Condensation on windows in Dubai: inside or outside, and why it matters

Outside condensation: common in UAE summers

On hot, humid days, outdoor air touches window glass that the AC has cooled. Moisture condenses on the outside, the same way a cold drink sweats. It tells you about the outdoor air and the glass, not about your indoor humidity. Better glazing or sealing makes the difference here, not a dehumidifier.

Inside condensation: a sign to act

Water on the inside of the glass means the indoor air holds more moisture than that cold surface can handle. It often shows first in bedrooms in the morning, on windows behind curtains and around AC vents. Left alone, the frames, sills and nearby walls stay damp, which is where mold starts.

A quick test

1. Wipe one pane on the inside with a dry cloth.
2. If it stays clear, the condensation is on the outside.
3. If it fogs again within minutes, the moisture is on the inside.
4. Check a hygrometer in the room. Readings that stay above 60% confirm the indoor air is too humid.

How to reduce inside condensation

• Keep indoor humidity below 60%. A dehumidifier sized for the room is the most direct way.
• Open curtains and blinds during the day so air reaches the glass.
• Run bathroom and kitchen extract fans, and avoid drying laundry in closed bedrooms.
• Check AC drain lines and seals if water appears around vents.

Frequently asked questions