How to Install Basement Egress Windows in 5 Steps

egress window
  • 72-120 hours
  • Advanced
  • 400-1,000
What You'll Need
Circular saw with diamond blade
Mechanical excavator
Masking tape
Measuring tape
Hammer drill
Masonry screws
Treated lumber
Spray foam installation
Fiberglass installation
Egress window kit
Exterior and Interior material

Install basement egress windows so that people can escape through the window in case of an emergency. Contact your local zoning office for information on building codes in your area to know the correct dimension for building in your basement.

Building the egress window will not only add safety, but will also raise the value of your home and bring both airflow and light into the basement. This project will require excavation and cutting heavy concrete material around the area you where will be working.

Step 1 - Choose the Location

Choose which part of the wall you think will have the best available light and blend best with the the exterior of your home. Remove everything such as wires, pipes, and other utilities that could block the way. If you want direct sunlight as an option, it is best to position the window to face east or south.

Step 2 - Buy an Egress Window

Buy your egress window at a local retail store. The salesperson will explain the design, size, and price that will fit into your installation. The code for fire safety is to have at least 5.7-sq. feet of opening and a 20-inch width and 24-inch height.

Step 3 - Prepare the Opening

basement walls with ductwork

Use the masking tape to plan where the window will be placed on the interior and exterior of the wall, allowing enough space for the header and wood frame that will be placed around the sides.

Next, use a mechanical excavator like a hammer drill, or hire a professional because it takes a lot of brute strength and experience to handle. Then use the circular saw to cut along the masking tape line on the interior opening. Move to the exterior and cut along the masking tape on that side as well.

If you are not sure whether the tape is aligned correctly, use a hammer drill to put 2 small holes on the bottom corner of where your window is going to be. Dig out and use any other equipment to match the grade of the bottom of the window and allow 8-inches of clearance.

Step 4 - Place the Lumber

With the opening to the window complete, build a frame from the treated lumber according to the instructions that came with the egress window. Screw the masonry screws into the foundation and ensure that they are plumb and level. If your window is larger than 46-inches, you need to attach a header beam for extra support and stability.

Step 5 - Place in the Window

Now that the framing is done, you can shimmy the window into place and start nailing it to the flange and wooden frame. Double check with a level to make sure everything is in place for last minute adjustments, and check to see that the window can open and close.

Once everything is leveled you can use the insulation foam to cover the crevices. Use fiberglass insulation in the larger areas between the frame and foundation as well as between the frame and egress window. Finish the trim both inside and outside of the window.