Black mold in bathroom: call cleaner or maintenance first?« Back to Previous Page

The grout between the tiles in my master bathroom shower has started turning black and feels a bit soft in the corners, and I just noticed it's spreading to the wall behind the toilet. We've lived here in Jumeirah for 2 years and just noticed this last week. I'm worried it's mold and that it's a bigger issue behind the walls. What's the best way to handle this—should I call a specialized cleaning service first, or get a maintenance company to check for water damage right away?
Posted by Khalid Farah
Asked on May 26, 2026 12:00 pm
0
Black grout that's soft to the touch and spreading to other walls is a strong indicator of a moisture problem, not just surface mold. In Dubai's high humidity, this often points to a leaking pipe or a failed waterproofing membrane behind the tiles.

Call a maintenance or water damage specialist first, not just a cleaner. A specialized inspection will use moisture meters to check the walls for saturation. Surface cleaning is temporary; if there's a leak or compromised waterproofing, the mold will return quickly and the structural damage will worsen. The Dubai Municipality's building codes have specific requirements for bathroom waterproofing for this exact reason.

While you wait for inspection, increase ventilation. Run the bathroom exhaust fan for at least 30 minutes after every shower and ensure the AC is functioning properly to manage ambient humidity, which accelerates this issue. Do not attempt to scrub it aggressively, as this can aerosolize spores.

If the inspection confirms the damage is only superficial, a professional cleaning service using EPA-approved disinfectants can then address it. However, if the moisture reading is high, the tiles and grout will likely need to be removed to repair the leak and the membrane—a job for a maintenance contractor. A reputable provider should be able to explain the process and may recommend post-remediation verification to confirm the environment is back to a healthy standard.
Posted by Sani Admin
Answered on May 28, 2026 6:32 pm