How to Close a Stuck Basement Window

Open the window slightly more, if possible. When a basement window won’t close, it still usually opens farther. Opening it more can jar loose anything that’s preventing it from closing.

Look on each side of the window for debris or loose nails and screws. Basement windows with old framing often have nails or screws that eventually loosen from wear and tear and stick out just enough to prevent the window from closing. Remove any debris and replace loose screws and nails.

Sand off a portion of the frame that’s preventing the window from closing. Old frames, especially if installed incorrectly, can become warped or start to sag. You can remedy the problem by sanding the problem area. Sand only a small bit at a time, then check to see if the window closes. Do not sand the frame if it’s encased in vinyl.

Look for evidence of paint along the window sash and frame. If you see any, insert a thin knife — such as a putty knife — into the paint to crack it. Windows that are left open for long periods sometimes become sealed open from paint.

Run a dehumidifier in your basement. If your basement is considerably humid, your window’s frame can swell, causing the window to become stuck open. Removing the humidity from the room allows the frame to shrink and enables you to close the window.