How to Order and Install Glass Block Basement Windows

Glass blocks create an attractive, secure accent window.

When you don't need or want basement windows to open, either for home security or aesthetics, install glass-block windows for stylish look that restricts a clear view into your home, but still lets light into the basement. Ordering and installing a glass-block window is a straightforward process within the capabilities of most homeowners who have a few do-it-yourself home improvement projects under their belts.

Things You'll Need

• Tape measure
• Circular saw
• Pry bar
• Eye glasses
• Gloves
• Wooden block
• Screws
• Screwdriver
• Wedges
• Mortar
• Trowel

Instructions

1. Measure the height and the width of the window opening with a tape measure. Measure to the foundation wall, not the current window framing. Select a pre-assembled window that fits within the rough opening measurements. Purchasing individual blocks and assembling the window creates more work than necessary, since you can purchase the window pre-assembled to your measurements.

2. Take the measurements to your local home improvement center or your local window supplier and place the order for the glass block window. You can select from many different finishes, such as clear, colored or mirrored. Select a finish that suits the style of your home.

3. Cut through the existing window jamb with a circular saw and then pry the old window framing out of the foundation with a pry bar. Protect yourself with gloves and eye protection while completing this task.

4. Attach a wooden block into the top of the window opening to prevent the glass window from falling into the basement. Position the block far enough back that it allows the full width of the window to fit into the rough opening. Use a screw and screwdriver to secure the block into the rough opening. The wooden block is temporary and you will remove it later.

5. Cut three triangular wedges out of scrap wood or purchase three triangular wedges from a home improvement center. The wedges help you line up the window.

6. Place the block window into the rough opening and then place a wedge between the bottom of the rough opening and the bottom of the window. Place a wedge on each side of the window as well.

7. Move the wedges in or out until the window is centered from top to bottom and from left to right inside the rough opening.

8. Apply mortar into the spaces between the window and the rough opening with the trowel. Do this on both sides of the window. Stay away from the wedges. Allow 24 hours for the mortar to dry

9. Remove the temporary wooden block from the window.

10. Remove the wedges and then fill in the voids left by removing wedges with mortar. Again, allow 24 hours drying time.

Tips & Warnings

• Call or email a glass block window specialist for specific technical advice

References

• Family Handyman: Installing Glass Block Basement Windows