laying floor tiles on chipboard upstairs?

[browfish]

Hi
I have jsut put in the joists and laid the 18mm chipboard deck for my bathroom in my new extension. Next job was to tile the floor. I have 300x300mm porcelain tiles to go down but the tile shop have told me not to tile onto chipboard especially the green stuff, and instead i should lay 15mm ply over the top.
Is there any other way as i dont really want to raise the floor by this amount.
I am planning on putting a walk in wet room style shower and was going to tank the area with aquatechnic aquaproof. If i did the whole bathroom would this provide a bonding layer between the tile adhesive and the chipboard?
thanks

 

[masona]

Hi
I have jsut put in the joists and laid the 18mm chipboard deck for my bathroom in my new extension. Next job was to tile the floor. I have 300x300mm porcelain tiles to go down but the tile shop have told me not to tile onto chipboard especially the green stuff, and instead i should lay 15mm ply over the top.

Pity you didn't put exterior (WPB) plywood down instead of chipboards, as you're in the early stage best to take the flooring up again, a pain I know but will be worth it in the long run as it will give you the same floor level height

 

[browfish]

Thanks masona.
Is that really the only way. Is there nothing i can paint the floor with to make them stick?
Mind you i have to take some of the floor up anyway to make the wet room.

 

[Galena1]

Hi browfish - Bite the bullet and use plywood, do you really want to be repeating this exercise in the future? If you do decide to take up the existing chipboard, whilst it's up put in plenty additional noggins between the joists to help keep any flexing to a minimum. I always used a two part latex-based adhesive for fixing tiles on timber floors. Make sure you clean any excess from the joints and face of the tiles whilst it is still wet, it's a pain to shift once its dry. My personal preference was Mapei adhesive and grout, there are, of course, other makes. The same applies with the grout re proper cleaning off before its dry. Regards.

 

[browfish]

hi, thanks for comments
Just to update, i have spoken to the techincal department at aquatechnic about there aquaproof product for tanking wetrooms. They have advised me that this is fine to us on chipboard and suggest covering the whole room anyway. Hence i have ordered enough to cover the bathroom floor in this which the tiles will then adhere to. I ahve also been to see a colleagues bathroom who did exactly the same thing and is as good as new nearly 5 years later.I will ad a few extra noggins though as the ceiling underneath has yet to be boarded so should be easy.

 

[masona]

Nothing wrong with that providing you're happy with the extra floor height.

 

[prceramics]

would recomend laying Schlüter-DITRA mat on top of the chipboard is only 2 to 3 mil thick

 

[browfish]

Thanks for that
Tiles were installed 5 years ago now and i have moved house since then but appreciate the input