Aftercare
Plastering Aftercare & Decorating FAQs
The questions customers most often ask once the plastering is finished, from drying times and hairline cracks to the first coat of paint.
Part 1 of 4
The first few days
“It's all dark pink and patchy. Is that normal?”
Yes, completely. Fresh plaster is full of water, so it starts dark pink or brown and dries to an even pale pink. The patchiness is simply some areas drying faster than others. As a rough guide, a skim coat over plasterboard takes about a week to dry. A full replaster over backing coats can take four to six weeks, and longer in cold or damp weather.
“How do I know when it's properly dry?”
The whole wall should be one even pale colour with no darker patches, especially in corners and around windows, where drying is slowest. If a patch is still dark after a few weeks, let me know, because it could point to damp behind the wall.
“Should I put the heating on full to speed it up?”
Please don't. Drying too fast is the most common cause of cracking. Gentle, steady background heat is fine. Ventilation matters more than heat, so open a window or two and leave the doors open to let the moisture escape. Avoid pointing heaters, fan heaters, or dehumidifiers straight at the wall, particularly in the first few days.
“Can I touch it or lean things against it?”
Try not to for the first day or two, because it will mark easily. Keep furniture a few inches away from the walls so air can circulate while it dries.
Part 2 of 4
Little things you might notice
“There's a hairline crack. Has something gone wrong?”
Fine hairline cracks are usually normal. Plaster shrinks slightly as it dries, especially where it meets the ceiling, in corners, and around doors. Fill them with a fine filler before decorating and they'll disappear. Wider cracks, or a patch that sounds hollow when you tap it, are a different matter, so give me a call.
“There's a white fluffy powder coming through in places.”
That's efflorescence, which is salts drawn out of the wall as it dries. Brush it off with a dry brush and don't wash it, because water just brings more salts to the surface. It usually stops once the wall is dry.
“Can I clean the splashes off my skirting and floor?”
Yes. Dried plaster splashes usually flick off with a plastic scraper, and a damp cloth will clear what's left. Avoid metal scrapers on painted woodwork.
“Should I sand the walls before painting?”
A good skim shouldn't need sanding. At most, give any filled cracks or small nibs a very light rub with fine paper. Heavy sanding scratches the smooth finish and makes a lot of dust.
Part 3 of 4
Decorating: the important bits
“Can I just get my normal paint on it?”
Not straight away. New plaster is very porous and will soak paint up unevenly, so it needs a sealing first coat called a mist coat. This is usually a trade or contract matt emulsion watered down. Check the tin for the manufacturer's recommended ratio, but roughly three or four parts paint to one part water is typical. Alternatively, buy a ready-made paint designed specifically for new plaster, which saves the guesswork.
“Why can't I use vinyl paint or a silk for that first coat?”
Vinyl emulsions, including vinyl matt and vinyl silk, form a plastic-like skin that traps moisture in the wall. Any moisture still in the plaster then pushes the paint off, and it peels or bubbles. Contract matt is breathable and lets the wall finish drying. Once the mist coat is on and the wall is fully dry, your topcoats can be whatever you like.
“Should I brush PVA on before painting?”
No. PVA leaves a surface that paint struggles to grip, and it can cause peeling later. A mist coat is the right primer for paint.
“Which finish will make the walls look best?”
Matt is the most forgiving. It hides small imperfections and looks soft and even. The shinier the finish, such as silk or gloss, the more it shows every slight undulation, especially on walls that get low-angle light from a window. Good-quality paint also makes a noticeable difference, because cheaper paints often need more coats and can look patchy.
“What about my kitchen and bathroom?”
Use the mist coat as normal. Then, once the walls are dry, a dedicated kitchen or bathroom paint is well worth it, because these are made to resist moisture and mould and to cope with wiping down. Keep the extractor fan running and ventilate well after showers, especially in the first few weeks.
“When can I wallpaper?”
Only once the plaster is fully dry, and never earlier than you would paint. Seal the wall first with a mist coat or wallpaper size so the paste doesn't soak in and the paper slides into place properly. This also makes the paper much easier to strip in future.
“How many coats will I need?”
Usually the mist coat plus two topcoats. Stronger or darker colours may need a third.
Part 4 of 4
Living with it
“When can I hang pictures, shelves, or a TV?”
Wait until the wall is fully dry. Plaster alone won't hold anything heavy, so use fixings suited to what's behind it: plasterboard fixings for board walls, and wall plugs into masonry for solid walls. For TVs and heavy shelving, fix into studs or solid masonry.
“Can I wash the walls?”
Leave fresh paint a couple of weeks to cure before scrubbing. After that, gentle cleaning with a damp cloth is fine, and wipeable paints will handle more.
“Who do I call if something doesn't look right?”
Sam, any time. Tell me about anything unusual, such as persistent dark patches, hollow-sounding areas, or cracks that keep growing, and I'll come and take a look.