Seasonal Window Maintenance Calendar
A simple four-season checklist for northern Illinois homes.
Most window repairs start as small problems that were easy to prevent. A few minutes each season keeps them small.
This calendar is built for northern Illinois — long, snowy winters, wet springs and humid summers. Follow it and your windows will need far fewer repairs.
Spring
March – May- Check every sill and sash bottom for soft wood after the winter.
- Look for cracked paint and caulk; note spots to repaint.
- Clean tracks and weep holes so spring rain drains.
- Swap storm panels for screens and check screens for tears.
Summer
June – August- Repaint wood sills and sashes where paint has cracked.
- Re-caulk exterior joints in dry weather.
- Lubricate cranks, hinges and tracks with dry silicone.
- Book repairs now — it's the best weather for wood and glazing work.
Fall
September – November- Clean gutters so they don't overflow onto windows.
- Check weatherstripping for flattened or missing sections.
- Swap screens for storm panels and clear storm weep holes.
- Test every lock — windows should close and lock tight before winter.
Winter
December – February- Keep snow cleared off sills and away from basement windows.
- Don't force stiff cranks or frozen sashes — let them warm up.
- Watch for fog between panes on cold mornings — a sign of seal failure.
- Keep indoor humidity moderate to limit condensation on the glass.
Why These Tasks Matter
Spring inspection catches winter damage while it's small. Snow and meltwater sit on sills for weeks, and a soft spot found in April is a small repair; found two winters later, it can be a full sill rebuild.
Paint is the wood's protection. Bare or cracked paint lets water into the wood, and sills and sash bottoms are where it starts. Repainting before paint fails is the cheapest window maintenance there is.
Clean tracks and weep holes keep water moving. Blocked weep holes trap water against sills, and gritty tracks strain rollers, balances and cranks until they fail.
Fall weatherstripping and lock checks stop drafts. A locked window pulls the sash tight against its seals; a window that won't lock is almost always a drafty one.
Winter humidity control protects interior sills. Heavy condensation runs down the glass and soaks into the interior sill. Keeping indoor humidity moderate prevents that — see why windows fog up in winter.
What Skipping Maintenance Costs
- Repainting a sill costs a little paint; rebuilding a rotted sill typically costs $200–$700.
- Clearing storm-window weep holes takes minutes; rot they cause on the main sill can mean the same sill repair.
- A yearly squirt of dry silicone on a casement crank is nearly free; a stripped crank operator typically costs $150–$450 to replace.
- Replacing worn weatherstripping ($100–$300) is far cheaper than living with drafts every winter.
Full price list: window repair cost guide → · Getting older windows ready for the cold: how to winterize old wood windows →
Related repairs: Window sill repair · Leaking window repair · Storm window repair
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