wet room floor advice

[Chrisjs]

Hi All

Great forum, hoping for some advice on a wet room I'm planning.

I need to lay a new subfloor so was going to use 22mm WBP. Should I be leaving gaps between the boards? I was planning to lay ditra heat on top and that mentions using tongue and groove boards instead.

should I lay kerdi board over the ply before the ditra heat?

any advice on a shower former to use with ditra heat?

thanks

 

[Flintstone]

I think you would be wise to insulate the floor before fitting the ditra heat. I'm not an expert on the schluter system, but @impish uses it a lot

 

[One Day]

Hi, you can use wbp or t&g boards, no issue with either as long as deflection-free.
Kerdi-board under the ditra heat? I have never used it on floors, despite Schluter claiming you can. It would insulate and help speed warm-up times.
There is Ditra Heat TB now which has a thin thermal layer on the matting - might be an option for you?
As for shower former - I would use Schluter with Schluter so how about Kerdi Shower LS board with a kerdi line drain and tileable grate?

 

[One Day]

Thanks for the mention @Localtiler

 

[LM]

I was told Ditra heat is good to go on top of plywood!

 

[Chrisjs]

Super, thanks for the advice. I'll check out the ditra heat TB

Thanks

 

[Chrisjs]

@impish I looked at the the kerdi shower ls but the specs give a height of 32 or 36mm which will give a step up from the ply floor. Any recommended alternatives that will give a level floor?

Thanks

 

[One Day]

@impish I looked at the the kerdi shower ls but the specs give a height of 32 or 36mm which will give a step up from the ply floor. Any recommended alternatives that will give a level floor?

Thanks

In short - no! At 32mm they can be set flush with joists (if you can get away with sinking the drain assembly at (from memory 80mm) into the centre joist/s.
It's a complete faff but worth doing.
More often than not I convince customers that a raised deck looks great and if there are no mobility issues - why not?
Schluter and Wedi are German made and their houses don't as a rule have wooden floors like ours, hence the problems.

There are Impey, Delta, etc trays which can be as low as 22mm on the edge but in my view they are a second best option and require lots more experience, skill and care to ensure they are bonded and waterproof.

Picture below shows an 1800mm tray without a central screen and x2 hinged wings.

 

[Flintstone]

Schluter have started doing some 'trade' wet room kits I beleive, a package with all the bits

 

[One Day]

Schluter have started doing some 'trade' wet room kits I beleive, a package with all the bits

They have. But you try finding them anywhere other than on-line!
Same old - same old problems with Schluter. It's been years now and their distribution is still terrible.