Cover a water stain on a ceiling

Check the leak is fixed, seal the stain with a stain-blocking primer, then repaint to match.

CS-01Confirm the leak causing the stain is actually fixedPainting over a wet or active leak just hides the problem and the stain will come back through, often within weeks. If the stain is damp to the touch, soft, or has grown recently, find and fix the source first - a bath overflow, a roof leak, or a pipe upstairs. Only move on once the area has been dry for at least a few days.

CS-02Protect the roomMove furniture out of the way or into the middle of the room and cover it with a dust sheet. Lay dust sheets over the floor under the stained area, since primer and emulsion drip more than you expect off a roller on a ceiling.

2 each · Dust sheet

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CS-03Clean the stained areaWipe the stain and the surrounding ceiling with sugar soap solution on a damp sponge to remove grease, dust and any loose surface dirt. Let it dry fully before you do anything else - painting over a damp patch traps moisture and the stain can bleed straight through.

1 bottle · Sugar soap

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1 each · Cloth or sponge

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CS-04Scrape off any flaking or bubbled paintWater stains sometimes lift or blister the existing paint or paper. Use a scraper to remove any loose flakes back to a firm edge, then lightly sand the area with fine sandpaper so it's smooth and level with the surrounding ceiling. Wipe away the dust with a dry cloth.

1 each · Scraper

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1 each · Fine sanding sponge

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CS-05Apply a stain-blocking primerOrdinary emulsion won't stop a water stain showing through - you need a proper stain-blocking primer, either an aerosol for small marks or a brush-on tin for larger areas. Cover the stain itself plus about 100mm beyond it in every direction, so the primer edge doesn't show as a ring once you repaint.

1 can · Stain-blocking primer (aerosol, 400ml)

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1 tin · Stain-blocking primer (tin, 750ml)

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CS-06Let the primer dry fullyCheck the tin or can for drying time - most need at least an hour, some longer in a cold or unventilated room. Don't rush this step; painting over primer that hasn't cured properly can drag it and leave a patchy finish.

CS-07Repaint the ceiling to matchFor a small, isolated patch, feather the emulsion out well beyond the primed area so the edge blends in rather than showing as a flat patch under changing light. If the existing ceiling colour has yellowed or the paint is old, you'll get a better match painting the whole ceiling in one go rather than just the patch.

1 tin · Ceiling emulsion (matching shade, 2.5L)

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1 set · Roller sleeve and tray

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1 roll · Masking tape

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CS-08Apply a second coat and check the finishOnce the first coat is dry, check from a few angles and under a lamp - stain-block primer can still show a faint shadow through a single coat. Apply a second coat of emulsion if needed, letting it dry fully before moving furniture back.

CS-09Clean upWash brushes and rollers straight away in warm water while the paint is still wet, or bin foam rollers if they're too far gone to save. Fold dust sheets carefully to keep any drips contained, and check the floor for splashes before you leave the room.

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