How to Prepare Walls for Painting

Thorough preparation is vital if you want to achieve a professional-looking finish when decorating your walls and ceilings. It's the most important step before you even open a tin of paint.

Knowing how to prepare a room for decorating makes the rest of the job much easier. Different surfaces need to be prepared in different ways. We'll guide you through the process for the different types of surfaces you might encounter. We also have a handy how-to video that walks you through the whole process so that our experts can show you exactly how to get your space ready.

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Preparation

Dust Sheets for floor and furniture

Preparing plastered walls

Preparing painted walls

Removing wallpaper

Cleaning after wallpaper removal

Staying safe

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Clear your room, lay down heavy-duty protective sheets, and wash all surfaces with sugar soap to remove grease and grime.
Fill any cracks with a quick-drying filler, sand everything down to a smooth finish, and use a vacuum to pick up the dust.
Strip away old wallpaper using a scoring knife and hot water, a chemical stripper, or a steam stripping machine.

Planning and protecting your room

So, how do you prepare a room for painting? It all starts with clearing your space.

Move any furniture out of the room, and if you have larger items that you can't remove, group them together in the middle of the room. Cover them securely with dust sheets to protect your floor from dust, debris, and any accidental spills.

Make sure all your surfaces are free from grease, dust, and imperfections. Proper wall preparation for painting means any holes or cracks need to be filled and sanded. You also need to remove any flaky plaster or peeling paint before you begin.

To avoid picking up dust on damp paint later on, use a vacuum to clean any areas where you’ve sanded. The top edge of your skirting board is often a dust trap. When preparing skirting boards for painting, it's best to wipe them down with a damp cloth to make sure they're completely clean.

Staying safe while you work

Always wear protective gloves when you're using filler.

Wear protective gloves and safety goggles when cleaning surfaces with sugar soap.

When sanding, be sure to ventilate the space as best you can. Open your windows and wear a dust mask and safety goggles. This protects you from fine dust particles.

If you plan to use a chemical stripper to remove wallpaper, be sure to read the instructions thoroughly. Wear safety goggles, a dust mask, gloves and protective clothing. Most chemical strippers are caustic. Contact the point of sale if you have any questions or concerns.

How to prepare plastered walls

If your walls are plastered without any wallpaper or paint already on them, follow these steps.

If you're dealing with new plaster, make sure that any fresh plaster has completely dried before you prepare for painting. You can tell it's dry when no dark patches remain.

Priming fresh plaster before painting is key to ensuring a long-lasting finish. Use a specialist paint for new plaster. Make sure to follow the manufacturer's instructions for the number of coats needed.

Alternatively, you can apply two coats of a light-coloured mist coat. This is made up of 60% paint and 40% water to create a watered-down emulsion. This is not necessary if you've primed the wall with specialist paint.

After using specialist paint or the two mist coats, apply two top coats of your chosen colour.

Preparing painted walls for painting

When preparing painted walls for new paint, you need to make sure the surface is smooth and clean.

Firstly, identify any holes, gaps or cracks in the wall.

Use a basecoat to fill in small hairline cracks or minor imperfections.

For larger cracks and holes, start by removing any grease, dust, and flaking plaster from the surrounding area. Wash the edges of the hole with sugar soap. Remember to wear your protective gloves and goggles whilst using this product.

Allow the wall to dry. Then, place some quick-drying filler onto a scraper and work it into the crack or hole. Make sure you fill it completely. Scrape off any excess filler as you go. Follow the manufacturer’s instructions on drying time before continuing.

Once the filler is dry, ventilate the room. Put on your safety goggles and a dust mask.

Use fine-grade sandpaper to sand down the filler until you have a smooth and level surface.

Check the rest of the wall for any areas of flaking paint and sand down where needed.

Thoroughly brush down and vacuum all surfaces after sanding to remove any dust, dirt, and grime.

