Window Replacement in Chicago, Illinois

In Chicago, swapping a worn window for a new one of the same type, size and shape in the same opening needs no building permit in a residential building up to four stories above grade, according to the Department of Buildings. Changing the window type or size, working in a taller building, or working on a Chicago Landmark can change that, and the city's Express Permit Program is a web-based route for replacements that do need a permit (Chicago Department of Buildings) ¹².

Who may do the work is set by the city: the Illinois Attorney General says general contractors are not required by state law to be licensed, and Chicago requires a city general contractor license for most building work (Illinois Attorney General) ⁶⁸. Chicago's long winters also mean the glass should insulate well ¹²¹⁴.

Does window replacement need a permit in Chicago?

The Department of Buildings publishes a list of exterior work that needs no building permit. In any building, that list includes repairing a damaged window, replacing glass in an existing sash, installing or removing storm windows and screens, and replacing a ground-level window in kind, frame included, as long as no part of the exterior wall is cut away (work that does not require a permit) ¹.

In a residential building up to four stories above grade, or an associated accessory building such as a garage on the same lot, the list also covers repairing or replacing an exterior window or skylight in kind in the existing opening. The city defines "in-kind replacement" as new elements of the same type, size and shape as the old ones ¹. A double-hung window replaced by a double-hung window of the same size fits that description; a double-hung opening refitted with a casement is a different type, so it falls outside the exception.

Two cautions from the same page. The exceptions may not apply to a proposed or designated Chicago Landmark or a property in a proposed or designated landmark district, and work done without a building permit must still comply with all applicable requirements of the Chicago Construction Codes ¹. The page also says work must follow lead-safe work practices, and some work involving lead-based paint may need a form filed with the Chicago Department of Public Health first ¹.

The Express Permit Program

When a permit is needed, the Express Permit Program is the city's web-based route for repair and replacement work. It launched in November 2023, and applicants file, pay fees, check status and see inspection results online (Express Permit Program) ⁴. Its "Exterior Window or Door Replacement" work type covers (eligibility summary) ²:

• Eligible: replacing a window in an existing wall opening, or a skylight in an existing roof opening, in a building up to 7 stories; taller buildings qualify with drawings by an architect or structural engineer holding an Illinois license ².
• Not eligible: a new opening, windows that have or must have fire-rated glass, windows within 10 feet of a fire escape, a window in a wall within 2 feet of a lot line shared with another property in a building over 3 stories, and windows that do not meet the energy requirements of the Chicago Energy Transformation Code ².

The application asks for at least one photograph of the existing condition and an energy and water efficiency compliance form ².

The permit's terms add rules that shape what you can order (terms and conditions) ³. The permit does not allow any increase or decrease in the size of an opening. A replacement window does not have to open the same way as the old one, but a new out-swinging window cannot block an exterior walking path or extend beyond the property line, and the new window must have at least as much glazed area, and in a residential building at least as much openable area. In a residential building, where the sill is less than 36 inches above the floor, the replacement window must include opening control devices that limit the opening to less than 4 inches within 42 inches above the floor, or otherwise meet the Chicago Building Code for new windows. Openable replacement windows 50 feet or less above the ground need insect screens, and openable windows less than 24 inches above the ground need heavy wire screen or hardware cloth against rodents ³.

Why permit answers differ from place to place is covered in do you need a permit to replace windows.

Who may do the work in Chicago

The city's general contractor license page says a City of Chicago general contractor license is required to perform most types of building construction, alteration, repair and demolition work in the city, and the activities it lists include work that needs a building permit and work exempt from one under Section 402 of the Chicago Construction Codes Administrative Provisions. The Express Permit application for windows names the contractor it requires: a general contractor with a Class A, B, C, D or E license, the class set by the total project cost (general contractor FAQ; general contractor license) ²⁵⁶.

There is an owner exception. An individual may act as general contractor without a license for work on an entirely residential property that is their primary residence, with no more than 6 units and no building taller than 3 stories, and only for one property per calendar year ⁵. An owner filing that way uploads an "owner as contractor" form (Form 401) and government ID showing they live at the address ².

Before you sign, ask: is the company's general contractor license active? The city's general contractor lookup lists active general contractors with license type, number, name, address, and license and insurance expiration dates ⁷. Check that the name on the quote matches the record and that the license class fits your job ⁶⁷.

What Illinois does at state level

The Illinois Attorney General says general contractors are not required by state law to be licensed, that municipalities may require permits or have other local requirements, and that roofers must be licensed by the Department of Financial and Professional Regulation (IDFPR) (Illinois Attorney General consumer alert) ⁸.

What the state does set is paperwork. Under the Home Repair and Remodeling Act, a contractor must give you a written contract or work order stating the total cost before starting work over $1,000, and must hand you the pamphlet "Home Repair: Know Your Consumer Rights" (815 ILCS 513/15; 815 ILCS 513/20) ⁹¹⁰. For contracts over $1,000, you and the contractor both sign an acknowledgment form ¹⁰.

The guide to choosing a window installer covers the rest of the vetting.

