AC mold: DIY with bleach or call a pro?« Back to Previous Page

That black growth is likely Stachybotrys chartarum, a toxigenic mold that thrives in the constant moisture from your AC leak. Given Dubai's high humidity and year-round AC use, these conditions are perfect for rapid mold proliferation.

Using bleach is not recommended. It is mostly water, which can feed the mold roots deep in porous materials like drywall. Bleach also fails to address the root cause: the moisture problem. The leak must be repaired first, or the mold will return quickly.

For a small patch (under one square foot), you might manage it yourself with a dedicated EPA-approved fungicide, proper PPE (N95 mask, gloves, goggles), and sealing the area. However, since it's behind the unit, spreading, and affecting your health, this indicates a more established colony. Spores are likely circulating through your AC system, explaining your worsened allergies.

In this case, a professional assessment is strongly advised. Remediation for a single room typically involves isolating the area with containment barriers, using HEPA filtration to capture airborne spores, and removing contaminated porous materials like the affected drywall. The final, critical step is a post-remediation verification test from an independent lab to confirm the air quality is safe. The cost for a professional job is driven by the extent of contamination and the required containment procedures, so it's best to request an on-site assessment for an accurate scope and quotation.