After hundreds of jobs around our area, this is one of the calls we get most once the fall rains settle in. A homeowner in our area notices a damp sill, a drip at the top of the frame, or paint starting to bubble after a storm — and wants to know where the water is actually coming from. Good news: window leaks usually start small. Here is what we look for first.
Failed exterior caulk (the most common cause)
The sealant around the outside of your window frame takes a beating from sun, rain, and temperature swings. After a few years it cracks, shrinks, and pulls away from the siding or trim — and wind-driven rain finds those gaps fast. Walk around your house on a dry day and look closely at every window: if you can see a crack or a gap in the bead around the frame, water can get in. This is exactly what our caulking and weatherstripping service handles — we cut out the failed sealant and reseal it properly, not just smear new caulk over old.
Blocked weep holes
Most modern windows have small drainage slots — weep holes — along the bottom of the frame. They let water that gets into the track drain back outside. When they clog with dirt, fir needles, and spider webs, that water has nowhere to go except in. A soft brush and a quick check each fall keeps them clear.
Water coming from above the window
If the drip appears at the top of the frame, the window itself may not be the problem at all. Overflowing gutters can dump a sheet of water down the wall and behind the trim, and damaged or missing flashing above the window lets rain run straight in. If your gutters spill over during storms, start there — our gutter cleaning service clears the run and the downspouts so water goes where it should.
Rotted trim and peeling paint
Paint is a water barrier, not just a color. Once paint peels and bare wood sits through a wet PNW winter, trim boards soften and rot, and every storm pushes a little more water inside. Probe the trim around your windows with a screwdriver — if it feels soft or crumbly, that section needs repair before resealing will hold. Left alone, the moisture reaches the wall and shows up as stained, soft drywall inside; that is a drywall repair on top of the exterior fix.
Leak or condensation? A quick test
Not every wet window is a leak. On cold mornings, warm indoor air condenses on cold glass and runs down to the sill. The tell: condensation shows up on calm, cold mornings and wipes off the glass itself, while a true leak shows up during or right after wind-driven rain, usually at one corner or along the top. Knowing which one you have saves you from sealing a window that was never leaking.
How to stay ahead of it
- Inspect the caulk around every window each fall and reseal any cracked or separated beads.
- Clear the weep holes and window tracks so water drains out, not in.
- Keep paint on exterior trim in good shape — touch up peeling spots before winter.
- Keep gutters clean so storm water is not pouring down the wall over your windows.
- After the first big storm of the season, check sills and walls inside for damp spots while the evidence is fresh.
FAQs
Can I reseal my own windows?
Yes, small gaps are a fair weekend job: remove the old failed caulk first, let the joint dry fully, and use a quality exterior sealant. If the trim is rotted or the leak is at the top of the frame, have it looked at — sealing over a bigger problem traps water inside the wall.
Why does my window only leak during heavy rain?
Wind pushes rain sideways into gaps that stay dry in a light drizzle, and heavy rain overwhelms clogged weep holes and gutters. A leak that only appears in big storms is still a leak — it just needs the right conditions.
Can a window leak damage my house?
Yes. Slow leaks rot trim and framing, stain and soften drywall, and feed mold inside the wall. Caught early, most are a simple reseal; ignored for a season or two, they become a repair project.
Book Your Visit
Seeing water where it should not be? We can help you with that at Pro Touch — book your appointment or call/text (253) 298-9025. Licensed · Bonded · Insured — WA Reg. #PROTOTH762KL.