Egress Window Installation in Denver
Last updated
Egress window installation means cutting or enlarging a foundation opening, setting a window that opens to at least 5.7 sq ft net clear (5.0 sq ft at or below grade) with a sill no higher than 44 in., and digging a well outside it. IRC R310 sets those minimums. We do the cut, the window and the well. (IRC R310)
What it involves
Cutting or enlarging a foundation opening, setting a code-sized window, and installing a well, plus a ladder when the well is deep.
Code basics
Min. 5.7 sq ft net clear opening (5 sq ft at grade/below grade), 24 in clear height, 20 in clear width, sill no more than 44 in (Arapahoe County / IRC 2021 R310). Full details: code guide.
Permits
Denver requires a permit for new egress windows (source). Landmark/historic properties also need design review (source).
Related guides
- Egress window check: see if your window and well likely meet the minimums Planning the job? See what each window type costs to install, do you need an egress window, egress permit steps and egress window or egress door. We also handle window well installation, window well covers and foundation cutting. For tenants and in-law suites, read about egress for basement rentals and ADUs, and pick from covers that still open from inside.
FAQ
- How much does it cost? → cost guide
- Do I need a permit? → Yes in Denver; see the code guide.
Frequently asked questions
What does egress window installation involve?
Cutting or enlarging a foundation opening, setting a code-sized window, and installing a well, plus a ladder when the well is deep.
How big does an egress window need to be?
At least 5.7 sq ft net clear opening (5 sq ft at grade/below grade), 24 in clear height, 20 in clear width, with a sill no more than 44 in above the floor (IRC 2021 R310, as restated by Arapahoe County).
Do I need a permit in Denver?
Yes. Denver requires a permit for new egress windows, and landmark or historic properties also need design review.
What does a new egress window have to meet?
IRC R310 requires a net clear opening of at least 5.7 sq ft (5.0 sq ft at grade floor or below), a clear height of at least 24 in., a clear width of at least 20 in., and a sill no higher than 44 in. above the floor. Your city may have local amendments, so confirm with your building department.