In Minnesota, every sleeping room, including a new bedroom in an existing basement, needs an emergency escape and rescue opening. Under Section R310 of the 2020 Minnesota Residential Code, the opening must be at least 5.7 sq ft (5 sq ft at grade floor or below), 24 inches high and 20 inches wide, with a sill no higher than 44 inches. The window well must be at least 9 sq ft.
When you need an egress window
Minnesota's residential code requires basements, habitable attics and every sleeping room to have at least one operable emergency escape and rescue opening. When you create a new bedroom in an existing basement, it needs one. General alterations or repairs to an existing basement don't trigger the requirement on their own, and a new basement bedroom with sprinkler protection is an exception (Minn. R. 1309.0310).
The size rules
From St. Paul's summary of Section R310 of the 2020 Minnesota Residential Code (St. Paul DSI egress handout):
Net clear opening: at least 5.7 sq ft (at least 5 sq ft for grade-floor or below-grade openings)
Clear height: at least 24 inches
Clear width: at least 20 inches
Sill height: no more than 44 inches above the floor
Window well: at least 9 sq ft, with a projection and width of at least 36 inches
Ladder or steps: required when the well is more than 44 inches deep
A new egress window usually means cutting the foundation or enlarging an opening, so check your city's permit requirements before work starts.
Planning a basement bedroom
When we finish a basement with a bedroom, the egress window goes into the plan and the estimate from day one, along with framing, insulation, drywall, electrical and the permits. See basement finishing.
Planning a basement finishing project?
cK Builders gives free estimates across St. Paul and Dakota County. Licensed MN #BC809999.
Does a basement bedroom need an egress window in Minnesota?
Yes. Every sleeping room, including a new bedroom created in an existing basement, needs at least one operable emergency escape and rescue opening under the Minnesota Residential Code.
How big does an egress window have to be in Minnesota?
Per the 2020 Minnesota Residential Code (as summarized by St. Paul DSI): at least 5.7 sq ft net clear opening (5 sq ft at grade floor or below grade), at least 24 inches high and 20 inches wide, with a sill no more than 44 inches above the floor.
How big does the window well need to be?
At least 9 sq ft, with a horizontal projection and width of at least 36 inches. Wells deeper than 44 inches need a permanently attached ladder or steps.