Tanking New Shower Area For Wetroom - No Tray

[EViS]

We're about to start work on a new wetroom installation on a ground concrete floor. The shower area is to be triangular with two of the sides 'kicking back' a tad (see attached sketch). As such shaped shower formers/trays do not exist, we're going to have to create the fall to the corner drain with some slc or tile adhesive.

So, questions:

1. Does it sound sensible to install 10mm insulation, underfloor heating and SLC, up to the point where the shower area will begin? Hence, the bathroom floor area will be some 20mm higher than the shower area before tiling. This will allow us to create the fall to the corner drain in the shower area (see attached sketch)? This would also save us digging up a large part of the concrete floor.

2. The shower area will measure approximately 1.2 x 1.2 metres. Will a fall of 20mm (as illustrated) suffice to the corner drain?

 

[PHG Dave]

In answer to your questions, yes to both, but have you considered how you are going to waterproof the floor?

 

[EViS]

Thanks for the reply.

I have, and seeing as it's a concrete floor, I will probably tank the entire floor and 150mm up the walls with Dura-ci to prevent the stone tiles from fracturing. Or are there better alternatives?

 

[Tony73]

I think it's 80 to 1, so you have 10mm fall in 800mm. 1,2m = 15mm fall

 

[Qwerty]

Have you not thought about buying a Marmox pre-made fall board.... this could easily be cut to suit the shape of your shower area.... 3 sections as illustrated below

 

[EViS]

No I didn't realise a Marmox board could be cut to the correct falls... Thanks for the heads up.

 

[Qwerty]

It is essentially a wedge shaped board that you could cut to suit

 

[AliGage]

I was going to ask what the measurment is from the corner out to the diagonal and suggest a tray as well. Perhaps this one:

Orbry Wet Room Shower Tray 1200 x 1200 x 30mm (Corner Drain)

I have a 1850 x 900 x 20mm offset centre in the garage. If you can make use of it i'll do you a deal.