How to clean and treat mold from AC leak?« Back to Previous Page

That black spotting is likely Stachybotrys or Cladosporium mould, which commonly grows on the constant moisture from an AC leak. Your husband's stuffy nose is a typical reaction to mould spores in the sleeping environment.

First, address the source. The AC unit must be repaired to stop the condensation leak; otherwise, the mould will return regardless of cleaning.

For cleaning small, surface-level growth, wear an N95 mask and gloves. Wipe the area with a microfiber cloth dampened with a diluted detergent solution. Do not use bleach, as it doesn't kill the roots and can worsen indoor air quality. After cleaning, the area must be dried completely with a fan.

However, mould from a leak often penetrates porous materials like drywall and ceiling insulation. Surface cleaning removes the visible stain but leaves the root structure intact. For a lasting solution, the affected drywall section may need to be cut out and replaced after the leak is fixed, especially if the staining is widespread or has been present for weeks.

Given the location directly over your bed, a professional inspection is strongly advised. An expert can assess the moisture content within the wall cavity to determine if there's hidden growth. In Dubai's climate, the high humidity can cause mould to regrow within days if not properly remediated. Companies with their own microbiology labs can take tape or air samples to identify the species, which confirms the health risk and guides the appropriate remediation protocol.