how to repaint a window sill (indoor and outdoor)

It’s fair to say that it’s the finishing touches that truly make a room stand out. Amidst all the candidates for these final embellishments, the humble window sill often goes overlooked. Yet, refreshing your window sills can work wonders, adding subtle charm and rejuvenating the entire space. Whether indoors or outdoors, the window sill serves as a potential focal point, framing views and inviting natural light. In this guide, we’ll show you exactly how to repaint a window sill, unveiling the transformative power of this often underrated finishing touch.

rethinking your window sills

Like we mentioned, window sills are seriously sold short in the home interior world. Beyond collecting dust or acting as a haphazard space to put trinkets, have you ever put much thought into them? Probably not.

The simple truth is that window sills are criminally underrated. And they deserve a little more attention for their raw potential, not just as an extra few inches of storage, but as a design feature in their own right.

Your cogs are likely whirring now. Maybe you’re envisioning adding an assortment of specially curated ornaments, creating a window side desk setup, or perhaps even a seating area. And to pull any of these off you need a solid colour scheme, which is where we can get creative…

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curating a window sill colour scheme

While many may default to the classic choices of white, grey, or natural wood for window sills, the truth is, the possibilities are endless. With a little imagination, you can turn an afterthought into a showstopper. So don’t be afraid to step outside the conventional palette and inject personality into your space with bold hues or subtle tints.

From colour drenching the space – window sills included – to making graphic window sill colours pop against neutrals or simply complementing your doors and skirting, there are plenty of ways to create a professional, magazine-worthy finish.

But don’t just take our word for it: take a look at this beautifully sophisticated joinery and window sill combo in Sulking Room Pink from Farrow and Ball. Breathtaking, right?

Yep, it’s without a doubt that the right colour combinations can pull everything together. Just make sure you get to grips with your shade before you get to work. Ordering sample pots of different hues will allow you to test how the light interacts with each paint throughout the day, ensuring you find the perfect match for your aesthetic and lighting conditions.

what’s the best paint for window sills?

If you’re wondering about what paint to use on your window sills, here’s a quick explainer.

First of all, paint type and application. Water-based paint is your best bet for a more professional finish as, unlike oil-based equivalents, it is quicker and easier to apply. It also has the benefit of being a lower-impact paint in terms of the planet, so you can renovate your home with complete peace of mind.

On top of the paint’s composition and environmental credentials, you need to think about the materials you are painting. Usually, window sills are wooden, but you might find that you end up painting stone, concrete, uPVC or masonry – and each requires a paint that is up for the job

For quality window and joinery paint brands to use on indoor window sills, we suggest opting for Zinsser, Bradite or Dulux if you’re after a trade paint. These high-performing paints will do the job well. Plus, you can get them mixed to any colour, including your favourite Little Greene shade.

For those who find themselves feeling a little fancy, you might want to look at a more high-end option such as Farrow and Ball, which come in a variety of different finishes from silky mid-sheens to ultra-matt sophistication. As the paint finish will affect the durability and overall appearance of your window sills, don’t neglect to do your homework!

Finally, consider choosing a self-priming paint. This way you won’t have to faff around with two products, and you can get to the painting much quicker.

the tools you’ll need to paint your window sills

Before we get to the painting process, make sure you’ve gathered all of your tools and equipment.

• Reusable dust sheets to keep things tidy
• Sugar soap or clean spirit, bucket of water and cloth
• Sandpaper of varying grits and putty knife / scraper
• Sealant (if required) and stain blocker (for certain types of wood)
• Painters masking tape
• The correct paint, primer and tray
• Paint brush or mini roller

Anything missing? Don’t worry – we stock most of these, and we’ll deliver them in biodegradable packaging right to your door.

how to paint indoor and outdoor window sills

Now we’re ready to take the creative leap with our paint colours, it’s time to get down to business. Here’s how to repaint a window sill in 6 steps.

1)      get everything ready

Before you get started with painting your window sills, better clear the space by either moving or removing any furniture. Also, don’t forget to cover any furniture left in the room with dust sheets and spread some more covering under the window sills you plan to paint.

If you’re planning to paint exterior window sills, make sure there is plenty of space to work in, and leave some room for a ladder if you need to paint first-floor window sills.

2)      start the prep

First, scrape off any peeling paint with a scraper or a wire brush if you’re doing it outside. Then use some rough sandpaper to even out the bumps and lumps in the old colour if there are any.

For outdoor windows, you may need to give it a stronger clean in the case of fungi, algae and moss, using a fungicidal product or jet washer, and you don’t need to sand it beyond getting the initial grime and paint off nice and smooth.

