Is your home at risk of mould? Top warning signs to watch for

Mould is a nightmare for homeowners and tenants alike, creeping into homes and causing damage to walls, ceilings, and even your health. The key to stopping it? Spotting a warning sign of mould before it gets out of hand. Mould thrives in damp, poorly ventilated spaces, and once it takes hold, it can spread rapidly. Here’s what to watch for and what you can do about it.

1. Musty smell that won’t go away

That damp, musty smell lingering in certain rooms? It’s often the first warning sign of mould. Even if you can’t see it, hidden mould could be growing behind walls, under carpets, or in loft spaces. Pay attention to areas with poor ventilation, like bathrooms and basements.

2. Black, green, or white spots on walls and ceilings

Visible mould patches, especially in bathrooms, kitchens, or bedrooms, are a clear red flag. Small black specks often indicate early growth, while larger green or white patches mean mould is already well established. Mould often appears near windows, skirting boards, or on ceilings where condensation builds up.

3. Peeling wallpaper or bubbling paint

Moisture trapped behind walls can lead to peeling wallpaper or bubbling paint. If you notice this happening, check for condensation or leaks that could be feeding mould. Pay close attention to exterior walls and areas around windows where damp can accumulate.

4. Persistent condensation on windows

Excess moisture leads to condensation, and where there’s condensation, mould is never far behind. If your windows are constantly wet, take action to improve ventilation by opening windows, using extractor fans, or investing in a dehumidifier.

5. Unexplained health issues

Coughing, sneezing, or worsening asthma? Mould spores in the air can trigger allergies and respiratory problems. If you notice symptoms at home but feel better elsewhere, mould could be to blame. Children, the elderly, and those with pre-existing conditions are particularly vulnerable.

6. Damp patches on walls, ceilings, or floors

If you see damp stains on walls or ceilings, it’s a big warning sign of mould. These patches can appear brown, yellow, or even grey and often indicate a water leak or condensation issue. Left untreated, these damp areas will soon develop mould growth.

7. A cold, clammy feel in certain rooms

Does one part of your home always feel damp or cold, even when the heating is on? This could mean poor insulation or trapped moisture, both of which create the perfect conditions for mould growth.

8. Leaks or water ingress

Leaking roofs, pipes, or even small drips under sinks can lead to mould problems. Check under sinks, behind appliances, and in loft spaces for signs of leaks. Catching and fixing leaks early can prevent bigger problems down the line.

What to do next

If you spot any warning sign of mould, act fast:

• Improve ventilation by opening windows and using extractor fans.
• Control humidity with a dehumidifier to reduce excess moisture.
• Fix leaks to remove the source of dampness.
• Use specialist mould removers to clean affected areas properly.

If mould keeps returning or covers a large area, professional mould removal may be necessary. Don’t ignore the signs—early action can save you time, money, and your health.