Wetroom: how do a create a raised floor?

[Louisa]

I have a silly toilet / shower arrangement: the toilet is in a separate room behind the shower room and accessed via a bedroom. If I take down the wall between them, I end up with a corridor room, 3.3m x 1m, with a door at one end. As you walk in, then, there would be the wash hand basin, the shower and behind it, the loo.

So, if I swap the positions of shower and toilet, and put the shower at the far end, toilet in the middle of the long wall, all will work 🙂 But I have to deal with shifting the soil pipe for the loo, and the best way I can think of doing it is to put in a raised floor for both shower and toilet, which will accommodate the soil pipe and shower waste beneath it, so the last half of the 'corridor' will be perhaps 9" higher than the rest.

Now, I like wetrooms, and I like to be able to shower off the toilet when I've cleaned it, it just makes so much sense, so by doing this and making the whole platform a wetroom floor, I fulfil my dreams. Well, perhaps not all of them, but you know what I mean! I'm quite handy, so I'm not worried about doing this, but some advice would be welcome, mainly about how strong the new raised platform needs to be. I could use blocks and concrete but for ease of building and plumbing, I'd prefer to use wood. I'm thinking a 3x2 frame with a 3/4" waterproof chipboard top as a substrate for the tiling. I would like a gully rather than a single point waste, too. Full bed waterproof tile cement, waterproof tile grout with a return up the wall for a few inches, normal tiling above.

Does this sound like a plan?

Louisa

 

[micko]

Does the soil pipe go straight through the outside wall and then down, it may be easier to core drill a new hole through the wall and do all the soil plumbing outside. The fall needs to be around one in forty. Too steep or too shallow will give you problems. I'm not a tiler but I don't think chipboard is the way to go.

 

[Louisa]

The soil pipe dives straight into the floor, below which is a vaulted arch of stone work, not territory I want to go into. Party walls are very thick and not external, they are neighboring houses. Tapping into this soil pipe is the only way to go.

I'm interested to hear from others on the chipboard question. I could go with concretous stuff here, but the thicknesses over the soil pipes will increase and then the platform will be getting too high. And laying blocks instead of woodworking is hell on my nails! *blonde moment....*

Louisa

 

[micko]

I am out of my depth here but have done some casual reading on the forum. Plywood and then cement tile backer boards are normally recommended. The ply has to be fitted so there is no deflection at all, well supported. I am not sure if you can get away with ¾ ply and then a 6mm board.

As for your wet room you need to do some reading, there are many ways of tanking your walls and many different types of formers/ shower trays you can use. Not a simple task.

 

[Diggy]

How about something like this , ply shuttering , screed to height with falls , tile. Shuttering is around 200mm as I recall.

Edit: Didnt do the piccies correctly soz , not too hot on the pc



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