A new skim coat usually takes several days to a week to dry in good conditions. Backing coats and full replasters take longer, often two to four weeks before the wall is dry right through. Cold, damp weather and rooms with no heating or airflow slow things down.
How to tell when plaster is dry
Fresh plaster starts dark brown and turns an even light pink as it dries. If you can still see darker patches, usually in corners, behind radiators or low down on the wall, it needs more time. Painting too early traps moisture, which leads to flaking and blistering.
How to help it dry
- Keep the room ventilated by opening a window slightly.
- Keep the heating on low and steady rather than blasting it, which can cause cracking.
- Avoid dehumidifiers in the first day or two, when fast drying can weaken the surface.
Painting new plaster
New plaster is very absorbent, so start with a mist coat: a cheap white or magnolia matt emulsion thinned with water. It soaks in and seals the surface. Once it is dry, apply your normal coats of paint. Avoid vinyl or wipeable paints for the mist coat, because they sit on the surface and can peel.
Need a hand?
We leave every customer with clear advice on drying and decorating for their job. If you are planning a reskim or a full replaster in London or Kent, call us on 07515 569399 for a same day quote.
