Helpful video reference. The video above is "How to remove mould from a wall or ceiling before painting." from INEXTERIORS Painters & Decorators. It is a practical walk-through of the technique, worth watching for the hand movement rather than just reading about it.
Find out why it is growing
Mould needs moisture. Look at where the patch sits: cold external corners, behind wardrobes, around windows, above shower areas. Those spots are usually cold surfaces meeting damp indoor air, which is condensation, though a leaking pipe, failed sealant or a penetrating damp problem will do the same job.
If the wall is wet to the touch, stained in a tide-mark shape, or the patch keeps growing after cleaning, get the source looked at by a professional. Painting over a leak does not fix it.
Protect yourself and the room
Open the windows, wear a dust mask rated for fine particles, gloves and eye protection, and lay dust sheets. Do not dry brush or scrub hard, because that throws spores into the air.
Kill and clean the growth
Use a fungicidal mould wash made for the job and follow the label. Apply it with a damp cloth or sponge, leave it for the time stated, then wipe the surface clean.
Never mix bleach or any other cleaning product with a mould treatment, as the fumes can be dangerous. Bin the cloths afterwards rather than rinsing them out for reuse.
Let it dry completely
Give the wall several days to dry, longer if the weather is damp and the room is cold. A little heat and a lot of ventilation help. Painting onto a damp surface traps moisture and makes the paint blister.
Seal and repaint
Spot-prime any stained area with a stain-blocking primer so the old marks do not ghost through. Then use a washable or anti-mould emulsion, which is designed for kitchens and bathrooms, in two coats.
Fix the sealant around baths and windows at the same time, and run an extractor fan after showers so the room has a fighting chance.
What this means in Folkestone
Seafront villas and older Georgian streets around the old town often have solid walls and single glazing in places, which makes cold corners and condensation common. Victorian terraces in Cheriton and Morehall tend to suffer in back bedrooms and bathrooms where airflow is poor. Salt-laden sea air also keeps indoor humidity higher in coastal homes, so ventilation matters here more than people expect.
Common mistakes to avoid
- Painting over the patch without cleaning it first or finding the cause.
- Scrubbing dry mould, which spreads spores through the room.
- Repainting before the wall has fully dried, so the coat blisters and the mould returns.
Quick answers
Can I use a mould-resistant paint on its own?
No. It helps once the surface is clean and dry, but it will not hold back a patch that is still being fed by damp.
How big a patch is safe to treat myself?
Small surface patches in a single room are usually a DIY job. Large areas, repeat outbreaks or anyone in the home with breathing problems are good reasons to call someone in.
Prefer we do it?
Room painting from £325, standard trade paint and labour included. See our price guide, our interior decorating page or get a fixed quote.