Should I urgently fix black mold under shower sealant?« Back to Previous Page

The black spots under silicone sealant are almost certainly mold, and yes, this requires prompt attention. In Dubai's high humidity, this mold is actively growing, and the musty smell confirms it has likely spread behind surfaces.

You should address this within the next few weeks. Leaving it allows the colony to expand deeper into the wall, potentially compromising drywall or backing boards, which becomes a significantly larger repair. The rising seasonal humidity will only accelerate this.

For a small, visible patch, you can clean it yourself with a dedicated mold-removing cleaner, but the critical step is fixing the moisture source. Simply replacing the sealant over a damp wall will cause it to return quickly. The area must be completely dry first.

However, the persistent musty odor throughout the bathroom suggests a wider issue than just the visible spots. This often indicates mold growth within the wall cavity, possibly from a slow leak in the plumbing or shower pan. In such cases, a professional inspection is necessary to identify the full extent and the source of the moisture. They can use moisture meters and borescopes to assess the damage behind the tiles without unnecessary demolition.

After remediation, improve ventilation by running the bathroom exhaust fan for at least 30 minutes after every shower and consider a dehumidifier. When resealing, use a high-quality mold-resistant silicone.