In article ,
Rob Horton writes:
Jut finishing off the tiling in my kitchen and I have only the window
box left to do. The Plaster surface was a bit uneven and raw so I have
sealed it with a PVA solution and let it dry.

Suddenly wondered if that was the right thing to do? Or Am I going to
have to scrape it back to bare plaster?

Tile cement has incredible bonding properties, and will probably
stick to it OK (at least the powdered stuff; I've never used
ready-mixed so I can't comment on that).

When PVAing under plain sand and cement, you should apply the
sand and cement to a layer to still tacky PVA. However, tile
cement contains its own bonding agents and prefers a dry
background, so I think it should be OK on dried PVA, although
I wouldn't have put the PVA on in the first place.

--
Andrew Gabriel
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