How to Install a Basement Egress Window

Basement egress windows can add value to your home as well as increased natural light and piece of mind should emergency escape from the home ever be necessary. Because installing basement egress windows typically involves extensive soil excavation and the cutting of heavy concrete foundations, it it not really a casual DIY job. An experienced DIYer with construction experience and the help of a partner or two can reasonably expect to complete an installation like this in a day or two.

Things You'll Need

• Circular saw fitted with diamond blade
• Masking tape, level, measuring tape, hammer, nails, masonry screws
• Treated lumber for rough framing
• Expanding spray foam insulation and fiberglass insulation
• Shovels or excavation equipment
• Egress window assembly
• Exterior and interior finish materials

Instructions

1. Choose a location for the window that is easily accessible on the interior and exterior and avoids any utility pipes, plumbing, electrical boxes or other obstructions that cannot be moved or are costly to relocate. Mark out the window size and rough opening required on both the interior and exterior walls with masking tape to use as a cutting guide.

2. Excavate the soil around the exterior window location with shovels or a mechanical excavator for larger jobs. Allow a sloping clearance of at least 10 inches on each side of the window, 6 inches below the window and at least 5 feet of sloping access in front of the window.

3. Cut interior opening along the masking tape line with the circular saw. Move to the exterior and finish cutting out the foundation wall along the masking tape guide. Take care when making the final exterior cuts as the remnant concrete will be heavy and unwieldy.

4. Build out a rough lumber frame for the new window according to the manufacturer's window measurement and specifications. Screw the rough framing into the foundation with masonry screws. Check for plumb and level.

5. Install the window into the rough frame nailing along the window flange and into the rough wood frame. Check for level and smooth window operation. Spray insulation foam into all crevices and fiberglass insulation in the larger gaps between the rough frame and the foundation as well as between the rough frame and the egress window.

6. Patch and finish the interior and exterior trim to match the materials on the balance of each elevation.

Resources

• A great detailed installtion guide with photos.