Black mold on wall: DIY vinegar or call professional?« Back to Previous Page

That black speckling is a classic sign of a surface mould bloom, and it's very common here after a humidity spike. The high humidity we've had, combined with the temperature difference between your villa's walls and the cooled indoor air, creates perfect conditions for condensation and mould growth.

For a small, surface-level patch (less than one square meter), a DIY approach can be effective. Use a solution of 70% vinegar and 30% water, which is often more effective than bleach for many common mould types here. Spray, let it sit for an hour, then scrub with a stiff brush and wipe clean. Wear an N95 mask and gloves during the process. However, this only addresses the visible growth.

The critical question is what's happening inside the wall. If the discolouration appeared suddenly and is near an external wall or an AC unit, there could be a hidden moisture source like a minor leak or significant condensation within the partition. DIY cleaning will fail if the moisture issue isn't resolved.

If the area is larger than a square meter, if the mould returns quickly after cleaning, or if there's any musty odour, a professional inspection is recommended. They can use moisture meters and borescopes to check inside the wall cavity for hidden growth and identify the exact moisture source. In many villas, this is due to thermal bridging or inadequate vapour barriers, which are common in our climate. Proper remediation in such cases involves isolating the area, removing affected materials if necessary, and applying antimicrobial coatings to prevent recurrence, followed by verification testing to ensure the space is truly clean.