Porcelain tiles 300x600

[thompson_2009]

Hi

I have 300x600 7mm porcelain tiles and the bathroom wall is plasterboard.

If i scrape the thin plaster of the board and use a cement base adhesive would that be okay?

i know with plaster on the board the tiles are to heavy.

 

[opps]

Plain plasterboard 32kg per m2 (max weight load)

Skimmed plasterboard 20kg per m2 (max weight load)

8mm porcelain tiles weigh about 20kg per m2

source: https://www.leafcutterdesign.co.uk/tiling-weight-guide/

Can you remove the skim coat without damaging the paper face?

Regarding the weight loading- I have never been sure if those figures are tension loads or shear loads.

 

[Paul C.]

You "might" be ok with heavier but you are not adhering to British Standards and therefore voiding all guarantees with the adhesive and tile manufacturers. More importantly, you could be sitting in the bath when the plaster decides to fail and a tile in the head would kinda hurt a bit. Personally I don't think its a risk worth taking.

You cannot used ready mixed adhesive on any tile above 300x300 so the cement based adhesive is a must. If you go onto plasterboard, tank it first. Another option if you wanted to go belts and braces would be to remove and replace, or overboard the plasterboard with Marmox boards, screwed into the studs.