How To Straighten a Window in 8 Steps

If your windows are difficult to open or close, or if they’re producing drafts, they’re probably misaligned, and it’s time to straighten them. Misaligned windows can compromise your home’s energy efficiency and lead to potential operational problems. You can frequently fix this problem with some do-it-yourself grit, though. Learn how to spot a misaligned window, how to straighten it, and how to maintain your work in the guide below. 

Signs of a Misaligned Window

Window misalignment can occur when a house starts settling, or because of improper installation. A crooked window may display the following signs:

• Difficulty opening or closing the window: A window may bind or stick if the sash or frame is out of alignment.
• Inconsistent measurements across the window opening: Uneven measurements are typically the products of misalignment, and can affect the window’s seal. 
• Uneven gaps between the sash and frame: Misalignment can create uneven gaps, which can make the window less efficient and compromise its ability to insulate.
• Unusual noise during operation: If your window scrapes or grinds when you open or close it, it’s probably misaligned. 
• Visible light or air leaks around the edges: Misalignment can produce gaps that lead to light or air leaks. This can make your home less energy efficient and increase heating or cooling costs.

Tools and Materials Needed to Straighten a Window

Collect the following tools and materials before you start straightening your windows:

• Flat pry bar
• Hammer
• Level
• Measuring tape
• Nail gun
• Shims
• Spray foam insulation that’s designed for windows and doors
• Utility knife
• Wood glue

Steps To Fix a Crooked Window

Follow our step-by-step guide below to straighten your windows: 

Step 1: Prepare the Window for Straightening

Prepare the work area and remove any obstructions before you begin adjusting the window:

1. Clear the area around the window so you can easily access it.
2. Clean the window frame and sill to remove dirt and debris.
3. Inspect the window for any visible damage or rot.
4. Remove curtains, blinds, or other window treatments.

Step 2: Remove the Window Casing

1. Carefully pry the casing away from the wall using a flat pry bar.
2. Use a utility knife to score along the edges of the casing where it meets the wall and window jamb.
3. Set the removed casing aside in a safe place.
4. Work slowly to avoid damaging the casing. You’ll reuse it later.

Step 3: Assess the Window Frame

1. Check for gaps between the window frame and the rough opening.
2. Look for any signs of damage or rot in the frame or surrounding structure.
3. Measure the width of the window opening at the top, middle, and bottom.
4. Compare these measurements to determine where, exactly, the frame is out of square.

Step 4: Shim the Window Frame

1. Cut away a small portion of the wallboard with a utility knife to expose the rough opening.
2. Insert shims between the window frame and the rough opening.
3. Start with the sides of the window, and work from the bottom up.
4. Add shims to the top and bottom of the frame.
5. Occasionally test the window to make sure you’re not over-tightening.

Step 5: Secure the Window Frame

1. Avoid using too many nails, which can warp the frame.
2. Open and close the window to make sure it hasn’t shifted. 
3. Place nails through the shims for added stability.
4. Use a nail gun to fasten the window frame and shims to the rough opening.

Step 6: Insulate Around the Window

1. Apply low-expansion spray foam insulation that’s designed for windows and doors.
2. Allow the foam to cure according to the manufacturer’s instructions.
3. Fill gaps between the window frame and rough opening, and be careful not to overfill.
4. Trim excess shim material with a utility knife.

Step 7: Reattach the Window Casing

1. Apply wood glue to the back of the casing.
2. Carefully put the casing back into place.
3. Clean any old adhesive or debris from the casing and surrounding area.
4. Fill nail holes with wood filler and touch up paint.
5. Use a nail gun to secure the casing every 12–16 inches.

Step 8: Check Window Operation

1. Look for any remaining gaps or air leaks around the frame.
2. Lock and unlock the window to make sure it’s properly aligned.
3. Open and close the window several times to make sure it moves smoothly.
4. Make sure the window stays in place when it’s partially open.

Window Maintenance Tips

Performing routine maintenance will keep your window in excellent condition and prevent future misalignments. Consider the tips below.

• Check seals and insulation: Inspect seals and insulation around the windows. Replace any worn weatherstripping and reapply caulk as needed. Make sure the new materials fit correctly.
• Clean your windows: Use a non-abrasive cleaner and soft cloth to clean the windows and frames.
• Inspect for damage: Inspect the window frames and sashes for any signs of damage, and address any issues immediately.
• Keep tools handy: Keep a toolkit handy that includes essential items for window maintenance, such as a putty knife for scraping old caulk and a small brush for cleaning tracks. 
• Lubricate moving parts: Apply lubricant to moving parts such as hinges, locks, and tracks to keep things running smoothly. Use products that are specifically designed for window hardware.

Tools: