stud wall/plywood for shower

[dune]

can anyone help please

have had a stud wall built for a shower and the builder has bought 18mm plywood for the wall of the stud wall and the flooring ready for tiling.
Is this correct as the wood seems rather think and it means that there is going to be a smalll step into the shower room, which i didn't really want. the plywood is also to go over current floorboards and then be tiled

any advice welcome
thx

 

[White Room]

Could use 12.5mm hardie backer board for the stud wall and 6mm hardie for the floor boards. You don't say what tiles are your using, also is there any bounce on your bathroom floor.

 

[cornish_crofter]

I would go with 12.5 hardibacker, CTD in our area have got an offer in it. £7.50 plus VAT buys you a 1200x800 sheet. cheaper than Topps or any builder's merchant.

Screw this in with plasterboard screws.

As has been said, 6mm over existing floorboards for the floor.

It seems that your builder is going the extra mile to do the job right but may not realise that there are better products out there.

 

[grumpygrouter]

What product you use on the floor really depends on how rigid the floor is. If there is bounce in the floor then he would be correct to try and strengthen it with 18mm ply. Better to have a small step than cracked tiles. If the floor is strong enough, then 6mm hardie would be my choice (or 6mm wedi but it is more expensive). Personally don't like the idea of Ply in a shower area.

 

[dune]

thank you to all of you for your comments and help.
will look into them