plaster primer

[huckin]

hi ive brought some mapei plaster primer and would like to no what mix it should be diluted for tiling as the instructions aren't clear thx

[akinsontiles]

This is the technical data sheet from Mapei for ECO Prim http://www.mapei.com/public/COM/prod...rim%20t_gb.pdf

Which adhesive are you using that requires the primer?
What size are your tiles too?

[huckin]

hi im using 300 by 300 wall tiles and im using fast set mapei adhesive

[akinsontiles]

Be cautious about the weight limit with those tiles 20kg max including adhesive and grout onto skimmed plasterboard.

Fast set mapei adhesive doesn't tell me the type of adhesive. I take it that it's a cement based one suitable for walls as well as floors by the sound of it. I would recommend one such as P9 or P10 for large format on the walls with back buttering a must.

You are quite right using a primer as the cement would react against the gypsum and not bond correctly causing it to come off later on.

[huckin]

hi when you say back butter do you mean spread the wall and the tile if so what trowel size do you think i should use 8mm thx for the replys

[huckin]

oh and yes it is cement based not tubbed

[Aspect Tiling]

You got it. Apply adhesive to the wall as normal with the notched trowel, and using the flat flat side of the trowel spread a thin layer of adhesive over the back of the tile. 8mm trowel will be if the walls are relatively flat.

[akinsontiles]

yeah back buttering simply means serate the wall as normal and spread adhesive over the reverse side of the tile so that you get 100% coverage and its bonds adhesive to adhesive rather than adhesive to ceramic/porcelain. Good practice to follow on all jobs to avoid failures but especially important on large format tiles or those with ridged markings on them from the kiln process.

Was that data sheet any good for the primer you got or was it a different product?