Window Inspection Checklist

Check the panes of glass for cracks or breaks and ensure they’re sealed correctly:

• If you find cracks on glass in wood single-pane windows, you can get replacement glass cut to fit at your local Lowe’s. Carefully remove the broken glass — typically from the exterior — and use reglazing compound to replace the broken pane.
• Check the glazing around the exterior of wood-frame windows and reglaze panes as necessary.
• If you have multipaned windows, check for moisture between the panes or any other evidence of leakage. Let a professional handle repairs to ensure the window maintains energy efficiency.
• Clean small areas of mold on the glass with mold remover or a mild detergent and water. Wear eye protection, cleaning gloves and a respirator.

The window sash is the structure that holds the glass. Check your sashes for leaks, damage and operation:

• Check to make sure the sashes aren’t warped or cracked.
• Ensure they hold the panes securely and fit in the frame squarely.
• With the sash closed, use a piece of tissue or thread to check for drafts.
• If the sashes open and close, make sure they operate smoothly.
• Apply silicone lubricant to the tracks and moving parts as necessary.
• Check the weatherstripping and replace it if you find damage or wear.
• Ensure the locks work. Install replacement locks as necessary.
• If the windows tilt in for cleaning, test the movement and latches. Replace the latches as necessary.
• Clean the sash and apply touchup paint or stain and sealer where necessary.
• Clean away any mold and mildew.
• If you have a wood sash, check for water damage and rot. You can repair small areas of rot by removing the rotten wood and filling in with epoxy wood filler.

Damaged or rotting sashes and those that are difficult to open might require professional repair or might indicate it’s time for replacement windows. Take a look at our replacement window guide and see how to replace windows. Don’t have time to do it yourself? Let us install your windows.

Inspect your window screens and storm windows if you have them installed:

• Check for holes or tears in the screen. Patch any damage. Screen replacement is a simple DIY project. You can find replacement window screens that focus on views, durability, privacy and more.
• Check the spline that secures the screen fabric to the frame to ensure it’s intact and in place.
• If the screens open and close, ensure they operate smoothly.
• Remove the screens, if possible, and clean them.
• If you have storm windows, inspect the glass for cracks and ensure the seals around the frame are in place. Clean mold and mildew and look for evidence of leaks.
• Clean the storm windows.
• Apply silicone lubricant to the screen and storm window tracks as necessary.

The window frame supports the sashes and, in single- and double-hung windows, supports the tracks that allow the sashes to open and close:

• Make sure the frames are sealed to the house. Replace the caulk inside and outside if necessary.
• Ensure the frame is in good condition and square, allowing easy movement of the sashes.
• As with the sashes, check for cracks, water damage, warping and, with wood frames, rot. Patch small areas of rot with epoxy wood filler.
• Check for mold and mildew. Clean small areas with mold remover or a mild detergent and water solution.
• Wipe or vacuum dirt and debris from the sill.
• Ensure the weep holes at the bottom of your exterior window frame are clear and can drain water away efficiently.
• Touch up paint or stain and sealer as needed.

As with the window sash, a damaged window frame might need professional repair or replacement, but you can make some repairs on a damaged wood windowsill.

The window casing is the moulding that gives your windows a finished look inside the home:

• Check the casing and stool — the shelf on the interior, and the surrounding wall for any signs of water damage, such as stains or bubbled paint. Touch up the paint or replace small areas of damage as necessary.
• Locate and seal leaks.
• Clean away any mold or mildew.
• Check for cracks or gaps in the casing pieces. You can fill small gaps with spackling or paintable caulk. Sand and paint the repair.