How to Get Rid of Mould in Your HDB Flat for Good

Mould is an almost universal battle in Singapore homes — our year-round humidity gives it exactly the damp, warm conditions it loves. A quick wipe removes the surface growth, but if it keeps returning, the mould is telling you about an underlying moisture problem that cleaning alone won’t solve. This guide covers how to get rid of mould in your HDB flat safely, and — more importantly — how to stop it coming back.

Key takeaways

Clean surface mould, but find and fix the moisture source or it returns.
Common sources: poor ventilation, condensation, and waterproofing or plumbing leaks.
Improve airflow and keep humid areas dry.
Mould that keeps coming back in one spot signals a hidden leak.

Cleaning mould safely

For small areas of surface mould on tiles, grout or painted walls, you can usually clean it yourself. Ventilate the room, wear gloves and ideally a mask, and use a mould-specific cleaner or a diluted solution suited to the surface, letting it dwell before wiping. Avoid dry-brushing mould, which spreads spores into the air. For hard, non-porous surfaces this often does the job. What it won’t do is fix why the mould appeared.

Why mould keeps coming back

If mould returns in the same spot after cleaning, there’s a moisture source feeding it. Common culprits in HDB flats include poor ventilation in bathrooms and kitchens; condensation on cool surfaces; a waterproofing failure letting damp into walls and floors; and leaks from plumbing or an inter-floor leak from the unit above. Until the moisture source is addressed, the mould will keep coming back no matter how often you clean it.

The common trouble spots

Recurring mould at bathroom corners and skirting often points to a failing floor membrane. Black mould along window frames and cool walls usually indicates condensation and poor ventilation. Mould behind or beneath cabinetry can signal a slow plumbing leak. And a ceiling stain with mould is very likely an inter-floor leak. Matching the location to the likely cause helps you fix the right thing.

Preventing mould long term

Ventilate — run exhaust fans in bathrooms and kitchens, and open windows to let humidity out.
Fix leaks and waterproofing promptly — the biggest driver of persistent mould.
Keep surfaces dry — squeegee shower screens and walls, wipe down condensation-prone areas.
Use dehumidifying in enclosed, damp-prone spaces like wardrobes.
Repaint with a suitable finish in moisture-prone rooms once the source is fixed.

Frequently asked questions

Why does mould keep coming back after I clean it? Because a moisture source — poor ventilation, condensation, or a leak/waterproofing failure — is still feeding it. Fix the source, not just the surface.

Is bathroom corner mould a waterproofing problem? Recurring mould at floor corners and skirting often points to a failing membrane, yes — worth an assessment.

Can mould damage my home? Persistent damp behind it can damage paint, plaster and carpentry, and it affects indoor air — so it’s worth resolving properly.

Should I just repaint over it? Only after fixing the moisture source; painting over active mould just hides it temporarily.

The bottom line

Clean surface mould safely, but if it keeps returning, chase the moisture source — ventilation, condensation, or a leak/waterproofing failure. Fix that, and the mould stays gone.

Recurring mould that points to a leak or waterproofing issue? See our waterproofing service, and if repainting is needed, our painting service. Get a free assessment today.