how do i paint new plaster? an expert guide

For new and old houses alike, the benefits of plaster are numerous. Creating a smooth and durable surface with improved insulation and soundproofing properties, it’s no wonder that so many people look to plaster their walls. But then what? Unless you’re a fan of the fresh plaster vibe, you’ll be looking to paint your new surface, which begs the question: how do I paint new plaster?

Well, that’s what we’re here for! In this expert guide, we’ll take you through how to paint over the concoction of cement and sand known as plaster. From the equipment you’ll need, to preparing your mist coat, to the finishing touches, it’s all here!

At a glance:

• Equipment You’ll Need
• Choosing Your Paint
• Before Picking Up a Brush
  • Allow the Plaster to Dry
  • Smooth Your Surface
  • (If Applicable) Create Your Mist Coat
• Prepping and Painting New Plaster
  • Apply Your Mist Coat (If Applicable)
  • Apply Your Primer (If Applicable)
  • Apply Your Topcoats
• Final Thoughts: How Do I Paint New Plaster?

equipment you’ll need

As with any project, the right tools for the job will significantly increase your chances of successfully painting fresh plaster. Luckily for you, we’ve compiled a list of everything you’ll need to follow the upcoming steps, as well as some all-important guidance on choosing the right paint.

• Paint for mist coat or a suitable plaster primer
• Topcoat paint
• Water
• Mixing bucket, kettle, or paint tray
• Paint stirrer
• Dust sheets
• Decorators tape
• Small edging paintbrush
• Medium pile roller
• Sandpaper and filler (as required)

choosing your paint

For those wondering how do I paint fresh plaster, keep in mind that it’s not exactly a walk in the park. Choosing the wrong paint can make it an even trickier process. What’s the saying? Don’t bring a gun to a knife fight? Well, don’t bring your high-gloss or vinyl-based paint to new plaster either…

mist coat

We’ll go into more depth about mist coats later, but suffice it to say for now that a mist coat is basically a watered-down emulsion paint that acts as a primer.  You don’t always have to use a mist coat, especially if your plastered surface is old or particularly rough, where it might require a specialist primer instead. However, using a mist coat is adequate for tackling new plaster and eliminates the need to purchase an entirely separate and often expensive product. So, when choosing your mist coat paint, there’s a few pieces of advice we recommend you follow:

• Pick a water-based emulsion paint – We love water-based paints anyway for their eco-conscious qualities and health benefits, but when it comes to painting new plaster, they are especially important due to their breathability.
• Opt for a matt finish – Since the aim of a mist coat is to effectively seal the plaster by allowing the surface to absorb the paint, choosing a matt base is probably your best bet as it enhances absorption without creating an impermeable film.
• Choose a light colour or a colour very close to your topcoat shade – It might seem obvious but choosing a particularly bright or dark colour for your mist coat will cause more work for you later down the line as it can impact the final topcoat colour, requiring more coats to achieve the desired finish.

topcoat

When it comes to your topcoat paint, you have a lot more flexibility as much of the hard prep work will already have been done by the mist coat. Generally speaking, though, here’s a few things to bear in mind when choosing your topcoat paint:

• Don’t discount breathability – When it comes to newly plastered walls, the surface should be allowed to breathe. New plaster needs to release moisture, so opting for a breathable topcoat will work with the mist coat to avoid adhesion problems such as peeling.
• Stay on the matt side of the finish scale – Choosing your paint finish can often feel limitless, but for the purposes of painting fresh plaster, it’s best to stick with matt, silk, or eggshell finishes depending on the level of durability and sheen you’re looking for.
• Choose your colour wisely – Lighter shades tend to make rooms feel more spacious and airier, whilst darker tones can create warmth and depth but require more coats for even coverage. If you’re painting a feature, such as a chimney breast, consider the visual impact you want to achieve from the project: are you feeling bright and bold? Dark and brooding?
• Opt for quality whilst helping the planet – Water-based and low VOC paints are thankfully the industry norm these days. Nonetheless, make sure to steer clear of oil-based paints or price points that seem too good to be true. Whilst budget brands can still be effective, higher-quality and even designer paints tend to provide better coverage, last longer, and are often easier to maintain.

