Egress Windows

Egress windows allow you to finish your basement or attic so that the space is livable and flows seamlessly from the rest of the house. This added square footage, bedroom and living space adds tremendous value to Seattle area homes. Local building codes require egress windows in order for a basement or attic room to be considered a bedroom.

When adding egress windows to your basement you can dramatically increase the amount of natural light your basement receives, making the space more livable. If you decide to finish your basement, ask about how Green Built Northwest can maximize light through your basement floor plan. We can help design the layout of your basement to allow for light flow by avoiding too many walls and closed off spaces and helping you consider the location of your windows before deciding where those walls will go. 

Couple and Builder

International Residential Code (IRC)

What are the size requirements for an egress window?


According to International Residential Code (IRC), an egress window must satisfy four criteria:
Minimum width of opening: 20 in.
Minimum height of opening: 24 in.
Minimum net clear opening: 5.7 sq. ft. (5.0 sq. ft. for ground floor).
Maximum sill height above floor: 44 in.


The window must have a minimum net clear opening of 5.7 sq. ft.  Net
clear opening refers to the actual free and clear space that exists when
the window is open.  It is not the rough opening size or the glass panel
size, but the actual opening a person can crawl through.


The window opening must be operational from the inside without keys or tools. Bars, grilles and grates may be installed over windows but must be operational without tools or keys and still allow the minimum clear opening.

Green Built can quickly and easily help you specify which windows meet national and local egress requirements of your windows. This should take the guesswork out of selecting a window for your addition or remodeling project. 

Seattle Egress Window Rules


Emergency egress rules as per WAC


 - Every bedroom or other room designed expressly for sleeping purposes must have a window that meets the minimum requirements of at least 5.0 square feet of opening for emergency egress.
 - Rooms that have a door, with a minimum clear opening of twenty-eight inches wide by seventy-two inches high, which opens directly to the outside do not need to have an emergency egress window.
 - Windows and devices must be installed in a manner which allows for proper operation.
 -  The bottom of the opening of an egress window shall be no more than thirty-six inches above the floor.


Note: In some cases, the height of the bottom of the window can be increased to forty-four inches when the clear net area is increased to 5.7 square feet of opening.

Window Wells

If you're egress window is in the basement, you will likely need a window well to meet egress rules and allow for exit from the home. Green Built is the local leader for installing window wells. To learn more about window well options and the brands we carry, click here.

If you'd like to see some of our egress window with window well installations, check this out!