An empty property has no one running the AC, opening doors, using extract fans or spotting a leak. Over weeks it warms up, humidity climbs to outdoor levels, and mold develops in wardrobes, on cool walls and in bathrooms. Keep the AC running on a hold or humidity setpoint, leave internal and wardrobe doors open, arrange a fortnightly check, and consider a dehumidifier and a remote hygrometer. Before a short-let guest arrives, air it out and inspect.
Key takeaways
- An empty, closed property in a Dubai summer is a mold incubator.
- Keep the AC running — hold ~24 °C or a ~55% humidity setpoint.
- Arrange a fortnightly physical check that also runs the taps.
- Air out and inspect before every short-let guest.
Why empty properties grow mold
The same reasons a home grows mold after a vacation, but for longer and with no one to notice. The AC is off or on a timer that is not doing enough, water traps in unused bathrooms dry out, and a slow leak or an AC drain blockage can run for the entire vacant period. By the time anyone visits, the growth is established.
The vacancy set-up
- Leave the AC running — a hold setpoint around 24 °C, or a humidity mode targeting ~55%.
- Open every internal door and all wardrobe and cupboard doors.
- Clear and check the AC condensate drain and clean filters before the vacancy starts.
- Fix any known small leak.
- Place a dehumidifier plumbed to a drain in a known problem room, and a remote-reading hygrometer you can check from abroad.
- Pull furniture off external walls; remove anything perishable.
Periodic checks
Have someone visit every one to two weeks: confirm the AC is running and cold, run each tap and flush toilets to keep traps sealed, look and smell for any new damp, check around the AC units and under sinks, and read the hygrometer. Five minutes catches a failed AC or a new leak weeks before it becomes a remediation job.
Before short-let guests arrive
- Air the property and run all extract fans for a few hours.
- Inspect wardrobes, bathroom ceilings, under sinks and behind furniture.
- Deal with any small surface growth and its cause before the guest checks in — a musty smell is a common complaint and review.
A cheap remote-reading hygrometer pays for itself the first time it alerts you that an empty flat has hit 75% humidity while you are out of the country.