Why does my touch-up patch show as a different sheen?

Touching up is the most reliably disappointing job in decorating, and people blame the paint. The paint is usually fine. The wall around the patch is not the surface it was on the day it was painted, and the way you are applying the touch-up is not the way the wall was applied — and both of those are visible in raking light even when the colour match is exact.

Step by step

1. Understand the three differences before you start.Film thickness: a dabbed touch-up is heavy in the middle and feathers to nothing, so it stands proud and shadows. Texture: the wall has roller stipple, the patch has brush marks, and the two scatter light differently. Sheen: emulsion continues to cure and to collect a fine film of dirt for months, so it is very slightly duller than the same paint straight from the tin.
2. Use the same paint, properly stirred, from the same batch.Colour drift between batches is real. If you have the original tin, stir it thoroughly from the bottom before use — settled pigment gives a genuinely different shade. If you have to buy new, expect a slight difference even from a scan match.
3. Apply it with a small roller, not a brush.A 100mm roller with the same nap as the original gives the same stipple as the surrounding wall, which removes the texture difference entirely. This single change does more than anything else.
4. Apply it thin, and feather well beyond the damage.Load the roller lightly and work outwards from the repair, using progressively lighter pressure at the edges so the film tapers rather than stopping. A larger, thinner, feathered patch is far less visible than a small thick one.
5. Prime any repair before touching in.Bare filler and bare plaster have completely different suction from the painted wall, so paint over them dries to a dull patch regardless of technique. Spot-prime or mist the repair, let it dry, and then touch in.
6. Judge it the following day, in raking light.Wet paint always looks different. Let it dry fully, then hold a light flat against the wall. If it still shows, the honest answer is the next step.
7. Repaint corner to corner when it matters.A full wall, edge to edge, removes all three differences at once. On a visible wall in a main room this is the reliable answer, and it is why decorators quote by the wall rather than by the patch.

Tips

• Touch-ups work far better on flat matt than on anything with sheen. On silk, a touch-up essentially never disappears, and repainting the wall is the only real option.
• The best time to touch up is soon after the original job, before the wall has cured and dirtied. A patch done a month later disappears far more readily than one done three years later.
• Keep a labelled jar of each room's paint rather than the big tin — a small container full to the top keeps for years and is what you will actually reach for.

Common mistakes

• Dabbing a touch-up on with a brush — It leaves brush texture in a rolled surface and a thick spot in an even film. Both are visible in any light that rakes across the wall.
• Touching in over unprimed filler — The repair has far higher suction, so the paint sinks in and dries dull. It reads as a flat spot in the wall however good the colour match.
• Using a freshly bought tin scanned to match — A scan match gets the colour close but not exact, and it will not match the sheen of a wall that has aged. Use the original paint if it exists.

If it doesn't work

Questions people ask