Hi, I've just rid a small wall of old plaster to reveal some old brick , some partially painted. I've scrapped, smoothed and sanded to try to get rid of any excess paint and now have a reasonable conditioned wall to plaster. I would like to PVA the wall first but there seems ambiguity over how long I should leave the PVA on the wall prior plastering. As the main purpose should be as a primer should I leave to PVA on for an hour or so ? I have heard people say leave it overnight but I'm sure this is wrong. Could someone kindly confirm.
cheers
uc