If the proper time is not allotted for drying and curing, you could be setting up for a disastrous situation. Improperly dried out plaster can lead to some of the most sinister paint peeling issues that one can imagine.
However, we'd recommend leaving it for at least two weeks if possible to be safe. In the wrong conditions, plaster can even be known to take up to four weeks to dry! The colour of the plaster should help you tell whether or not your walls are ready to be painted.
There's no harm in postponing decoration for a while, in fact it will give the plaster time to dry out fully and any subsequent shrinkage cracks can be filled before painting. The only downside in a kitchen area is the risk of grease spots and splashes which would resist a subsequent water based paint.
While some may suggest plastering and painting on the same day, it's essential to allow the plaster to cure before applying paint. Waiting for the plaster to dry completely, typically for around two weeks, allows all moisture to evaporate. This helps prevent issues such as paint peeling in the future.
With freshly plastered surfaces, leave approximately six months to dry completely before painting.
Before painting your wall, you need to let the plaster dry completely. Painting over plaster when it's not dry can cause problems later, so if in doubt, always wait until you're confident it's dried completely.
Can you paint directly over old plaster? You should only paint onto old plaster if it isn't flaking or cracked. If it is in poor condition, you should repair and/or use sandpaper before you begin painting. Any imperfections in the surface will show through even multiple layers of paint.
For gypsum plaster, we generally recommend waiting around 24 hours between coats. This period allows the plaster to harden and set properly, providing a sturdy base for the next layer.
If the paint is in good condition and not in need of any maintenance, it is perfectly fine to skim over it with plaster. However, if the paint is old, flaking, or damaged, it is recommended to remove it before plastering.
Over time and throughout seasons, the fluctuations can cause plaster degradation, including cracked and sagging plaster. Of course, moisture can cause staining and bubbling, while temperature changes can cause cracks.
Unsealed plaster is porous and therefore rather dusty. Whilst we never saw evidence to this or felt like the room was particularly dusty, if you rubbed against the walls, you would often get a layer of dust on your clothing.
Without the mist coat you're likely to have very poor adhesion between your paint and your plaster and quite often it will crack, flake or even peel off in sheets in some instances!
Freshly-plastered walls should be smooth on the whole but you may find the odd plaster splash or pieces of dust that have been left. Use a fine sandpaper and a brush to remove these blemishes but don't be too vigorous with your sanding.
Fresco is a mural painting technique that involves painting with water-based paint directly onto wet plaster so that the paint becomes an integral part of the plaster.
Leave the plaster to dry
There are different factors that influence how soon can you paint on new plaster, such as the type of material and weather. As a rule of thumb, plaster takes up to 4 weeks to dry completely. You can speed things up with a heater or by opening a window.
1. Scrape or sand off any lumps and apply a second coat around 170–200mm wide using the 200mm broadknife finishing slightly wider than the previous coat. 2. Smooth down the joint edges with a trowel to reduce the need for sanding later.
This is because the moisture interferes with the adhesion process and prevents the plaster from bonding to the surface. For this reason, it is important to make sure that you apply the plaster to a clean, dry surface. Remember, simply replastering or painting over damp walls only treats the symptoms and not the cause.
Don't paint directly over new plaster walls because the glossy surface can prevent the paint from adhering effectively. Instead, once you've protected your work area with dust sheets, lightly score the walls with 150-grade sandpaper to create a key and improve adhesion.
Final Thoughts. Using roll on filler to skim a wall is quick, easy, and gives a great result. It's a lot cheaper to buy a couple of tubs of Dalapro Roll Nova than it is to hire a plasterer, and you'll have a full room skimmed in no time.
The reason behind bubbling in the plaster wall
If your interior plaster wall doesn't have a damp-proof coating on top of the paint, you are more likely to face dampness issues. Here, the moisture rises through the wall, and bubbling appears.
Let the plaster dry
Your plaster will dry quicker with a heater or if you open a window. If you try to apply paint to wet plaster this can cause adhesion problems. Applying emulsion to wet plaster also means that it may not bond properly and you could find that it peels off your wall.
Perhaps most useful are oil primer's ability to fill and seal the surface of the plaster. Kilz brand primers are known for their stain-blocking capabilities and are available at many home improvement centers. For a premium option, Sherwin Williams offers durable primers specifically for plaster.
Once the plaster has been repaired, you will then want to paint. You should still apply a mist coat to the old plaster.