For wooden sills, however, you’ll need to do a bit more sanding. To get a smooth finish, use some finer sandpaper with a grit of 180-220.

Note: only use your scraper to remove loose paint – it’s not a great idea to force it all off this way, particularly if you are working with uPVC windows. In this instance, take care with the process, ensuring you sand lightly before application.

3)      fill in any gaps and cracks

Now, identify any gaps or cracks in the sill that need to be filled. Once you’ve located them, choose an appropriate interior or exterior filler to use. Follow the instructions on the filler product label to ensure you apply it correctly. Once the filler has been applied, allow it to dry completely. This can take several hours, so be patient.

After the filler has dried, use sandpaper to smooth it down until it is flush with the surface of the sill. Ensure that you remove any excess filler to avoid any inconsistencies in the final finish. Once you’re satisfied that the surface is smooth, use a brush or vacuum cleaner to get rid of any dust or debris that may have accumulated.

Then, use a damp cloth to wipe down the entire sill with your clean spirit or sugar soap. This will help to remove any remaining dust or debris and leave the surface clean and ready for any further treatment. Remember to allow the sill to dry completely before continuing with any further work.

4)      mask up

With most of the prep out of the way, you can cover the edges you don’t want to paint with masking tape. If you’re painting outside, it’s a good idea to cover the wall too so you don’t accidentally get paint on it.

5)      get priming

Working with a window sill that’s previously painted or using a self-priming paint? Then you can skip straight on to the next step!

If you’re painting bare wood, slap on a wood primer first. Same goes for bare masonry or concrete – use an appropriate primer. Start by cutting in with a brush, painting along the inside edge first, then work your way outwards. Finish by painting the front of the sill with the primer. Let it dry, then give it a light rub down with a fine-grade sandpaper. Finally, wipe the surface with a damp cloth to clean it.

6)      begin painting

Alright, now it’s time to do the next step. Just do the same thing as before with the brush and add the top coat. Start by making an edge around the sill with the brush first. Then fill in the gaps with a 4-inch roller or an angled brush if you prefer it. Don’t put too much paint on the roller, thin coats work better. Once you’re done, give it a light rub down again and wait for the paint to dry as suggested by the manufacturer. After that, you can add another top coat to finish it up.

7)      wrap things up

With all of the previous steps complete, all that’s left is to tidy up and let your newly painted window sills dry. If you or anyone else in your home is likely to forget about the damp paint, you can stick a notice next to it.

Clear away all of the tools and materials and start cleaning up. When washing your brushes and rollers, try to use a planet-friendly alternative to white spirit and don’t forget to recycle any leftover paint.

Et voila! Everything you could possibly want to know about how to repaint a window sill.

do I need to prime window sills before painting?

When it comes to painting interior wooden window sills, you will only need to apply a primer if the sills are made of bare wood. A good quality primer will help to hide any knots, grains, or discolorations in the wood, leaving a smooth and even surface for painting. If the sills have already been painted or varnished or you have a self-priming product, you can skip the primer step and proceed straight to painting.

Similarly, if you want to paint exterior concrete, wood or masonry sills, you will need to use a primer undercoat. This is especially important if the sills have not been painted before. A good-quality exterior primer will help to seal and protect the surface from moisture, cracking, and other weather-related damage. It will also provide a good base for the topcoat of paint, ensuring that the colour stays vibrant and lasts long.

When choosing a primer, make sure to pick one that is compatible with the type of surface you are painting and that is suitable for outdoor use.

is there any difference in the process between indoor and outdoor window sills?

While the basic process of repainting window sills remains similar for indoor and outdoor surfaces, there are key differences to consider.

Outdoor sills often require a more thorough cleaning and surface preparation due to exposure to harsh weather conditions. And crucially, these outdoor surfaces may benefit from specialised primers for added protection against moisture and UV rays – like this stabilising primer, designed to seal and bind the surface.

Timing is also crucial when painting outdoors, with thought needing to be given to weather conditions for optimal paint adhesion and finish. Sealing and regular maintenance are also more essential for preserving the appearance and integrity of outdoor window sills over time compared to their indoor counterparts.

nail your window makeover the first time round

Whether you opt for a soft pastel, a rich jewel tone, or a vibrant pop of colour, repainting your window sills presents an opportunity to express your unique style and elevate the ambience of your home.

If you’re of the opinion that white window sills are a bit of a cop-out – let us know what colour(s) you pick! And if you stay true to a classic white tone, which one did you choose? We’re keen to see your creations, so don’t hesitate to tag us on social media.

Got a hankering for more DIY tutorials? Don’t worry we have plenty more on our blog.