Painting Window Sills: A Step-By-Step Guide For Interiors

Painting your window sills can be a simple and rewarding task. It's a great way to give your room a fresh new look, especially if you're finishing up a room renovation and want everything to fit together. Window sills can get damaged from sun, rain, and condensation, so they may need a fresh coat of paint every once in a while. It's also a good idea to paint your window sills if you're preparing your house for sale, as it shows you've taken good care of your home. Here's a step-by-step guide to help you get started on painting your window sills like a pro!

Prepare the area: remove furniture, lay a dust sheet, and tape the area

To prepare the area for painting your window sill, you should start by removing any furniture or decor from the room. This will ensure that your belongings are not damaged and that you have enough space to work in. If there are any curtains or blinds, take them down, and open the window slightly so that you don't accidentally paint the window shut.

Next, you'll want to lay down a dust sheet to protect the floor from paint stains and dust. A drop cloth or a large sheet of plastic sheeting will do the trick. Make sure it's secured in place with tape. This will also protect the windows and wall around the window sill and frame.

Now it's time to tape the area. Use painter's tape or UV masking tape to secure the dust sheet and protect the surrounding area. This will help you paint quickly and achieve clean lines.

Sand the wood and apply paint stripper

Sanding and applying paint stripper are two different methods for removing paint from wood surfaces. Sanding is a good option if you plan to paint over the surface again. In this case, you only need to sand enough to create a rough surface that the new paint can adhere to. Use a handheld sander or sanding block with 180-grit sandpaper until the paint becomes dull. If you need to remove paint globs, use coarser 80-grit sandpaper. Once the shiny top layer of paint is gone, wipe away the dust and you can begin priming and painting.

However, if your goal is to expose the wood grain underneath or stain the surface, you will need to remove every last drop of old paint, and sanding is not the best method for this. Instead, you should use a paint stripper.

Paint strippers are solvents that soften old paint for easy removal. They are available as liquids, gels, or pastes and are effective for large projects, curved shapes, and fine details. They can be messy and smelly, so it is recommended to use them outdoors or in a well-ventilated area with drop cloths.

• Put on protective gloves and a face mask.
• Pour a small amount of the paint stripper into a glass or metal container.
• Apply the paint stripper to a small section of the surface using a paintbrush, following the manufacturer's instructions.
• Allow the paint stripper to sit until the paint begins to crack and bubble.
• Use a plastic or metal scraper to scrape away the bubbling paint. Work on small sections at a time and tackle the paint when it is bubbling to prevent it from drying and readhering to the surface.
• Reapply the paint stripper as needed, especially for detailed or problematic areas.
• Once you've removed as much paint as possible, apply mineral spirits with a rag or paper towel and scrub off any remaining paint with steel wool.
• Finally, clean the surface with mineral spirits to remove any residual stripper from the wood.

After stripping the paint, you can refinish the wood as desired.

Prime the window sill

To prime a window sill, you will need to prepare the area first. Remove any furniture or decor from the room to avoid obstruction and damage. Take down curtains and blinds, and lay a dust sheet down to protect the floor from paint stains. Secure the dust sheet with UV masking tape to protect the windows and wall around the window sill and frame.

Next, sand the wood with fine sandpaper to create a smooth, matt surface ready for painting. Sand in gentle, circular motions to remove old paint and imperfections. After sanding, clean away any dust with a microfibre cloth.

Now it's time to repair any holes or cracks in the woodwork using filler. Once the filler has cured, sand and clean the surface again.

The key to painting a window sill smoothly is to apply a high-performing primer. Use a stain block primer to prevent sap or contaminants from spoiling the wood and paintwork. For detail areas, use an angled gloss brush to apply the primer. For larger, flat areas, use a woodwork gloss roller to speed up the process. Remember to clean your brushes with white spirit after priming.

Before applying the top coat, give the primed surface a quick, light sand to remove any brush marks and to achieve a smoother, more professional finish. Clean the area with a microfibre cloth to remove any dust.

Clean the primer and paint the surface

Now that you've primed the window sill, it's time to clean the primed surface and apply the top coat of paint. This step will ensure a smooth and professional-looking finish.

First, use some fine sandpaper to lightly sand the primed surface. This will help remove any brush marks from the priming stage and give a smoother finish. Be sure to sand in gentle, circular motions, and wear protective gloves and eyewear if necessary. Once you're done sanding, use a microfibre cloth to wipe away any dust.

Next, you'll want to repeat the painting process. Use an angled brush for any detailed areas and a small roller for the flat surfaces of the window sill. Apply thin coats of paint with back-and-forth strokes for a consistent finish. If you're using a roller, be sure not to overload it—thin coats are better.

Finally, clean your brushes and rollers using white spirit to remove the paint. For brushes, work the white spirit into the bristles and then wipe away the excess paint with paper towels. For rollers, wrap them in cling film to keep them moist and reusable for the next 48 hours.

Seal the window sill

Sealing your window sill is the final step in painting your window sill and will ensure that your hard work is protected. This is especially important if you know your window sill will take a beating or if you used chalk paint.

If you used chalk paint, or if you know your window sill will take a lot of wear and tear, you should use a heavy-duty furniture-style sealer to finish things off. Even if you don't think anything will touch your newly painted window sill, an open window lets everything outside come in and sit right on the sill.

Many chalk painters like to pair their finished project with wax. If you insist on using wax, make sure you apply enough coats and then buff to give a shiny finish that is easy to wipe clean when needed. You will probably need to re-wax every so often to keep the barrier up, which is why some prefer a furniture sealer instead.

If you are using a sealer, make sure you follow the manufacturer's instructions and allow enough time for the product to dry and cure.

Frequently asked questions