What's actually causing this
Wood windows absorb humidity and swell during summer. Painted windows get sealed over time as coats of paint build up in the gap between the sash and the frame. Older double-hung windows also lose their balance springs.
What you'll need
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- Utility knife Shop →
- Putty knife or window zipper Shop →
- Sandpaper (80 grit) Shop →
- Candle wax or silicone spray Shop →
Step-by-step fix
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1
Score the painted seam
Run a utility knife along the gap between the sash and the frame — inside and outside. This cuts the paint seal without damaging the wood.
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2
Break the seal with a putty knife
Insert a wide putty knife into the seam and tap it gently with a hammer to work around the perimeter. Work slowly to avoid cracking the glass.
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3
Sand swollen edges
Open the window enough to access the edges. Sand any swollen areas with 80-grit sandpaper until the sash slides freely.
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4
Lubricate the channels
Rub candle wax or apply silicone spray to the window channels and the sash edges. Do not use oil-based lubricants — they attract dirt and degrade wood.
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5
Test and repaint if needed
Open and close the window several times. If you sanded bare wood, apply primer and paint to prevent future swelling.
Door and window contractors in Washington typically charge $100–175/hr. Window replacement averages $300–800 per window, while entry doors run $800–2,500 installed.
Permits and inspections requirements vary by Washington. Check with your local building department before starting.
Brick and stone masonry dominant. Pointing and repointing frequent. Wood frame and clapboard common on rowhouses. Slate and tile roofing on historic homes. Wood rot is concern in freeze-thaw climate.
Standard door and window maintenance applies in Washington's climate.
DIY in Washington: DC's strict codes, historic preservation requirements, and high licensing standards restrict DIY repairs. Most homeowners must hire licensed professionals. Permits are expensive. Non-compliance costs are high.
- The window frame is visibly bowed or twisted.
- The sill is rotted — the entire window unit may need replacement.
- A double-hung window sash falls when released (broken balance spring or spiral rod).
- The window is part of a casement and the crank mechanism is broken.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Washington.
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