Reply To: Painting directly onto plaster

[keith]

Assuming this is new plaster you are painting? If so, then, as suggested by others, a light sand and a mist coat is the the thing.

A light sanding is all you should need: if it’s new (decent) plaster the surface should be flat and fairly smooth so it should just need any knibs removing, then sanding to provide a key if the plasterer polished it a bit too much. You just want to remove any shine,no need to go overboard. Just ‘float’ the sanding block over the wall and you should feel any imperfections. Ideally, try to look along the wall with a window/light-source at the other end and you will see any knibs or other imperfections.

It doesn’t sound as if doing this would make much difference but, as bedspring said, it really makes it look smart – assuming your painting is up to scratch, obvs.

Tip for the mist coat: dilute about 1:1 but ensure you give it a really thorough stir, ideally use an electric paint whisk, otherwise you’ll end up with water on some of the wall and thicker paint on the rest. The mist coat should look fairly even and well-covered.