Basement Egress Window Requirements in Colorado
March 24, 2026 • Basement Remodeling
If your basement finish includes a bedroom, egress is required. Colorado rules vary by jurisdiction. Here is what Boulder County homeowners need to know.
A basement bedroom requires a code-compliant egress opening: a window or door that provides a direct emergency escape path to the exterior. Without it, the room cannot legally be called a bedroom regardless of how finished it looks, and it will fail the final building inspection. DG Home Pro will not finish a basement bedroom without a compliant egress opening. It is a design standard and an ethical practice, not just a code requirement.
IRC Minimum Egress Standards
Colorado has adopted the International Residential Code with local amendments. The IRC sets the following minimums for egress openings in habitable basement spaces:
- Minimum net clear opening area: 5.7 square feet (4.5 sq ft if the sill is at or below grade).
- Minimum net clear opening height: 24 inches.
- Minimum net clear opening width: 20 inches.
- Maximum sill height above finished floor: 44 inches.
Boulder County Specifics
Boulder County follows the IRC baseline with a meaningful addition: energy code compliance documentation must include the U-factor of any egress window being installed. Boulder County's adopted stretch energy code requires window U-factors of 0.30 or better in most residential applications.
Boulder County also enforces specific window well dimensions for windows at or below grade. The well must be at least 36 inches wide and project at least 36 inches from the foundation wall. Wells deeper than 44 inches require a permanently affixed ladder or steps. D&G includes this documentation in every Boulder County permit package so it is not flagged at plan review.
Jefferson County and Denver Proper
Jefferson County follows the IRC baseline closely, with no significant local amendments affecting egress. Permit approval for a basement finish with an egress window typically runs 3 to 5 weeks. Denver proper has a faster permit process (often 2 to 3 weeks) and is particularly attentive to the 44-inch maximum sill height requirement, which is one of the most common non-compliance findings on Denver basement bedroom inspections.
Egress Window Installation Costs
Installing a new egress window in an existing poured concrete foundation involves cutting the concrete, installing the window unit, installing the window well, and waterproofing the opening. Cost ranges from $3,500 to $6,000 in the current Colorado market, depending on foundation thickness and access constraints. Block foundations cost $2,500 to $4,500. D&G includes egress window installation in the main basement permit package, not as a separate contract.
D&G's Award-Winning Basement Track Record
D&G Home Pro has earned 15 Best of Houzz awards across 10 consecutive years, placing it in the top 3 percent of home professionals on the world's largest remodeling platform. That track record represents a decade of verified homeowner reviews and recognized design work in this market.
Our designers include egress window specifications in permit drawings on every basement bedroom project. We know what each county's plan reviewers look for and document it proactively, which is why our first-submission approval rate is high in Jefferson County, Boulder County, and Denver.
Frequently Asked Questions
Do I need an egress window for a basement bedroom in Colorado?
Yes. Any room in a basement that is used or intended as a sleeping room requires a code-compliant egress opening under the IRC as adopted by Colorado. A window that does not meet minimum size and height requirements will cause the room to fail inspection.
What size egress window is required in Colorado?
The IRC minimum is 5.7 square feet of net clear opening area (4.5 sq ft if the sill is at or below grade), with a minimum height of 24 inches, minimum width of 20 inches, and maximum sill height of 44 inches above the finished floor.