Window replacement permits, explained

Do you need a permit to replace windows?

Ask three neighbors and you may get three answers, because cities genuinely disagree. Here are four published rules, side by side:

So the same job, swapping a tired double-hung for a new one in the same hole, needs a permit in Culver City and Bloomington, and none in Woodland if the frame stays. The only reliable answer is your own city's.

Why cities care about a window

A permit for a window looks like bureaucracy until you read what the inspector checks. Four rules come up again and again in the handouts above.

Bedroom egress

A bedroom window is an emergency exit. For a new egress window, the residential code asks for^[1][4]:

Replacement windows get a practical exception. In Culver City, a replacement emergency escape window is exempt from those sizes if it is the manufacturer's largest standard size window that fits within the existing frame or rough opening, in the same operating style or one with an equal or greater opening^[1]. Bloomington and Inver Grove Heights apply the same rule under the Minnesota code, and add that the room must not be used for a state-licensed purpose that requires an egress window^[2][3].

The trap is the operating style. Bloomington points out that for double-hung windows, the clear opening height is measured on the lower sash only^[2]. Switching a casement to a smaller-opening slider can quietly shrink the escape opening below what the old window gave.

Safety glass

Tempered glazing is required in hazardous locations: within a 2-foot arc of either edge of a door where the bottom of the glass is less than 60 inches above the floor, next to stairs and landings, around tubs and showers, and in large panes close to the floor near a walkway^[1][4]. Bloomington adds glass within 5 feet of the bottom of a stairway^[2]. Woodland notes that tempered glass must carry a permanent manufacturer's mark; stickers are not enough^[4].

Energy limits

Replacement windows must meet the energy code. In Minnesota, both Bloomington and Inver Grove Heights cap the U-factor at 0.32^[2][3]. In California, the 2025 Energy Code applies to permit applications filed on or after January 1, 2026^[9], and the limit depends on your climate zone: Roseville's 2025 window-replacement energy form, for climate zone 11, lists a maximum U-factor of 0.27 and a solar heat gain coefficient of 0.23, taken from Table 150.1-A^[10]. City handouts written for the 2022 code show older numbers, so check the energy form your city uses now.

Fall protection and flashing

Where a window sill is more than 72 inches above the ground outside, Culver City requires window opening control devices on a replacement window whose sill is less than 36 inches above the floor inside and which opens wide enough to pass a 4-inch sphere^[1]. Every handout also requires installation to the manufacturer's instructions, with new flashing^[1][3][4].

Old houses: lead and historic districts

Two rules apply on top of the building permit for older homes.

Lead paint. Under the EPA's Renovation, Repair and Painting (RRP) Rule, firms that disturb lead-based paint in homes built before 1978 must be EPA- or state-certified and use certified renovators who follow lead-safe work practices^[6]. Window replacement disturbs painted frames and sashes. The rule generally does not apply to homeowners working on their own home, but it does if you rent all or part of it, run a child care center in it, or renovate homes to sell for profit^[7]. Inver Grove Heights asks contractors working on pre-1978 homes for their lead certification number on the permit application^[3].

Historic districts. In Littleton, Colorado, replacing any existing window, historic or not, requires a building permit, and properties on the Littleton Historic Register also need a Certificate of Appropriateness before a window can be replaced^[5]. Repairing existing windows needs neither^[5]. If your house is in a historic district, the design review comes before the window order.

What the city asks for

For a like-for-like swap, the application is light. Culver City reviews most window replacements over the counter with two copies of a floor plan that shows every window being replaced, labeled with the existing and new size and type, the use of each room, and the owner's details^[1]. Changing the size of an opening adds framing details and can bring an energy report or structural plans^[1]. Inver Grove Heights wants an elevation drawing and a section showing the header and the sill height for any change in opening size^[3].

Inspections are short: Bloomington requires a final inspection for like-for-like replacements, and a framing and final inspection for bay or bow windows or larger openings, with smoke and carbon monoxide alarms working at the final^[2].

What it costs

Your permit file lists your city's fee from its own schedule, with the link.

What we prepare

A window permit is small. Skipping it leaves open the questions it exists to answer: is the bedroom window still a way out, is the pane by the stairs tempered, does the glass meet the energy code. The All-in, until approved offer ($399) covers the whole file: your city's rule for your address, the window schedule with egress, safety glass and energy values checked against the code, the floor plan and forms, a review before you file and our follow-up until the permit is issued.

Common questions