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The Natural Philosopher

wrote:
stevelup wrote:

Hi

I'm in the process of refitting my bathroom and am seeking some tiling
advice.

Three of the walls have new unskimmed plasterboard, and the fourth wall
is made of ply (it conceals pipework and a cistern for the wall hung
WC).

Is it OK to tile directly onto these surfaces? If so, what preparation
is recommended. Finally, could someone suggest the best tile adhesive
to use?

Many thanks,

Steve

You can tile direct if you dont mind it all falling apart after 15
years, and having to redo it.

If its going to fail, it will be in the first year.

Plasterboard will die at teh first whiff of damp, and PVA won't stop it
either.

Likewise a soaking wet bit of ply wont last long, PVA or not.

Or do you see boat builders covering ply hulls in PVA to waterproof
them? No. I think not.

PVA is not waterpoof in any sense of the word. Its not even water
resistant. It WILL stop water soaking into to stuff like screed, because
it's already there instead. It WILL go white soft and scummy when it
gets wet, and fall off a surface.

If you want it to last better one thing
you need is a waterproof membrane, as tiles really cant be counted on
to be waterproof,

That's why they are used in bathrooms, swimming pools, and on house
rooves of course. To let the water pass freely. That's why we make
basins out of glazed china, like wot tiles are made of, to let the water
soak out. Thats why toilets, also made of glazedse porcelain, leak and
dribble everywhere.

Sometimes you are a pillock.

Tiles are 100% waterproof. The only think you need to worry about is
grout, which is why you need to use a setting type grout that won't
degraded under water, and fill its pores with your blasted PVA, so
although the PVA softens when wet, it won't let water migrate through

Tiles can be couunted on to be waterproof. Your tiling apparently,
cannot. That is YOUR problem however.

and both ply and PB are vulnerable to water. The
othing thing is the right adhesive. The BAL site has guides on these
things.

Of course they are vulnerable. Guess why we put TILES ON THEM?

NT