The three maintenance items that matter are clearing weep holes, cleaning tracks and sills, and replacing compressed weatherstripping. Never use abrasives, razor blades or ammonia-based cleaners on low-E glass. Twenty minutes twice a year is the whole program.
Windows are treated as maintenance-free, which is nearly true and not quite. There are three things that genuinely matter and a few things that actively cause damage.
The whole program is about twenty minutes twice a year.
The three things that matter
- Clear the weep holes. These are small drainage slots along the exterior sill that let condensation and rain drain out. Blocked with paint, dirt or insect debris, water collects in the sill channel and sits against the wood. This is the leading cause of sill rot we find and it takes seconds per window with a piece of wire.
- Clean the tracks and sills. Grit, sand, pollen and winter salt collect in sliding tracks and act as an abrasive between the roller and the track. Vacuum twice a year. This alone prevents most premature roller failure on sliding windows and patio doors.
- Check and replace weatherstripping. It compresses permanently over thousands of cycles and eventually stops springing back. It is inexpensive and it is the most commonly deferred window maintenance item.
What not to do
| Do not | Why | Do this instead |
|---|---|---|
| Use a razor blade on the glass | Scratches low-E and surface coatings permanently | Soak and use a plastic scraper |
| Use abrasive powders or pads | Scratches glass and vinyl frames | Mild soap and water |
| Use ammonia cleaners on coated glass | Can damage some coatings and seals | Glass cleaner rated for coated glass |
| Grease or oil sliding tracks | Attracts grit and makes it worse | Clean the track, then dry silicone spray |
| Pressure wash windows | Drives water past seals and weatherstrip | Hose at normal pressure |
| Paint vinyl frames | Does not adhere, voids warranty | Order the colour from the factory |
| Caulk over the weep holes | Traps water in the sill channel | Keep the weeps clear and open |
| Force a painted-shut sash | Breaks the sash or the stop | Score the paint line first, then work it free |
A twice-yearly routine
In spring, after the winter: clear every weep hole, vacuum every sliding track, rinse the bottoms of exterior doors to remove road salt residue, probe sills and jambs at the corners for soft spots, inspect the exterior caulk joint where freeze-thaw movement opens it up, and install the screens. In fall, before the winter: replace any weatherstripping that no longer springs back, adjust every exterior door threshold, swap storm panels from screen to glass, clear the weeps again, check that window wells are clear and draining, and latch every window in the house including the rooms nobody uses. That is the whole program and it is the difference between windows that last twenty-five years and windows that need attention at fifteen.
Things worth calling someone about
- Any soft spot found while probing a sill or jamb, because rot spreads and the fix is much cheaper early.
- Fog appearing between the panes, which is a failed seal and possibly still under warranty.
- A sash that will not stay up, which is a failed balance and a $75 to $250 fix.
- Water staining on interior trim or the wall below a window.
- A sliding door that is getting harder to move despite a clean track, which is worn rollers.
- Any window in a bedroom that is painted shut or will not open, because that is an egress problem.
Ranges reflect typical Capital Region projects and are for planning only. Every Sundog quote is written, itemized, and free.
Frequently asked questions
What are weep holes and why do they matter?
Small drainage slots along the bottom exterior sill of a window that let condensation and any water past the sash drain back outside. When they block with paint, dirt or insect debris, water collects in the sill channel and sits against the wood, which is the leading cause of sill rot. Clearing them takes seconds per window.
How should I clean low-E windows?
Mild soap and water with a soft cloth or a squeegee. Avoid abrasive powders, scouring pads, razor blades and ammonia-based cleaners, which can damage coatings. If something is stuck on, soak it and use a plastic scraper rather than a blade.
Should I lubricate my window tracks?
Clean them rather than lubricate them. If you want a lubricant after cleaning, use a dry silicone spray. Never use oil, grease or white lithium, which attract grit and turn the track into an abrasive paste that destroys rollers faster than no lubricant at all.
How often should window weatherstripping be replaced?
Every five to ten years on windows in regular use, sooner on a door. It compresses permanently and eventually stops springing back, at which point it seals nothing. It is inexpensive and it is the most commonly deferred maintenance item on a window.
Can I pressure wash my windows?
Not recommended. Pressure washing drives water past weatherstripping and seals that are designed for rain rather than directed high pressure water, and it can force water into the wall assembly around the opening. A garden hose at normal pressure is fine.
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