Checked all these boxes? Great! Let’s get prepping.

before picking up a brush

To ensure the best finish possible, there are a few key prep steps before getting creative. Whilst they can be time-consuming, and often feel like literally watching paint dry, we promise the result is worth it. Good things come to those that wait!

1.      allow the plaster to dry

Perhaps the most important (and most tedious) part of the job is to wait for your plaster to be dry. And we mean fully dry. If you don’t, cracks and peels are likely to occur, ruining your hard work.

To dry the plaster out for an even paint finish, you should leave it for at least a week, though some plaster can take up to four weeks to completely dry out. As time goes on, you should start to see lighter patches emerge. When the whole wall is of a lighter and consistent appearance (think along the lines of F&B’s Setting Plaster), the surface is ready to go.

2.      smooth your surface

Once dry, inspect the plastered surface for any visible imperfections. Using sandpaper to address particularly rough areas as well as an appropriate filler for any minor cracking or holes, ensure that the plaster is completely smooth and dust free.

3.      (if applicable) create your mist coat

If you’re using one, the next step is to create a mist coat. This is crucial to ensure better adhesion, a smoother finish, and long-lasting results. But first…

what is a mist coat?

Simply put, a mist coat acts as a primer that seals the plaster and helps the topcoat adhere properly. Without it, fresh plaster is likely to absorb moisture from the paint too quickly, leading to a patching, peeling, and uneven finish.

the ideal mist coat cocktail

When making your mist coat, you should aim for a ratio of about 70% paint to 30% water. The specific figures will depend on the thickness of your chosen paint as well as the absorbency of the plastered surface, but 70:30 is a good place to start to ensure sufficient adhesion without sogginess. You can always add more water to the mixture later if required.

Measure your paint into a mixing bucket whilst gradually adding your water. Stir thoroughly until the texture resembles skimmed milk and is slightly translucent. Et voilà– the ideal mist coat! Before committing to the entire wall, you can also test your mist coat on a small, plastered area to check how it dries. You should see some underlying plaster peeking through.

painting new plaster

Now that your surface and paint is prepped, it’s time for the fun part! Perform one last check of the surface, protect your space with drop cloths and apply masking tape to the edges of your wall, and let’s get cracking.

4.      (if applicable) apply your mist coat

Take your pre-prepped mist coat (you’re welcome) and apply the mixture to the wall. Either a paintbrush or roller is fine here. However, if you’re opting for a roller, make sure to keep a paintbrush handy to catch any drips and runs, especially since the mist coat will be a lot thinner than usual paint. Use smooth upward motions until the whole plastered surface is covered, and allow to dry for around 24 hours, or until it is touch dry.

5.      (if applicable) apply your primer

If you’ve opted not to use a mist coat, ensure that you’re using a suitable plaster primer. For new plaster, that’s likely to be a standard water-based plaster primer. For old plaster, a stronger and more specialised choice is probably best.

To apply the primer, use a medium pile roller to apply the product evenly to the surface, working from top to bottom. Don’t forget to cut in with a brush to reach those edges and corners that they roller can’t reach.

Leave the primer to fully dry as directed by your specific product before applying paint.

6.      apply your topcoats

Once your mist coat is dry, you can go about applying your topcoats as normal. There’s no need to sand or clean the surface, as you’ve already covered the prep in the earlier stages.

Ensuring that the bristles of the cutting brush are half covered, carefully cut into the edges of the space. Wipe the brush occasionally to prevent buildup. Then, evenly cover your medium pile roller and apply the paint in an M or W motion to fill the wall. To avoid a framing effect, aim to get your roller as close to the edge of the wall as possible without straying outside the edging lines.

Once your first coat has dried, repeat this process for a second coat, ensuring to keep a smooth motion for even coverage.

final thoughts: how do i paint new plaster?

So, there you have it, a comprehensive guide to painting over new plaster. The addition of a mist coat can lengthen the process, but once you’ve got that covered, you’re onto a winner. Go forth, you plaster painting pro!

Looking for some design inspiration to paint over your plaster? Check out the rest of our painting and decorating blog for more!