UnitedRenewalsGet free quotes
Windows

Egress Window Requirements & Cost

By the United Renewals Editorial Team · Last updated: September 2026

Advertising disclosure: United Renewals is free to use. We may be compensated when you request quotes through our partners, which can affect which offers appear. See “How We Make Money” in our footer for full details.

Under the International Residential Code (adopted, sometimes with amendments, in most U.S. jurisdictions), a bedroom or habitable basement room needs an egress window with a clear opening of at least 5.7 sq ft (5.0 sq ft at grade level), a minimum opening height of 24" and width of 20", and a sill no higher than 44" above the floor. Installing one in an existing basement wall typically costs $2,500–$6,500+, mostly driven by the excavation and well work, not the window itself.

Get free quotes for an egress window installation

Get free quotes

Why egress windows exist

An egress window is a legally required emergency exit — a way for someone to escape (and for firefighters to enter) if the primary door is blocked, most commonly required for any room used as a bedroom, especially in a finished basement. This is a life-safety requirement, not a suggestion: a basement bedroom without a code-compliant egress window can be flagged in an inspection, complicate a sale, and in a real emergency, simply not work as an exit.

The core requirements (verify your local code — amendments vary)

  • Minimum clear opening area: 5.7 square feet (5.0 sq ft is allowed for a grade-floor opening).
  • Minimum clear opening height: 24 inches.
  • Minimum clear opening width: 20 inches.
  • Maximum sill height above the finished floor: 44 inches — so someone can reasonably climb out.
  • Window wells (for below-grade windows) need at least 9 square feet of horizontal area with a minimum 36-inch horizontal dimension, and a permanently affixed ladder if the well is deeper than 44 inches.
  • No security bars or grilles that can't be opened from inside without a key, tool, or special knowledge.

Pro tip from our network contractors

Always pull a permit for a new egress window — beyond being a code requirement, an unpermitted egress window is a real problem at resale, since it can call into question whether a "bedroom" was ever legally one.

What it costs

For a new basement egress window where none exists, expect roughly $2,500–$6,500 or more, and the driver of that range is almost never the window itself — it's cutting a new opening through the foundation wall, excavating and installing the window well, and adding proper drainage. Homes with unusually thick foundation walls, difficult site access, or the need to relocate utilities can push costs higher. If you already have a below-grade window opening that's simply too small, enlarging it is typically less expensive than creating an entirely new opening. See our window well drainage guide for keeping the finished well working properly afterward.

Compare free quotes from vetted local window installers

Get free quotes

Frequently asked questions

Do all basement bedrooms need an egress window?

Under the model International Residential Code, yes — any room used as a bedroom (including in a finished basement) requires a compliant egress window or door. Local jurisdictions can amend the exact rules, so confirm with your local building department.

What's the minimum size for an egress window?

A clear opening of at least 5.7 square feet (5.0 sq ft at grade level), with a minimum height of 24 inches and width of 20 inches, and a sill no more than 44 inches above the floor.

How much does it cost to add an egress window to a basement?

Typically $2,500–$6,500 or more, driven mainly by cutting the foundation opening and excavating/installing the window well — not the cost of the window unit itself.

Can I put bars on an egress window for security?

Only if they can be opened from the inside without a key, tool, or special knowledge — permanently locked security bars or grilles fail egress code because they'd block the emergency exit.

Keep reading

Ready to get windows quotes?

Get matched with vetted, licensed local pros and compare free, no-obligation quotes.

100% free · No obligation · Licensed & vetted pros

Other projects worth pricing

Most homeowners bundle exterior work while the crew and access equipment are already on site — it usually costs less than booking each job separately. Quotes are free and carry no obligation.