Stuck window won't open — San Francisco, California

A window that won't open usually has one of four causes: paint sealing the sash to the frame (common on older painted-shut windows), swollen wood from humidity, a broken sash cord or balance spring on double-hung windows, or hardware corrosion on casement and sliding windows. For paint-sealed windows, score the paint line between sash and frame with a utility knife, then gently tap a putty knife around the perimeter to break the seal. Swollen wood usually frees up when humidity drops — a dehumidifier helps. Broken sash cords on older double-hung windows are a classic handyman fix: the weight inside the wall is no longer counterbalancing the sash, so it falls or sticks. A handyman charges $75–$200 per window for sash cord replacement or hardware lubrication. If multiple windows are sticking after a recent paint job, the painter should return to fix it. Never force a stuck window — you can crack the glass or warp the frame, leading to much more expensive repairs.