Basement Bedrooms Start With the Window

A bedroom is an egress question

Adding bedrooms is the most common reason families finish a basement. But a basement room is only a bedroom if it has an emergency escape and rescue opening, a way out that doesn't depend on the stairs. That's usually an egress window with a window well outside.

So the real question isn't "how many bedrooms fit?" It's "how many walls can take an egress window?" Answer that first and the bedroom count follows.

The requirements in brief

Under the 2021 International Residential Code, which Utah has adopted, an emergency escape window in a basement needs:

Net clear opening

At least 5 sq ft when the opening is within 44 in. of outside grade, otherwise 5.7 sq ft

Opening size

At least 24 in. high and 20 in. wide

Sill height

No more than 44 in. above the floor

Window well

At least 9 sq ft, 36 in. each way, ladder if deeper than 44 in.

The full details, including ladder rules and covers, are in our basement egress requirements guide.

Where egress windows can go

• Clear ground outsideA well needs room. Decks, patios, driveways, AC units, meters and property lines can rule a wall out.
• Existing window openingsEnlarging an existing opening is often simpler than cutting a new one.
• Foundation structureA new or larger opening needs a proper header and the right cutting method.
• DrainageWells need a drain path and grading that sends water away from the house.

On a sloped lot, a walkout or daylight wall may provide egress with a door or a window at grade. See walkout basements.

Planning bedrooms around the windows

• Mark every room you might ever use as a bedroom, including future ones, and give each a compliant window now. Retrofitting later costs more.
• Pair bedrooms with a bathroom along a shared hallway, not through another bedroom.
• Size the room for the window wall. Furniture, closet and door placement all work around the window.
• Remember the other bedroom rules, like smoke alarms and ceiling height, which are checked at inspection.

What egress windows cost

This Old House reports an average of $4,216 for an egress window, with a typical range of $2,718 to $5,878 (updated June 2026). HomeGuide lists $3,000 to $7,000 including excavation and the well. Lower figures you may see often cover the window alone, without cutting, excavation or the well, so they aren't comparable. Window style, well type, soil and cutting new concrete versus enlarging an opening all affect the price.

Permits

Egress work is permitted and inspected. Cities check window sizes on the plans: Kaysville's basement checklist asks for window sizes, and Farmington's lists the egress opening and window well requirements. See the permits guide.

Choosing the window type

Window style changes how much opening you get from the same rough opening. A casement window swings out and opens nearly its full size, so it reaches the required clear opening in a smaller frame. A sliding window only opens about half its width, so it needs a bigger frame and a wider cut in the foundation for the same clear opening. Single- and double-hung windows have the same issue vertically. The choice affects cost, well size and how the window looks from inside, so decide it with the layout.

How it works

At the free walkthrough, a screened local basement contractor checks your existing windows against the requirements and walks the outside of the house to see where wells can go. The layout sketch then places bedrooms where egress works, and the itemized estimate prices each window.

Common questions