How to Remove Mould from Walls and Ceilings

Removing mould from walls and ceilings is not merely a cosmetic concern: dark patches point to damp, poor ventilation or water ingress, and can worsen allergies and respiratory problems. Professional decorators therefore tend to work on two fronts, eliminating visible fungal growth while taking steps to prevent it from returning too quickly, using straightforward products, ventilation improvements and, where needed, suitable repainting.

How can you identify the cause of mould on walls?

Before cleaning begins, professionals assess where the moisture is coming from, as this determines whether sanitising the area will be enough or whether structural repairs are required. Signs such as blistered plaster, paint peeling away in sheets, or patches that spread rapidly suggest water ingress and require a plumber or waterproofing specialist.

Where damp is only on the surface, usually due to limited airflow or steam from showers and cooking, the issue can generally be dealt with through careful cleaning and minor repairs. Even so, monitoring the wall for several days helps confirm whether the problem has genuinely been brought under control.

Watch a video on the Clube do Pintor YouTube channel about effective homemade mixtures for cleaning damp marks and preventing mould from returning:

https://www.youtube.com/watch?v=qMiwKIn0N7w

How to clean mould from walls step by step

The most widely used method for removing mould from a wall combines water and bleach in equal parts. Apply it directly to the marks using a sponge, cloth or spray bottle, always keeping the windows open. Some decorators add a small amount of neutral detergent to lift grease and built-up dirt, allowing the mixture to work for a few minutes before gently scrubbing the surface.

Another common option, particularly for small bedrooms or for people sensitive to the smell of chlorine, is undiluted white spirit vinegar. Apply it to the mould and leave it for 20 to 30 minutes before wiping with a dry cloth. In larger areas or where mould is more advanced, specialist anti-mould products can supplement the initial cleaning.

How to prepare a mouldy wall for repainting

Once the visible mould has been removed, the area must dry fully for several hours or up to a full day; do not paint while the wall remains damp. When the surface is dry, many decorators lightly sand it with fine sandpaper to even it out and remove loose residue, filling small holes with filler before sanding gently again.

An acrylic sealer or stabilising primer is then recommended, as it improves paint adhesion and helps block light damp. For the finish, washable acrylic paints or products labelled anti-mould are preferred. In kitchens, bathrooms and utility rooms, paints formulated for damp environments provide greater resistance to steam and condensation.

What helps prevent mould from returning?

Getting rid of mould is only one part of the solution: daily habits reduce trapped moisture and maintain airflow, making it harder for marks to reappear. In cold or rainy locations, a quick visual inspection whenever the season changes can reveal early mould spots, which are far easier to deal with.

Some straightforward measures recommended by decorators and home maintenance specialists can be followed regularly:

• Keep doors and windows open for a few minutes each day to refresh the air.
• Avoid drying clothes in bedrooms or living rooms, using outdoor washing lines or well-ventilated areas instead.
• Use extractor fans, fans or dehumidifiers in naturally damp rooms.
• Check gutters, roofs and pipework periodically for signs of water ingress.
• Position large furniture a few centimetres away from walls to reduce condensation.

When small patches appear, cleaning them promptly with the recommended methods and improving ventilation will usually prevent major refurbishment work. This keeps the space visibly cleaner, reduces unpleasant odours and lowers the risk associated with fungal growth inside the property.