Fix patchy paint — HomeGraft

Work out why paint looks patchy, then reseal, mix and repaint evenly so the finish matches across the whole wall.

FP-01Work out why the patches are showingLook at the wall from an angle in daylight and with a lamp at night — patchiness often only shows under raking light. Check whether the flat, dull patches sit over filler, new plaster, or old repairs, since these soak up paint differently to the rest of the wall. Also check if the last coat was applied with a different roller or from a different tin — sheen and colour can vary between batches.

FP-02Get matching paint and the right rollerBuy paint in the same finish (matt, silk, satin) and ideally the same batch number as the original, printed on the tin base. If you can't match the batch, plan to repaint the whole wall rather than just the patch, or the new paint will show as a slightly different tone. Use a roller with the same nap length as before — a mix of nap types across one wall causes texture differences that read as patchiness.

1 2.5L tin · Matching emulsion paint

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1 each · Medium-pile roller sleeve

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FP-03Protect the roomLay dust sheets along the skirting and floor below the wall. Move furniture clear or cover it. Take down any pictures or wall fixings you can, and tape off socket faceplates and switches with low-tack masking tape.

1 each · Dust sheet

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1 roll · Low-tack masking tape

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FP-04Wash the wallWipe the whole wall with sugar soap solution on a damp sponge to remove dust, grease and finger marks — these are a common cause of patchy drying. Rinse with clean water on a separate sponge and let the wall dry fully before you touch it again.

1 bottle · Sugar soap

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2 each · Sponge

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FP-05Fill and sand any small marksFill dents, nail holes or hairline cracks with a light filler, pushing it flat with a filling knife. Once dry, sand smooth with fine sandpaper so the surface is level — bumps and dips catch the light and look like patchy paint even when the colour is even.

1 330g tub · Ready-mixed filler

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1 pack · Fine sandpaper (P150)

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FP-06Seal porous patches before paintingFiller, fresh plaster and bare plasterboard all soak up paint faster than the surrounding wall, leaving a flat, dull patch even after a full coat. Seal these areas first with a mist coat — ordinary emulsion thinned about 10% with water — or a proper wall primer, and let it dry fully. Skipping this step is the single biggest cause of patchy-looking repairs.

1 1L tin · Wall primer/sealer

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FP-07Stir the paint properlyStir the paint from the bottom up with a flat stick until it's fully mixed — pigment settles at the bottom of the tin and uneven mixing causes blotchy colour. Don't shake the tin, as this introduces air bubbles that can show as tiny flat spots once dry.

1 each · Paint stirring stick

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FP-08Apply the first full coatLoad the roller evenly and work in a consistent pattern — up, down, then a light pass to blend — across the whole wall, not just the patchy area. Keep a wet edge by working into the previous section before it starts to dry, since going back over half-dried paint is what causes streaky, patchy results. Paint the whole wall in one session where possible.

1 each · Paint tray

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1 each · Extension pole

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FP-09Check under different light and let it dry fullyLet the coat dry for the time stated on the tin — usually 2 to 4 hours to touch, but longer before a second coat. Check the wall again in daylight and under artificial light for any patches, flat spots or colour differences. Most emulsions need a genuine drying time before the true colour and sheen show, so don't judge it while still damp.

FP-10Apply a second coat if neededMost walls need two full coats for an even finish, especially over patched or previously patchy areas. Apply the second coat using the same rolling pattern as before, working the full wall again rather than just touching in patches, which is what causes visible edges.

FP-11Clean upWash rollers and brushes in water until it runs clear, then stand them on their end to dry. Reseal the paint tin and store it somewhere frost-free for future touch-ups. Remove masking tape while the paint is still slightly soft to avoid pulling off flakes, and lift dust sheets once the wall is dry to touch.

1 bottle · Washing-up liquid

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