Remove mould from window frames and seals

Clean mould off window frames and seals safely, then cut condensation so it doesn't come straight back.

MW-01Open windows and protect the areaOpen the window fully and any others nearby so the room is well ventilated before you start. Lay an old towel or newspaper on the sill to catch drips. Mould spores become airborne once disturbed, so good airflow matters more than usual here.

1 each · Old towel or dust sheet

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MW-02Put on gloves and a maskWear disposable gloves and an FFP2 mask before touching the mould. This stops spores getting on your skin or into your lungs, which matters if you or anyone in the house has asthma or allergies. Skip this step and you can still do the job, but you're more likely to react to it.

1 pack · Disposable gloves (pack)

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1 each · FFP2 face mask

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MW-03Vacuum off loose mould firstRun a vacuum with a brush attachment lightly over the frame and seal to lift loose, dry mould before you use any liquid. This stops you smearing spores around when you wipe. Empty the vacuum bag or canister outside straight after, into an outdoor bin.

1 each · Vacuum cleaner with brush attachment (own)

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MW-04Clean the frame and glass edgesSpray a mould remover onto the frame, following the bottle's dwell time (usually 5-10 minutes) before wiping. For a cheaper option, wipe with undiluted white vinegar instead — it kills most household mould just as well. Wipe with a damp microfibre cloth, working from clean areas towards the worst patches so you don't spread it.

1 bottle · Anti-mould spray (500ml)

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1 bottle · White vinegar (1L)

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1 pack · Microfibre cloths (pack)

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MW-05Get into the rubber or silicone sealMould loves the folds of rubber window seals and the join where sealant meets the frame. Use an old toothbrush or soft-bristle brush dipped in your cleaner to work into these gaps. Go gently — hard scrubbing can tear rubber seals or pull sealant away from the wall.

1 each · Old toothbrush or soft-bristle brush

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MW-06Rinse and dry thoroughlyWipe the whole area over with a clean, damp cloth to remove any leftover cleaner and dead mould. Dry it completely with a fresh, dry cloth. Mould needs damp to come back, so leaving the frame wet undoes most of the work you've just done.

1 each · Dry microfibre cloth

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MW-07Replace sealant if it's stained black throughIf the silicone sealant round the frame is black inside, not just on the surface, cleaning won't shift it and mould will keep coming back. Cut it out with a sealant removal tool, clean the gap, let it dry fully, then run a new bead of mould-resistant sealant. Leave it to cure for the time stated on the tube (usually 24 hours) before it gets wet again.

1 each · Sealant removal tool

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1 cartridge · Mould-resistant sanitary sealant

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1 each · Sealant gun

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MW-08Cut the condensation that caused itMould on a window almost always means condensation, not damp coming from outside. Wipe the frame dry each morning for the next week or two, open a trickle vent or window briefly to air the room daily, and keep the window slightly clear of thick curtains so air can move over it. A £20-30 small dehumidifier in that room overnight makes a real difference if condensation is heavy.

1 each · Small dehumidifier (optional)

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MW-09Tidy up and dispose of wasteBag up used cloths, old sealant offcuts and gloves and put them straight in the outside bin, not left in the room. Wash brushes and any reusable cloths separately from other laundry on a hot wash. Wash your hands well even though you wore gloves.

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