Why is water coming in through my window when it rains?
Common causes are clogged gutters, worn weatherstripping, cracked caulk at the siding joint and blocked drainage. JELD-WEN says clogged or sagging gutters can send water toward windows and their weep systems, and that weatherstrip and exterior siding joints should be inspected for cracks, voids or loss of adhesion (JELD-WEN).
What does a window leak damage?
The sill, the drywall below it, the insulation in the wall and the framing. Drywall can be dried in place if it has not swelled and the seams are intact; otherwise it is removed (EPA). Wet insulation in a wall cavity should be discarded and the cavity dried before the wall is closed up (Massachusetts DPH).
Is a leaking window covered by insurance?
Often not. Washington's insurance commissioner lists water damage from gaps between building materials, and damage that develops over more than a couple of days, as gradual leaks insurers usually don't cover (Washington OIC). A window broken by a storm is a different claim, so call your insurer.
Is rain through a window clean water?
Yes, at first. Rain through roofs, walls, windows and doors is Category 1 water (Massachusetts DPH). Water that sits in a wall for days can grow mold, so the drying still has to happen quickly.
Common questions
Can I just caulk the window?
Caulk can help if that is where water gets in, but the water already in the wall still has to dry. Find the source before sealing it.
What does fog between the window panes mean?
JELD-WEN says moisture between panes of an insulating glass unit can mean the seal has failed.
Who fixes a leaking window, a window company or a restoration company?
Often both: a window or siding contractor fixes the leak, and a restoration company dries and repairs the wall.
Related guides
Sources
- JELD-WEN: window inspection and maintenance
- EPA: Mold Remediation in Schools and Commercial Buildings, Table 1
- Massachusetts DPH: quick reference, water damage response in buildings
- Washington Office of the Insurance Commissioner: leaks, water damage and mold
Last reviewed November 13, 2026. This guide is general information, not legal, insurance or medical advice.