Landmark districts

If your home is a designated or proposed Chicago Landmark, or sits in a landmark district, permit applications for work on it are reviewed by the Historic Preservation Division of the Department of Planning and Development, which staffs the Commission on Chicago Landmarks. The division says it reviews all permit applications for work involving those properties, to ensure the work will not adversely affect their significant historical or architectural features (Landmark Permit Review) ¹¹.

The commission encourages applicants to seek its advice before filing; a pre-permit submission can clarify landmark requirements and help speed up the review. Staff can provide direction on most projects, while some types of work, such as new infill construction, additions and demolitions requiring City Council review, go to the commission at a public meeting ¹¹. Remember that the no-permit list for in-kind windows may not apply to landmark properties at all ¹. A homeowners association, where one exists, is a separate private check.

Climate and glass for Chicago

Cook County is in ENERGY STAR's Northern climate zone (climate zone finder) ¹³. Under the Version 7.0 criteria, a Northern-zone window qualifies with a U-factor of 0.22 or less and a solar heat gain coefficient (SHGC) of 0.17 or more, or with U-factors of 0.23 to 0.24 paired with an SHGC of 0.35 or more, or 0.25 to 0.26 with 0.40 or more. All qualifying windows also meet an air leakage limit of 0.3 cubic feet per minute per square foot ¹².

National Weather Service normals for 1991-2020 at Chicago O'Hare put the average January high at 31.6°F and low at 18.8°F, with 38.4 inches of snow a year and 5,974 heating degree days against 1,003 cooling degree days ¹⁴. Heating dominates, so U-factor (how fast heat escapes) matters most, and the Northern zone's minimum SHGC lets winter sun help. The U-factor explainer and the article on low-E glass cover the ratings.

Under the Express Permit terms, replacement windows must meet the U-value and solar heat gain requirements of the Chicago Energy Transformation Code, so ask for the NFRC label values of the exact unit quoted (terms and conditions) ³.

What it costs

This article does not give a Chicago price, because none of the sources above publishes one for the city. As a national reference, Fixr reports that window replacement averages about $800 per window, typically $450 to $1,200, a national figure (updated January 21, 2026) ¹⁵. The window replacement cost guide sets several national surveys side by side and explains what moves a quote.

Getting quotes

Get written quotes that name the window, its NFRC ratings, who pulls the permit if one is needed, and the general contractor license number. The article on how to compare window quotes shows what to line up. When you are ready, you can compare quotes from window installers.

About these figures

• ¹ Official record: Chicago Department of Buildings list of window work that needs no permit (residential buildings up to 4 stories, in-kind definition, landmark caveat, code compliance, lead-safe practices), checked October 26, 2026.
• ² Official record: Express Permit Program eligibility for window replacement (7 stories, 10 feet from a fire escape, 2 feet from a lot line in buildings over 3 stories, contractor classes, required documents), checked October 26, 2026.
• ³ Official record: Terms and conditions for the window replacement permit (opening size, out-swinging windows, glazed and openable area, 36-inch sill and 4-inch opening limit within 42 inches, screens at 50 feet and 24 inches, energy code), checked October 26, 2026.
• ⁴ Official record: Express Permit Program overview (launched November 2023, online filing and fees), checked October 26, 2026.
• ⁵ Official record: Department of Buildings answer on when a general contractor license is required (owner exception: primary residence, 6 units, 3 stories, one property per calendar year), checked October 26, 2026.
• ⁶ Official record: General contractor license page (license required for most building construction, alteration, repair and demolition work, including permit-exempt regulated activity; five classes), checked October 26, 2026.
• ⁷ Official record: City of Chicago active general contractor lookup (license and insurance expiration dates), checked October 26, 2026.
• ⁸ Official record: Illinois Attorney General 2024 consumer alert (general contractors not licensed under state law; local requirements; roofers licensed by IDFPR), checked October 26, 2026.
• ⁹ Official record: 815 ILCS 513/15, written contract for work over $1,000, checked October 26, 2026.
• ¹⁰ Official record: 815 ILCS 513/20, consumer rights pamphlet and acknowledgment for contracts over $1,000, checked October 26, 2026.
• ¹¹ Official record: Chicago Landmark Permit Review (Historic Preservation Division staffs the Commission on Chicago Landmarks and reviews permit applications; pre-permit submissions; public meetings for some work), checked October 26, 2026.
• ¹² Official record: ENERGY STAR Version 7.0 window criteria for the Northern zone (U-factor 0.22, SHGC 0.17, equivalent options) and air leakage 0.3, checked October 26, 2026.
• ¹³ Official record: ENERGY STAR county climate zone list (Cook County, Northern), checked October 26, 2026.
• ¹⁴ Official record: National Weather Service Chicago 1991-2020 normals for O'Hare, matching NOAA NCEI station data (January 31.6°F high, 18.8°F low, 38.4 inches of snow, 5,974 heating and 1,003 cooling degree days), checked October 26, 2026.
• ¹⁵ Reported: Fixr national per-window cost, about $800, typically $450 to $1,200 (updated January 21, 2026), checked October 26, 2026.