Tiling a shower

[leenowell]

Hi All,

We are fitting a bathroom and have tiled the shower area. My wife went to b uy BAL grout today and noticed it said it was suitable for showers but was water resistant not waterproof. So.... She called their technical support. They said it should only be used on the wall the shower is on if the wall h as been tanked/ waterproofed (using some waterproofing paint) first.

Is this correct as I have never heard of this before? Also.... We have now fitted the tiles with their adhesive which seems to say the same thing (ie for showers but only water resistant).

Anyone know?

Thanks

Lee.

[Rob Morley]

You're supposed to use Aquapanel* (cement-based glass-covered wall board rather than gypsum-based paper-covered) for showers.

• Other brands of similar specification are available.

[leenowell]

Yes I used Hardie Backer on the stud wall the shower itself is on. The othe r wall is brick and plaster. My fear is more that if the grout/ adhesive is not waterproof eventually the wall will become damp. TBH not sure what it means "suitable for showers" if not waterproof.

Thanks

Lee.

[Rob Morley]

It means it won't weaken and fall out when wet. You need to stop the plaster wall from getting wet by applying something that acts as a barrier to water, not just something that doesn't mind getting wet. Having said that, you'll probably get away with it, for a while anyway.

[leenowell]

Thanks Rob for your reply. Yes the plaster was sealed with a sealant for new plaster before you tile so assume that covers that angle.

So in summary of I understand correctly, the water may get the grout and the adhesive wet but ingress further would be stopped my either the plaster sealer or the Hardie Backer board. Also neither grout or adhesive will degrade because of the wet.

Is that correct?

Thanks again

Lee.

[Rob Morley]

Yes, except I don't know what the "plaster sealer" is that you used. Is it just to stop the plaster from sucking the tile adhesive dry, or does it provide a permanent barrier to water?

[Brian Gaff]

My guess is that if water gets into the cracksand hence into the wallsomething could um, give.

[Andy Burns]

glass-covered? I'd go with cement-based with embedded glass-fibre mesh.

[ss]

I know this is not good but for what its worth, about 20 years back I retiled my ensuite and never having done it before and not having the same access to the internet I just ripped off the old tiles, made a mess of the existing plasterboard, gave a rough skim and put on new tiles and dont remember getting a `special` grout.. I knew nothing about waterproofing etc back then. After 15 years I retiled and the wall behind the tiles was still good, the shower was used daily, although a rubber sqeejee thing was used to take excess water off the tiles after showering.

Moved house and redone this shower room using aquaboard, I hope that lasts as long :-)

[Vir Campestris]

We've just had our bathroom rebuilt.

One of the timbers behind the shower wasn't just a bit damp, it had rot and quarter inch holes where some _big_ beetle had been chewing it.

Andy

[newshound]

Correct. It is a little bit like old fashioned cement-asbestos board, but with the asbestos replaced by glass fibre. It also has a somewhat harder and smoother surface.