The condensation is on the outdoor surface
Temporary moisture on the exterior face can occur when outdoor air is humid and the glass is cooler; it is different from indoor condensation or a leak.
Why this result fits
- The room-side glass is dry.
- Moisture is clearly outdoors.
- It clears as outdoor temperature or sunlight changes.
What to do now
Confirm the side
Check from indoors without leaning out or removing a screen.
Monitor the pattern
Note the weather and whether it clears naturally.
Stop and escalate if
- Moisture appears between panes or inside the wall.
- Water enters the room.
- Glass or the frame is damaged.
What not to do
- Do not lean out of a window to wipe exterior glass.
- Do not remove fixed screens or exterior components.
- Do not seal drainage openings.
Message you can send to maintenance
Moisture appears on the outdoor surface of [window] during [conditions]. It [does/does not] clear. There is [no/some] indoor water entry or damage.
Help prevent a repeat
- Monitor from indoors.
- Report any transition to indoor leakage or damage.
If this does not match
Sources and review date
- Window Types and Technologies — U.S. Department of Energy
Content last reviewed: under the Apartmentwise methodology.