How to paint a room yourself: step-by-step guide UK

Painting a room yourself is one of the most cost-effective home improvements you can do. A professional decorator in the UK typically charges between £150 and £300 per room, so doing it yourself can save a significant amount, especially if you have several rooms to tackle. The results can look just as good, provided you take the time to prepare properly.

This guide walks through the process from clearing the room to cutting in the final coat. Follow these steps and you will avoid the most common mistakes that make DIY paint jobs look obviously amateur.

What you will need

Before you start, gather everything in one place. Running to the shop halfway through a coat causes lap marks and uneven drying.

• Emulsion paint (walls and ceiling)
• Primer or mist coat (for new plaster or bare surfaces)
• 9-inch roller with medium-pile sleeve (10mm for smooth walls, 15mm for textured)
• Roller tray and extension pole
• 2.5-inch angled brush for cutting in
• Masking tape (Frog Tape gives cleaner edges than cheap alternatives)
• Dust sheets or old bed sheets
• Sandpaper: 120 grit for filling, 240 grit for final surface prep
• Fine surface filler and a flexible knife
• Sugar soap or a degreasing cleaner

Step 1: Prepare the room

Move furniture to the centre and cover it. Remove curtain poles, picture hooks, and light switch covers if possible. Roll your dust sheets flat across the floor, overlapping at the edges so drips cannot reach the carpet or boards.

Wipe the walls down with sugar soap and warm water. This removes grease, cooking residue, and the thin layer of dust that paint struggles to adhere to. Pay particular attention to areas around light switches, door frames, and anywhere near a cooker. Let the walls dry fully before continuing, at least two hours in a warm room.

Step 2: Fill and sand

Look for cracks, nail holes, and dents. Work fine surface filler into each one with a flexible knife, leaving it slightly proud of the wall surface. Once dry (most fillers need around an hour), sand back with 120 grit until flush. Wipe away dust with a damp cloth.

If you have hairline cracks where the wall meets the ceiling or skirting, a flexible decorator's caulk works better than hard filler. It will not crack again when the building settles.

Step 3: Apply primer or mist coat if needed

New plaster must be mist coated before you apply standard emulsion. Straight emulsion applied to fresh plaster seals the surface unevenly and pulls away as the plaster cures. A mist coat is simply emulsion thinned with water, around 10-20% water by volume. Apply one thin coat and let it dry overnight.

Previously painted walls in good condition can usually be painted straight over, provided you have cleaned them properly.

Step 4: Cut in first

Cutting in means painting the edges, where the walls meet the ceiling, skirting boards, window frames, and door frames, with a brush before you roll the main wall area. Use a 2.5-inch angled brush and apply masking tape to protect any surfaces you want to keep clean.

Work in sections of about a metre at a time. Keep a wet edge as you go. Cutting in and rolling should happen in the same session for each coat, because paint that has dried will show overlap marks under the roller.

Step 5: Roll the walls

Load the roller evenly by working it back and forth in the tray. Apply paint in a rough W or M shape on the wall first, then fill in without lifting the roller. This spreads the paint more evenly than painting in straight stripes.

Work top to bottom, keeping a wet edge at all times. Overlap each pass by about 30% to avoid roller marks. Two thinner coats always look better than one thick one. Thick coats drip, take longer to dry, and often go patchy.

Step 6: Second coat and drying time

Most standard emulsions need at least four hours between coats in normal UK conditions, longer in cold or damp weather. Do not rush this. Applying a second coat over tacky paint drags the first coat and ruins the finish.

Once the second coat is fully dry, carefully remove the masking tape at a 45-degree angle. Do this slowly to avoid pulling paint off the wall.

Common mistakes to avoid

• Skipping wall prep: dirt and grease cause paint to peel within months
• Using cheap brushes: they shed bristles into the paint
• Rolling too fast: it creates foam bubbles in the finish
• Painting in a cold room: below 10 degrees C, most emulsions do not cure properly
• Using the wrong finish: matt is forgiving on imperfect walls, silk shows every bump

How much paint do you need?

A standard 2.5 litre tin of emulsion covers roughly 30-35 square metres per coat. For an average UK room measuring 3.5m x 4m with 2.4m ceilings, you will need approximately 5 litres for two coats on the walls, plus a separate tin for the ceiling. Always buy slightly more than you calculate as you will need touch-up paint later.

Keep any leftover paint in an airtight container, labelled with the room name, brand, and colour reference. Touching up scuffs six months down the line is much easier when you have the exact same paint to hand.