Through the Dubai summer, keep indoor humidity below 60% by running the AC at a moderate setpoint for longer periods, servicing it before the season starts, and keeping extract fans working and used. Watch the enclosed spots — wardrobes, store rooms, bathrooms, cool perimeter walls — because that is where it starts. Deal with any small growth immediately rather than waiting for autumn.
Key takeaways
- Service the AC (coil, drain, filters) before summer, not during.
- Run the AC longer at a moderate setpoint — do not chase very cold in short bursts.
- Keep humidity under 60%; monitor wardrobes and store rooms.
- Act on small growth straight away in summer — it spreads fast.
Why summer is the risk period
From late spring the outdoor air is hot and often 50–90% relative humidity. Every door opening, every fresh-air intake and every gap in the envelope brings that moisture in. The AC is working hard just to keep temperature, and if it is not sized, maintained or run to also dehumidify, indoor humidity creeps up. Warm, humid, and something to grow on — the season does the rest.
Getting the AC right for summer
- Service before the season — coil clean, condensate drain and pan checked and cleared, filters cleaned or replaced. A mid-summer filter check too.
- Run it to dehumidify — a moderate setpoint (around 23–24 °C) held for longer periods removes more moisture than very cold, short cycles. Use a dry mode if the unit has one.
- Keep it running even in unoccupied rooms — a closed, warm room is where growth starts.
Everyday habits that matter more in summer
- Run kitchen and bathroom extract fans during and after use, every time.
- Keep balcony and external doors closed.
- Do not dry laundry indoors without ventilation.
- Leave wardrobe and cupboard doors ajar periodically; keep internal doors open.
- Keep furniture a few centimetres off external walls.
What to watch
Check the usual first-appearance spots once a week through summer: inside wardrobes on external walls, store rooms, bathroom ceilings, window reveals, and behind furniture on perimeter walls. A hygrometer in a problem room takes the guesswork out. If you find growth, clean it and address the cause the same week — in summer conditions a small patch becomes a large one quickly.
Book the AC service in March or April. In June every AC company in Dubai is booked out, and a unit that fails mid-summer can grow you a mold problem in a week.