Hi,

Does anyone know if it would be possible to use a Marmox shower drain with Kerdi membrane (under small mosaics)?

Thanks,
Adrian

Hi Adrian and to the forum

Yes mate this will be fineThe Marmox drain is the waste kit and the Kerdi is the tanking membrane so just make sure the Kerdi is integrated with the drain in the correct manner and you'll be fine.

Do you have a Marmox tray as well and what are you fixing the Kerdi with?

Thanks for the quick reply.

I'm hoping to make the "tray" by sloping some mortar down to the drain, and then laying Kerdi over the mortar and the surrounding floor.
I was just worried that I might not be able to fix the Kerdi into the drain, between the K-frame and main seal.

Adrian

Is it a timber base or concrete Adrian?

I was hoping you wouldn't ask that!

18mm osb3 flooring. I was going to cut out a circle about 1m diameter, then board between the joists as for a proper tray. I was going to extend the kerdi well beyond the circle. I didn't want to use Ditra, as then I'd have to use it all over the floor, which would be a bit pricey.

OSB I'm assuming you don't want to replace the entire OSB floor, which is what I would be inclined to do....

My route would be to install a Wet Dec/Marmox tray, by cutting the desired tray area out, strengthening the joists beneath and boarding between the joists as you had previously suggested. The WetDec tray is 22mm thick which will leave the tray about 6mm proud of the rest of your floor with a thin adhesive bed beneath the tray - this would then be eliminated by overboarding your OSB with 6mm Hardie Backerboard and then Kerdi tanking your base and walls
Probably a bit more work than you had hoped, but safer IMHO

Thanks for the advice. I've been fascinated with all the posts about tiling on wood! Really helpful, that's where I found out about Ditra/Kerdi etc.
As you say, rather more work and expense than I really want. I'm only a DiYer, so not too serious if I get cracking in the mosaics, but provided I can dress the kerdi into the drain ok, at least it should never leak.

Thanks again,
Adrian

provided I can dress the kerdi into the drain ok,

That part shouldn't be any trouble to you Adrian

Good luck and keep posting on TF - I'm sure one of the other lads will come along and offer a cheaper option for you later today