Bathroom tiling

(And so we move on to next room)

We have 3 plastered walls and 1 stud wall with aquapanel - whole room to be tiled floor to ceiling

Floor at the moment is mositureproof t&g

Been reading and have conflicting info

Should we replace the t&g with exterior ply ?

Then backer board and tiles ?

I'm guessing the existing stuff is t+g m/r chipboard ? if so then you have a couple of choices:

1. overboard it with a backerboard such as no more ply, then use a single part flexi addy on top. (this is my personal preference)

2. rip it up and replace with 20mm WBP ply, then use the same addy as above.

The main reason that chip is so frowned on is because if you get a leak if falls to bits and no amount of overboarding can stop that, so some prefer to use ply which i agree with fully if you havent started yet.

You can tile direct if you abrade the wax off then use a s2+ addy like granfix ultimateflex, but TBH we see failures not from the adhesive but from the subfloor too often to suggest this method, plus the addy is very expensive.

See here
http://www.tradepricetiles.co.uk/blog/tiling-on-chipboard-floor/

overboard with nomore ply, hardie backer board or take the chipboard up and replace with 19-25mm wbp ply making sure its firmly screwed down to the joists, then using a single part flexi tile away. Replacing the floor with wpb would be my option, does not leave you with a step to contend with like overboarding, and there is no dodgy subtrate beneath the overboaring. Only thing worth mentioning is that if you choose to replave the floor, seal the edges and underside of the wpb ply before screwing down

As a footnote

We have left off cuts of the mositureproof chipboard on the garden for the last 2 weeks. Still totally in tact even after rain and cold temperatures etc

kazzab said:

As a footnote

We have left off cuts of the mositureproof chipboard on the garden for the last 2 weeks. Still totally in tact even after rain and cold temperatures etc

Click to expand...

Indeed, We have some that is fine after a good few months outside.