Another tiling question.

[haph]

Morning all,

I have an external toilet which I want to tile the walls up to about 1.2m above the floor. The problem is I didn't intent to do this before, just wanted to put a row of one tile above the floor and paint the rest of the walls with semi-gloss paint. I have now changed my mind . The walls are 6mm fibre cement and I have painted them with one coat of undercoat. Is it Ok to tile over the paint undercoat or I have to scrape them off before tiling? The undercoat is British Paint 3in1.

Thanks for your input.

Haph

[mic-d]

Adhesive companies will tell you that it should be on primed cement board. Although your undercoat is probably not the recommended primer, it should have soaked in enough that it is unlikely to be a layer sitting on the surface that may peel off down the track and take the tiles with it. Nor is it a top coat with additives like teflon that the adhesive may not bond to. So I think you will be fine, but use a cement-based flexible adhesive rather than a mastic since there may be a prolonged drying time for the mastic on a sealed surface.

Cheers

Michael

[haph]

Thanks Michael. Your reply is much appreciated.