How to remove wallpaper

Whilst you can paint over wallpaper, the most professional and long-lasting finish is achieved by stripping it. If you're removing wallpaper, bear in mind that scoring the paper is effective for small areas.

A chemical stripper works better for more stubborn areas, with steam removal being the best option when working on a larger area.

To remove small areas of wallpaper, start by lightly scoring the paper with a knife. Take care not to damage the plaster underneath.

Use a sponge and hot water to soak the paper. Leave it to soak for 5 minutes before continuing. This lets the water penetrate the adhesive base.

Scrape off the paper by working your stripping knife into the scores.

Follow the manufacturer's instructions for mixing. Put on safety goggles, a dust mask, gloves, and protective clothing when using this product.

Apply the stripper and allow time for the chemical to soak. Then strip the wallpaper using your stripping knife. Be sure to follow the manufacturer’s instructions throughout this process.

Steam strippers are highly effective when working on a large area.

Start by filling the tank with water. Put on protective gloves and safety goggles, and then switch it on.

Place the steamer pad onto the wallpaper. This allows the steam to penetrate the paper and soften the adhesive. Most steamers take about 15 seconds, but check the instructions on your specific device.

Once the wallpaper has loosened, strip the paper using a stripping knife.

If any area of wallpaper isn't coming away easily, steam it again. Be sure not to leave the steamer pad in one area for too long as it may damage the plaster.

If you need to strip an area of paper that's higher up the wall, use a step ladder. This helps you avoid the hot steam running down your arm. Take care when steaming around switches and sockets. Be sure not to let the water level run low in the steamer, as this can damage the machine.

Once the wallpaper is removed, wash the wall with sugar soap. This removes all traces of grime, dirt and wallpaper adhesive. Then rinse the sugar soap off with warm water and wipe the surfaces down.

Preparing ceilings and specific rooms

If you're asking "How do you prepare a ceiling for painting?", the process is very similar to your walls. Good ceiling painting preparation means checking for cracks, filling them, and sanding them smooth.

You'll want to use an extendable pole for your roller when it comes time to paint. It saves you from constantly moving a ladder around the room

If your ceiling has water damage, follow these steps:

Step 1: clear the damage

Start by removing any flaky plaster, peeling paint, grease, and dust from the affected area.

Step 2: fill the gaps

Wash the edges of any holes with sugar soap, allow it to dry, and then work a quick-drying filler into the cracks or holes using a scraper.

Step 3: sand the area

Once the filler is completely dry, wear a dust mask and safety goggles to sand the area smooth with fine-grade sandpaper.

Step 4: clean the area

Finally, thoroughly brush and vacuum the surface to remove all dust before you start painting.

When you prepare a bathroom for painting, you might find extra grime or moisture build-up on the walls. The same applies for your kitchen walls and ceilings. Sugar soap is brilliant for cutting through this kind of residue. Give your bathroom walls a thorough wash down. Make sure they're completely dry before you start filling or sanding.

Now that your surfaces are clean, smooth, and fully prepared, you're ready for the exciting part. Taking the time to properly prepare for painting makes all the difference, helping you achieve a professional-looking finish that lasts.

You've done part of the hard work, so grab your dust sheets, brushes, and rollers, and enjoy transforming your room. Check out our guide on how to paint a room for the next steps.

FAQs

When using filler or washing walls with sugar soap, make sure you wear protective gloves. You'll also need safety goggles when handling sugar soap. If you're sanding down surfaces, open your windows to ventilate the space and put on a dust mask and goggles. And if you choose to use a chemical or steam stripper for old wallpaper, please read the manufacturer's instructions thoroughly and wear the recommended protective clothing.

Yes, washing your walls is a vital step. Using sugar soap removes grease, dirt, and grime that can stop your new paint from sticking properly. It helps you get a smooth, even finish that lasts much longer.

When preparing skirting boards for painting, it's important to remember that the top edge is often a dust trap. To avoid picking up dust on your damp paint later on, simply use a vacuum to clear the area, and then wipe the skirting board down with a cloth.