Mould comes back after painting because paint treats the stain, not the moisture that feeds it. If a leak, a damp wall, a blocked AC condensate line or poor ventilation is still there, the wall stays wet under the new coat and the mould returns. The fix is to find the moisture source first, correct it, and only then repair the surface. A repaint on its own can even hide the problem for a while.
What reports from the UAE show
Residents in several emirates have described the same cycle.
- Abu Dhabi, 2015. The National (8 March 2015) reported a tenant who called maintenance eight or more times. The walls were scraped and repainted, and the paint peeled again within two or three days.
- Sharjah, 2018. Gulf News (September 2018) reported a family forced out of a Sharjah home by fungus. The family's doctor blamed a rushed repaint that trapped moisture.
These are news reports, not tests, and they are several years old. What they share is the sequence: visible mould, a cosmetic fix, and then regrowth.
Why paint fails
- Paint is not a moisture barrier. Damp behind a wall pushes outward. Paint blisters, peels or stains, and mould grows on the film and in the plaster underneath.
- The surface is the symptom. Mould shows where moisture settles. Wiping or covering it leaves the cause in place.
- A wet wall painted too soon. If the wall has not dried, the coat can trap the moisture, which is what the Sharjah family's doctor described.
- Humid rooms stay humid. A bathroom with no working extract, or a bedroom with a cold external wall, will keep supplying moisture.
The usual moisture sources in UAE homes
MUMTAZ lists these as the sources it looks for:
- A blocked AC condensate line
- Failed silicone around a bath, shower or basin
- Cold bridging, where a cold wall or slab meets warm humid air
- A room with no working extract
A leak from a neighbour, a pipe or the roof is also possible, and that may be the landlord's or the building's to fix. If the cause sits with the building, say so in writing with a photo record.
Signs the cause is still there
- Paint blisters, flakes or peels again at the same spot.
- A musty smell returns after a few days or weeks.
- Staining or darker patches show through the new coat.
- The wall feels cool or damp, especially near an AC unit, a bathroom or an external wall.
If you rent, report it in writing before you repaint, and read who pays for mould in a UAE rental in our tenant and landlord guide. Tenants in Sharjah and Dubai describe the same cycle.
What fixes it
- Stop the moisture. Clear the condensate line, replace failed silicone, repair the leak, restore the extract.
- Let the surface dry. Do not repaint a damp wall.
- Treat the mould. Remove the growth from the affected surfaces.
- Repair and repaint last. Once the cause is fixed and the surface is dry, painting makes sense.
If you have already repainted and the mould has returned, do not repaint again. Have the cause found. If anyone in the home has a cough or breathing worry, see a doctor.
What MUMTAZ does
Mould inspection, AED 299 incl. VAT. It includes:
- An inspection of the affected rooms by a MUMTAZ surveyor
- Finding the moisture source, such as a blocked AC condensate line, failed silicone, cold bridging or a room with no working extract
- A photo report of what we found and what needs to change, including any fix that belongs to the landlord or the building
- A written remediation quote, so you know the price before any work starts
It does not include laboratory sampling or species identification. If you go ahead with treatment, home mould treatment is priced per affected room: AED 840 for one room, AED 1,155 for two and AED 315 for each room after that, VAT included.
If the moisture source turns out to be the building, the photo report says so and you can pass it to your landlord or agent. See our mould and fungus remediation page, and for AC-related mould our AC mould and coil disinfection service. We work in Sharjah and Dubai.