Landlord painted over mould? The honest answer
If your landlord painted over mould, the paint has sealed the growth in rather than removed it. No mould spray can reach mould under a paint film, so it comes back through. The lasting fix is to strip back the affected paint, treat the wall, let it dry, prime and repaint, and deal with the damp causing it.
It is one of the most common complaints from renters: the landlord painted over the mould, it came back through, and now mould remover does not seem to work.
The mould remover probably did work, on the bit it could touch. The problem is the part it cannot touch. Spray sits on top of the new paint. The mould that was there before is underneath, still alive, still sitting on a damp wall, and pushing its stain up through every coat.
That does not mean you are stuck. It means the job has to be done in the right order, and if you rent, it probably should not be you doing most of it.
Why mould comes back through paint
The moisture is still there
Mould grows where a wall stays damp. Paint does nothing about condensation, poor ventilation or a leak.
Live growth under the film
Paint traps the mould against the wall. It keeps growing behind the film and finds its way back out.
Stains bleed through
Mould staining soaks through ordinary emulsion, which is why grey shadows appear within weeks.
Painting over mould is a bit like putting a plaster on a splinter. It looks better for a while. The thing causing the problem is still in there. Mould comes back unless the moisture causing it is fixed, and painting over it adds a second problem: now there is a layer between your mould remover and the mould.
How to tell if mould has been painted over
Fresh paint can hide mould for a few weeks. These are the giveaways:
- Dark patches showing through. Grey, brown or black shadows appearing under new paint, often in the corners of a ceiling, behind furniture or around a window.
- Bubbling, flaking or peeling paint. Paint struggles to stick to a damp, mouldy surface, so it lifts.
- A musty smell in one area. If one corner of a room smells damp even though it looks clean, something is growing.
- History. If you saw mould in that spot at a viewing, or a previous tenant mentioned it, and it was redecorated just before you moved in, that is worth noting down.
Take photos now
Photograph the wall with the date visible on your phone, and again every week or two. A clear timeline is useful whether you are a renter reporting it, or a landlord showing what has been done.How to treat painted over mould properly, step by step
For a small patch, this is a manageable job. For large areas, or mould that comes back however often you treat it, get a professional to look at the cause. A professional mould removal specialist can find where the moisture is coming from.
- 01
Protect yourself and the room
Wear gloves, eye protection and a well fitting dust mask. Open a window, move furniture away and lay a dust sheet. Keep children and pets out while you scrape. - 02
Treat the surface first
Spray the visible mould with a mould remover before you disturb it, and wipe it off. This deals with surface growth so you are not spreading it about when you start scraping. - 03
Scrape or sand back the affected paint
Where mould keeps coming through, the paint over it has to come off. Wet the surface first to keep the dust down, then scrape or sand carefully. Do not dry sand mouldy paint. Wipe up and bag the debris as you go. - 04
Treat the exposed wall and let it work for 10 minutes
Spray the bare surface with a mould remover spray, leave it 10 minutes, then wipe it clean. Treat a little way past the visible edge. - 05
Let it dry fully
Do not rush this. Ventilate the room and give the wall time to dry right through. Painting a damp wall is how the problem started. - 06
Prime with a stain block, then repaint
A stain block primer stops old marks bleeding through. Then repaint, with anti-mould paint if you like. It slows regrowth on a clean, dry wall, but painting over live mould does not stop it. - 07
Fix the moisture
Without this step, everything above is temporary. Improve ventilation, run extractor fans, dry washing outdoors or with a vent, and get leaks and cold spots looked at.
For more detail on the treatment side, read our guide on how to get rid of mould on walls permanently, and on choosing a mould remover for painted walls.
Renting? What to do when your landlord painted over the mould
Here is the important bit for tenants: you usually should not be the one scraping walls. Damp and mould caused by the building, such as condensation from poor ventilation, a cold wall or a leak, is normally for the landlord to put right. Painting over it is not putting it right.
Report it in writing
Email or message your landlord or letting agent. Say where the mould is, that it has come back through paint, and ask them to fix the cause, not just redecorate. Keep a copy.
Photos and dates
Attach dated photos. Note when you first reported it, every reply, and every time it came back. A simple timeline is hard to argue with.
Social housing in England
Social landlords in England must act on damp and mould hazards under Awaab’s Law. Read more in our COSHH and Awaab’s Law guide.
Private renters
If your landlord does not act, contact your local council’s environmental health team. They can inspect the property and require repairs.
Can I clean it myself in the meantime?
Yes. Keeping the surface clean is sensible while you wait, especially in a bedroom. Wiping surface mould is fine; it is the scraping, sanding and repainting that should be your landlord’s job. Use something that will not damage the decor. Bleach can strip and blotch paint, which can turn into an argument at the end of a tenancy. A paint safe, pH neutral spray like Mould Check is safe on painted walls and wallpaper and gives off no harsh fumes, so it is fine to use with children and pets at home. Just remember it is keeping on top of the problem, not fixing it.
Landlords: why painting over mould is a false economy
Painting over mould is quick, cheap and looks fine at check in. Then it comes back, often within weeks, and you are dealing with a tenant complaint, a second visit, another repaint, and a trail of messages showing the problem was covered rather than fixed. For social landlords in England, that trail matters even more under Awaab’s Law.
Doing it properly once is cheaper than doing it badly three times:
- Find and fix the moisture source: ventilation, extractor fans, insulation, leaks.
- Remove mouldy paint where growth keeps coming through, using a wet method to keep dust down.
- Treat the wall, let it dry fully, use a stain block primer, then repaint.
- Record what you did, with photos and dates.
If your tenants are at home while the work is done, a COSHH free spray means no COSHH risk assessment for the product and no need to move people out for the treatment itself. Mould Check is used by the NHS and Clarion Housing. See the Mould Check mould remover spray for sizes, including 5L and 10L refills for maintenance teams.
Need a full remediation? Find a mould specialistQuestions people ask about painted over mould
You can only clean what is on the surface. A mould remover spray will deal with growth that has come back through the new paint, but nothing can reach mould sealed under the paint film, so it will keep returning. The lasting fix is to scrape back the affected paint, treat the wall underneath, let it dry, prime and repaint, and fix the moisture causing it. If you rent, that is usually your landlord’s job: tell them in writing with photos and dates.
Because the cause is still there. Mould grows where a surface stays damp, usually from condensation on a cold wall, poor ventilation or a leak. If the moisture is not fixed, or the mould was painted over rather than removed, it grows back in the same spot. No product stops mould permanently on its own.
Not if you want it to stay gone. Paint seals live growth and moisture under a film, and the mould and its stain come back through. Treat the mould, scrape back any affected paint, let the wall dry completely, then use a stain block primer before you repaint.
It helps. Anti-mould paint slows regrowth on a clean, dry, treated wall. It does not kill mould that is already underneath it, and it will not cope with a wall that stays wet. Painting anti-mould paint over live mould does not stop it.
Bleach-based sprays can strip or discolour paint. Mould Check is hypochlorous acid at pH 6 to 7, not bleach, so it does not strip paint or colour the way bleach does. It is safe on painted walls, ceilings and wallpaper. Spray, leave 10 minutes and wipe clean.