Mould on walls: how to remove and prevent it

Mould grows where there's damp and little air. Cleaning it is easy, but if you don't remove the cause it comes back: here's how to do both.

Why it forms

Three ingredients: damp (condensation, leaks), poor ventilation and cold surfaces. Typical in north-facing corners and behind furniture against the wall.

How to clean it

Wear gloves and a mask. Use a solution of water and baking soda or an anti-mould product; leave it, scrub and dry well. White vinegar also works for delicate surfaces.

Remove the cause

• Air the room every day, especially after showering and cooking.
• Move furniture a few centimetres off cold walls.
• Wipe condensation off windows and tiles.
• If there's a real leak, go to the root: anti-mould paint alone isn't enough.

When it's a serious problem

If the mould always comes back in the same spot or spreads, there may be a leak or a thermal bridge: then you need work on the structure, not just cleaning.