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Painting & Decorating Question
Covering patchy plaster and oil based eggshell in bathroom
External wall has patchy plaster and filler from some blowing, and was painted with oil based eggshell. I have got most of the paint off, but some won't budge. Question is how do I prepare the wall for painting, do I rough sand the eggshell I can't get off, and size the old rough plaster, with watered down emulsion paint or pva? Also, What paint should I use for the top coat? I was thinking acrylic eggshell as I want to also paint the wooden bath panels with the same paint, is acrylic ok for a poor plaster background? Some old areas of filler is very soft and chalky.
Thanks in advance.
Acyrlic eggshell is ok to go over oil based eggshell (as long as the oil based is quite old) just give it a good key. If its gone back to bare plaster then a thinned coat (50/50) should be applied to the bare plaster only, Don't use PVA! some people say to seal with that but they are WRONG when it comes to painting!. After all the bare plaster has had a miss coat then acrylic eggshell would be fine. If you have any doubts about the walls you can seal them all with a primer sealer or similar. You must make sure the plaster is FULLY DRY though for all this to work,most paints should not be applied to a substrate that has a moisture level of 18% of more.
Answered 10th Aug 2012