Concrete panels on bathroom walls?

[WetSaw]

I wouldn't use a foam cored board behind a wall hung toilet with thin tiles.

 

[Jonathanb]

Cheers, I thought it may be a bit dodgy. Double 12mm plasterboard?

John

 

[Old Mod]

One more question. I am fitting a wall hung toilet and vanity unit. What thickness Kerdi board would be best to use under Porcel-thin tiles?

Cheers
John..

I generally fit 18mm ply behind where the toilet will hang, just around the footprint of the toilet plus 20mm or so, so that the ply takes the weight of the toilet and not the backer board and tile.
If you’re going t sit the toilet on the tile and not cut tight around it, drill all your holes, do not cut out a diamond shape to accommodate pipe work.

 

[Dumbo]

So do you not anything between tile and plywood other than adhesive and if not do you scrim the joints or anything like that .

 

[Jonathanb]

Why does the Kerdi

I generally fit 18mm ply behind where the toilet will hang, just around the footprint of the toilet plus 20mm or so, so that the ply takes the weight of the toilet and not the backer board and tile.
If you’re going t sit the toilet on the tile and not cut tight around it, drill all your holes, do not cut out a diamond shape to accommodate pipe work.

View attachment 99063

Cheers, I will use 18mm ply. I have plenty. Then 19mm Kerdi board around it.
Cut a diamond shape ? How rough do you think I am

John..

 

[Old Mod]

So do you not anything between tile and plywood other than adhesive and if not do you scrim the joints or anything like that .

Yes I’ll tape joint Jerry, but look at it this way, you have two bloody great 10 inch bolts pulling the toilet and ply on to a frame, with just enough ply sticking out to sit on metal frame. Exactly where is it going to go? Drilled holes have a much higher chance of success than a sodding great hole with a pan stuck to it.
The point of it is that the ply will not crush at all, where’s as the same cant be said for backer boards can it. (Obviously depending two things, how accurately the plumber has secured the pan, and secondly, who exactly is going to be putting their full body weight on the pan. If the substrate flexes, so will the tile. And if anything does develop a leak, it’ll be behind the boarding anyway no matter what it’s made of.

 

[Old Mod]

Cut a diamond shape ? How rough do you think I am

John..

Haha it’s not about being rough John, it’s like anything else, cutting a diamond is quicker and much more forgiving than trying to drill 4 holes in the exact place they need to be.

 

[Old Mod]

I wouldn't use a foam cored board behind a wall hung toilet with thin tiles.

Haha didn’t even see your post til now.

 

[Jonathanb]

I would of drilled the holes anyway, not just cut a chunk out. I will be taking my time doing it all. As you can probably guess I have done a fair amount of research on it all
It’s just a pain all my joinery tools are all pretty useless to help me out doing this type of work. Well apart from a laser level and a cordless drill.

John..

 

[Old Mod]

I would of drilled the holes anyway, not just cut a chunk out. I will be taking my time doing it all. As you can probably guess I have done a fair amount of research on it all
It’s just a pain all my joinery tools are all pretty useless to help me out doing this type of work. Well apart from a laser level and a cordless drill.

John..

Just but Cheap electroplated drill bits John from someone like @Pro Tiler Tools
Get some 6mm mdf or Kerdi board offcut, drill hole in that first and use as a template over tile.
Do not drill directly perpendicular to the tile, start at 45o with theedge if the drill, and slowly stand it up as you drill, then use sight oscillating movemet with your wrist. If you drill square, you’ll donthe drill bit in one hole. The cheap ones will last you the job. Tear a bit of sponge up and force it up inside drill bit, dip it in water and it’ll help keep it cool.