Hi, I am about to tile my upstairs bathroom and have removed the original floorboards. I was going to use 25mm ply and lay on top of the ply. I have read a load of posts on this and other sites and each gives different advice. Is it okay to lay directly on top of ply. I will be using flexi adhesive and grout. I will also be priming the PLY first!.
Tiling bathroom floor over 25mm PLY
- Thread starter marlb
- Start date
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Is the ply Marine, WPB or exterior grade? It should be, but if that is the case, do not prime the face that you are tiling as it will hind the bond of the adhesive. Seal the back and edges with a suitable SBR primer (not PVA).
But to be honest, wood, in a potentially wet or humid room??? I wouldn't be doing it as there are better options that I'd opt for. In those conditions a single sheet of ply can swell, expand, contract, rot!
Now we just await the onslaught of other time served tilers saying "i've always tile onto ply in wet areas and never had a problem". but never say never. I have seen horror stories that end up being extremely expensive to fix later. So why risk it? If no-one had any problems, why would they invent other products more suited to the job?
If anything a cement board like hardibacker is by far a more suited surface to tile onto. Lay an WPB Ply base (18mm)screw it down every 300mm into the joists. Lay the cement boards brick bond and cross-bonded with the ply to make sure the ply joints are all bridged. Screw down at a max of 300mm intervals in each direction, and stick a waterproof tape over the joints.
With the right tile correctly fitted, that will last for yonks.
But to be honest, wood, in a potentially wet or humid room??? I wouldn't be doing it as there are better options that I'd opt for. In those conditions a single sheet of ply can swell, expand, contract, rot!
Now we just await the onslaught of other time served tilers saying "i've always tile onto ply in wet areas and never had a problem". but never say never. I have seen horror stories that end up being extremely expensive to fix later. So why risk it? If no-one had any problems, why would they invent other products more suited to the job?
If anything a cement board like hardibacker is by far a more suited surface to tile onto. Lay an WPB Ply base (18mm)screw it down every 300mm into the joists. Lay the cement boards brick bond and cross-bonded with the ply to make sure the ply joints are all bridged. Screw down at a max of 300mm intervals in each direction, and stick a waterproof tape over the joints.
With the right tile correctly fitted, that will last for yonks.
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