I've recently had my hall walls skimmed and having waited several weeks for the plaster to dry out I went straight ahead and painted a single coat
of matt emulsion directly onto the walls.
I realise now that I should have sealed or primed the wall first. What should I do now?! Should I wait a few weeks and see how it fairs, sand it down and try sealing the walls afresh or just carry on painting and hope for the best?
What sort of matt emulsion? It can really make a difference.
If it was "rich matt" you are in trouble as it doesn't stick to new plaster and will have to come off. As emulsion paints take an average 30 days to fully cure you might as well start now. Ditto if it was silk - I know you said matt but just for completeness I mention that.
If it was cheap and very thin own-branded stuff from one of the sheds you may get away with it as there is so much water in it that using it neat is tantamount to a mistcoat with Dulux Vinyl Matt.
If it was "supermatt" again you'll probably get away with it but I bet you didn't half get through a lot of it if it wasn't thinned for the first coat.
If it was "paint for new plaster" it should be OK but you've overpaid for your paint as its just marketing hype and fancy packaging.
BTW when you say "seal and prime" the way you do this is with a mist coat of watered down emulsion paint. Nothing else!
Come back with the type of paint you've used (unless I've given you the answer above) and lets see where we can go with it.
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