Black spot mould — treat it, don't just cover it
Black spot in corners, behind furniture and around window reveals is condensation finding the coldest surfaces in the room. Paint alone will never solve it, but the right sequence of treatment and coating keeps it away far longer.
Why it grows where it grows
Mould colonises cold spots — thermal bridges at wall junctions, un-insulated reveals, and any surface behind a wardrobe where warm air cannot circulate. The pattern of the growth tells you where the cold bridge is.
- Corners and ceiling junctions
- Window reveals and behind curtains
- External walls hidden by furniture
Kill it, then remove it
A fungicidal wash is applied and left to dwell so it kills the spores rather than smearing them. Only then is the residue removed and the surface allowed to dry fully.
Coating choice after treatment
A fungicidal emulsion or an anti-mould additive gives the new decoration a fighting chance. On chronically cold walls, an insulating-backed lining or thermal wall coating can lift the surface temperature enough to break the cycle.
The habits that keep it away
Trickle vents open, extractors running through the shower and for a while after, furniture pulled a few centimetres off external walls, and drying washing anywhere other than a closed bedroom.
Common questions
Is bleach enough to remove mould before painting?
Household bleach lightens the stain but often leaves living spores in the substrate. We use a proper fungicidal wash with dwell time.
Does anti-mould paint stop condensation?
No — it resists growth on the film, but the condensation itself is a ventilation and heat problem.
Should I redecorate in winter if there's mould?
It can be done, but the surface must be genuinely dry first, which takes longer in cold weather.
Why does it come back in the same spot?
Because the cold bridge is still there. Treating the surface without addressing the temperature difference only buys time.
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Next step
Ask us to survey the affected rooms before you book a full redecoration.
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