Planning a trip? Use the pre-travel checklist. Manage a property empty for months? See mold in an empty property. This page is for when you have already come home to it.
Mold appears after a vacation because the home was warm, closed and unventilated while outdoor humidity stayed high. With the AC off, indoor surfaces warmed up, humidity climbed, and it condensed inside wardrobes and on cool external walls for weeks. The fix is to leave the AC running at a moderate setpoint or on a humidity setting, keep internal doors and wardrobes open, and have someone check in.
Key takeaways
- An empty home in a Dubai summer is warm, sealed and humid — ideal for mold.
- Turning the AC fully off for weeks is the single biggest cause.
- Closed wardrobes and rooms trap the most moisture, so leave them open.
- Set the AC to hold ~24 °C or use a humidity setpoint, and ask someone to visit.
Why a closed home grows mold while you are away
Three things change when you lock up and leave. The air conditioning stops removing moisture, so indoor humidity drifts up towards the outdoor level, which in a Dubai summer sits well above 60%. Indoor surfaces slowly warm to near outdoor temperature, and the coolest spots — external walls, slab edges, the backs of wardrobes — become condensation points. And with no one opening doors or running extract fans, that damp air just sits. Over two or three weeks, that is more than enough time for growth to establish on paper, fabric, leather and painted gypsum.
Where it shows up first
- Inside wardrobes and closed cupboards — still air against a cool external wall, plus leather shoes and cotton that hold moisture.
- On the ceiling and walls near AC diffusers — these surfaces were cold for months and any residual duct moisture had nowhere to go.
- Bathrooms — water in traps evaporates, humidity builds, and there is no extraction.
- Behind and under furniture on perimeter walls.
Before you travel: a short checklist
- Do not switch the AC off completely for a long summer absence. Set it to hold a moderate temperature (around 24 °C) or, if the unit supports it, a humidity setpoint near 55%.
- Leave internal doors open and wardrobe and cupboard doors ajar so air can circulate.
- Clear any blocked AC condensate drain and have a service done if one is overdue.
- Move furniture a few centimetres off external walls.
- Ask a neighbour, family member or building service to check the property every week or two, run the taps briefly, and confirm the AC is still working.
- Consider a plug-in hygrometer you can check remotely, or a small dehumidifier in a known problem room.
What to do when you get back
Open up, run the AC and all extract fans, and let the place dry for a day before judging the extent. Wipe small surface marks on hard, cleanable surfaces and dry them fully. Air out or launder affected clothing; leather and heavily affected soft items may not be salvageable. If growth is widespread, inside the AC, on porous gypsum, or keeps returning after you have cleaned it, get a professional assessment rather than repeating the cleaning.
Get help if the growth covers a large area, involves the AC system or ceiling voids, or the same spots return within a few weeks of cleaning.