not entirely straight ( ), you need to be looking at one of the "Megaflex"-type Puddle-Flanges, which use a rubber O-ring on the spigot to enable a seal with the Waste-pipe at less-than-perfect angles. You also get greater versatility with the vertical positioning of the assembly, to boot...

They start at the third unit down on this page at the Art-Plastics website:
http://www.artplastics.com.au/leakControl.asp

With regard to burying the PVC pipe in concrete, as far as I know, it's not only okay - it's actually essential for waterproofing reasons when it comes to penetrations through a slab. You might instead be thinking about where a pipe comes through a footing, in which case compressible "lagging" should be used to allow for vertical movement in the foundation soils between wet and dry weather seasons.

Best Wishes,
Batpig.

2) What would be the best adhesive to stick the Flange down to the top of an existing concrete slab?

Try Sikaflex 11FC or depending on the plastic Fulaprene 303