How to paint a wall: a step-by-step guide

1. Plan and buy the right amount

Measure the room’s length, width and ceiling height, count the doors and windows, and decide how many coats you need. Two coats is the norm; a third may be needed when covering a strong color. Enter the numbers in the Paint calculator and it gives you liters (or gallons) and a suggested mix of can sizes.

Buy all the paint for one surface from the same batch, or mix the cans together in a bucket before you start (this is called boxing). Small differences between batches show up as patches on a flat wall.

Pick the finish for the room: flat or matt hides imperfections but marks more easily; eggshell and satin wipe clean and suit hallways, kitchens and children’s rooms; semi-gloss is for trim and doors.

2. Gather tools and materials

• Roller frame and a 9 in (23 cm) sleeve: short nap for smooth walls, longer nap for textured walls
• Paint tray or a bucket with a grid, and an extension pole
• Angled brush, 2–2.5 in (50–65 mm), for cutting in
• Painter’s tape, drop cloths or plastic sheeting
• Filler, a putty knife and fine sandpaper (120–180 grit)
• Primer if the surface is new, stained, patched or much darker than the new color
• A damp cloth, a stir stick and a step ladder

3. Prepare the room

Move furniture to the middle of the room and cover it. Cover the floor with drop cloths taped at the edges. Turn off the power at the breaker and remove switch and socket covers, keeping the screws with each plate.

Run painter’s tape along skirting boards, window frames and door casings. Press the edge down firmly with a putty knife or your fingernail so paint cannot creep under it.

4. Repair, sand and clean the walls

Fill nail holes and cracks with filler, slightly overfilling each one because filler shrinks as it dries. Once dry, sand flush with fine sandpaper. Large repairs may need a second thin coat.

Wipe the walls with a damp cloth to remove dust. In kitchens, clean grease off with a mild detergent and rinse; paint does not stick to grease. Let everything dry completely.

Spot-prime every patch. Filler absorbs paint differently from the rest of the wall and will otherwise show through as dull spots (flashing).

5. Prime when it is needed

Primer seals the surface so the topcoat goes on evenly and needs fewer coats. Use it on new drywall or plaster, over large repairs, over water or smoke stains (use a stain-blocking primer), and when going from a dark color to a light one. A wall that is clean, sound and already painted in a similar color usually does not need primer.

On fresh plaster, wait until it has fully dried and lightened in color, which can take several weeks, then use a diluted first coat or a primer made for new plaster.

6. Work in the right order

Paint from the top down so drips land on surfaces you have not painted yet: ceiling first, then walls, then trim and doors. On each wall, cut in first and then roll while the cut-in edges are still wet, so the two blend without visible bands.

7. Cut in the edges

Dip only the first third of the bristles and tap off the excess. Paint a band about 2–3 in (5–8 cm) wide along the ceiling line, the corners and around the tape. Hold the brush like a pencil and let the angled tip guide the line. Work one wall at a time so the edges are still wet when you roll.

8. Roll the walls

Load the roller evenly by rolling it back and forth on the ribbed part of the tray. It should be full but not dripping.

1. Start about one roller width from a corner and roll a large W or M about 3 ft (1 m) square.
2. Without reloading, fill in the shape with parallel vertical strokes.
3. Finish with light top-to-bottom strokes over the whole section to even out the texture.
4. Move to the next section and overlap the wet edge.

Keep a wet edge: always roll from the unpainted area back into paint that is still wet. Do not stop in the middle of a wall; finish it corner to corner. Do not press hard to stretch the paint; reload instead.

9. Let it dry and apply the second coat

Most water-based wall paints are dry to the touch in 1–2 hours and ready to recoat in about 2–4 hours; check the can, because cold and humid rooms take longer. Ventilate the room but avoid strong drafts and direct sun on fresh paint.

Apply the second coat the same way as the first. Between coats, wrap brushes and rollers tightly in plastic so you do not need to wash them.

10. Remove the tape and clean up

Pull the tape off while the last coat is still slightly soft, peeling it back at a low angle. If the paint has hardened, score along the edge with a utility knife first so it does not tear. Touch up small spots with a fine brush.

Wash water-based paint out of tools with water. Do not pour paint down the drain; let leftovers dry out or take them to a waste collection point. Keep a small, well-sealed amount of the color for touch-ups and note the color code on the lid.

Common mistakes

• Skipping primer over patches, which leaves dull spots that show through.
• Letting cut-in edges dry before rolling, which leaves visible bands around the edges.
• Rolling too little paint over too large an area, which gives a thin, patchy coat.
• Recoating too soon: the first coat lifts and the finish becomes streaky.
• Painting in cold or very humid conditions, which slows drying and spoils the finish.

Frequently asked questions