Stop drafts, whistling and leaks without replacing the window.
Licensed & bonded · WA contractor reg. PUGETPL744JM
Note the word: gasket, not weatherstripping. European windows seal with rubber or elastomer profiles set in grooves on the frame and sash, two or three lines of them. When the handle turns down, the locking cams pull the sash onto those gaskets. If the cams are loose, the gasket is crushed flat, shrunk at a corner or pulled out of its groove, air and water find the gap. Most of the time, it's fixable in a visit.
Signs of a seal problem
- Cold draft you can feel with the back of your hand along one edge.
- Whistling or humming in a strong wind.
- Water on the inside sill after wind-driven rain.
- A gasket that's flattened, cracked, sticky, shrunk away from the corners or hanging out of its groove.
- Light visible between sash and frame when closed.
- More condensation along one edge.
What causes it
| Cause | What it looks like |
|---|---|
| Low cam compression | Gasket looks fine, but draft or whistle at one edge |
| Sash out of alignment | Uneven gaps; seal touches on one side only |
| Compression set (age) | Gasket permanently flattened, no spring left |
| Shrinkage | Gaps at corners where gasket was stretched in |
| Paint or sealant on the gasket | Hard, cracked, sticking to the sash |
| Blocked drainage | Water at the sill even though seals are fine |
| Installation leak | Water inside the wall or trim, not at the sash; a different repair |
Water at the sill isn't always the seal. Often it's a blocked drain slot.
How we fix it
- Find the leak path: check for air and water leaks at the sash and around the frame.
- Clear and test drainage.
- Re-align the sash and set cam compression.
- Re-seat gaskets that have slipped.
- Replace worn gaskets with the matching profile. Gasket profiles are system-specific, so we match them by sample or system. Some are stocked; others are ordered, usually arriving in under a month.
- Treat gaskets with a gasket care product.
- If the leak is from installation (around the frame, not at the sash), we'll explain what we found and what it takes to fix it.
What you can do
- Clean gaskets with mild soapy water; dry them.
- Each spring and fall, wipe on a gasket care product made for rubber window seals (avoid petroleum-based products); it keeps the rubber supple.
- Never paint gaskets or seal over them.
- Press a gasket that's slipped back into its groove with your thumb.
- Clear drainage slots outside.
- Tissue test: close the window on a sheet of paper. If it slides out easily at one spot, compression is low there.
Yes, we service gaskets on European tilt-and-turn and casement windows and European sliding/patio doors from any supplier.
We don't publish prices. Pricing depends on your distance from Seattle and the number of windows, so call (425) 678-5158 or send a service request with photos for a quote. We'll always tell you the cost before we start work.
Call (425) 678-5158 · Request service →