Freshly plastered walls are a great blank canvas, but you don't want to go straight in with a couple of coats of your normal emulsion.
New plaster is very absorbent, so the first coat needs to be suitable for a bare surface. Prepare the surface correctly and the rest is pretty straightforward.
Here's how we'd tackle it.
How long should you leave new plaster before painting?
There's no magic number of days that works for every plastered wall.
A thin skim can dry fairly quickly, while thicker plaster will take longer. Temperature, humidity and ventilation will all have an effect as well.
The easiest thing to look at is the wall itself. Fresh plaster is usually a darker pink or brown and becomes much lighter as it dries. If you've still got obvious dark patches, it needs more time to dry completely.
You want the plaster to be completely dry before painting, so always check the instructions for the paint you're planning to use.
Do you need a mist coat on new plaster?
In most cases, yes.
A mist coat is simply the first coat you put onto bare plaster. A suitable water based paint can be thinned with clean water, which helps it soak into the porous plaster and gives the following coats something to bond to.
What you shouldn't do is automatically use the same paint to water ratio every time.
You'll see 70% paint and 30% water mentioned all over the internet, but there isn't one mist coat recipe that works for every paint.
For example, the instructions for Dulux Trade Supermatt, Crown Trade Covermatt, Leyland Trade Super Leytex and Johnstone's Trade Jonmat all differ.
So keep it simple: check the instructions for the paint you're using and dilute it accordingly.
What paint can you use on new plaster?
There are a few good options that you can use:
Dulux Trade Supermatt
Dulux Trade Supermatt is probably one of the best known choices for new plaster. It's a high opacity matt for interior walls and ceilings.
For sealing new or bare surfaces, Dulux currently recommends thinning the first coat with up to one part clean water to three parts paint.
Crown Trade Covermatt
Crown Trade Covermatt Obliterating Emulsion is another paint specifically intended for first time decoration and new plaster.
It's a good option for new builds, extensions or anywhere you've got a lot of fresh plaster to get through. Crown's instructions currently specify a mist coat diluted with 40% clean water on porous surfaces.
Leyland Trade Super Leytex
Leyland Trade Super Leytex is a popular contract matt with a breathable, permeable finish, making it particularly well suited to new plaster.
It's also got good opacity, so it's a useful choice when you're decorating larger areas of fresh plaster.
Leyland recommends sealing absorbent surfaces with one part water to nine parts Super Leytex.
Johnstone's Trade Jonmat Premium Contract Matt
Johnstone's Trade Jonmat Premium Contract Matt is another breathable contract matt suitable for new plaster and plasterboard.
For sealing new or bare surfaces, Johnstone's instructions allow the paint to be thinned with clean water, so again, follow the ratio given on the product before starting.
All four are available from Next Day Paint, so you've got a few options depending on the job, budget and finish you're after.
How to paint freshly plastered walls
1. Check the plaster
First, make sure the plaster is ready to paint.
Look for any darker areas that still appear damp and check the instructions for the particular paint you're using.
If in doubt, giving it a little longer is better than rushing it.
2. Sort out any imperfections
Have a look over the wall for trowel marks, raised bits, scratches or small dents.
Remove any obvious raised imperfections and lightly sand or fill where needed. There's usually no reason to sand an entire freshly plastered wall if it's already been finished well.
Once you're happy with it, remove any plaster or sanding dust with a brush or vacuum.
3. Apply your mist coat
Now it's time for the mist coat or first coat system recommended for your chosen paint.
Decant some paint into a clean container, add the correct amount of clean water and mix it thoroughly.
Apply it evenly with a brush and roller.
Don't panic if it doesn't look brilliant when you've finished. A mist coat isn't supposed to give you a perfect finished wall, its job is to prepare the plaster for the coats that follow.
4. Check the wall again
Once the first coat has dried, have another look at the surface.
Paint has a habit of showing little dents and imperfections you couldn't see on bare plaster.
If you spot any, fill them, sand them smooth once dry and remove the dust. Touch those areas in again if necessary before moving on.
5. Apply your finishing coats
Once everything is dry and the surface is prepared, you can apply your chosen finishing paint.
You'll usually need two coats for a good, even finish, but follow the instructions for the paint you're using and allow the correct drying time between coats.
You don't necessarily have to stick with a contract matt for the finished wall either.
In bedrooms, ceilings and lower traffic areas, a standard matt finish may be all you need. For hallways, living rooms and other areas that take more knocks and marks, you might prefer something more durable such as Dulux Trade Diamond Matt once the new plaster has had a mist coat.
Should you use PVA before painting new plaster?
Generally, no.
PVA gets mentioned a lot when people talk about sealing new plaster, but for normal decorating you're better off using the mist coat or primer recommended by the paint manufacturer.
You want the first coat to bond with the plaster rather than creating a separate sealed film between the wall and your paint.
A few mistakes to avoid
The biggest ones are pretty straight forward:
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Painting plaster before it's ready
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Leaving sanding dust on the wall
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Using normal emulsion at full strength without checking whether it's suitable
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Assuming every mist coat should be 70/30
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Worrying because your mist coat looks patchy
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Using PVA instead of the paint system recommended by the manufacturer
The bottom line
Painting new plaster isn't particularly complicated.
Make sure the wall is ready, sort out any imperfections, remove the dust and use a paint that's suitable for bare plaster. Most importantly, follow the dilution instructions for the product you're using rather than relying on a generic mist coat ratio.
At Next Day Paint, we stock a range of paints suitable for new plaster, including Dulux Trade Supermatt, Crown Trade Covermatt, Leyland Trade Super Leytex and Johnstone's Trade Jonmat Premium Contract Matt, alongside more durable finishing paints for once the walls are prepared.
Get the first coat right and you've got a solid base for the rest of the job.
