Chicago’s Proposed Bird-Friendly Building Ordinance: What It Would Require

What would Chicago’s bird-friendly building ordinance require?

As introduced on March 18, 2026, Chicago ordinance O2026-0024083 would add a new Chapter 13-150, Bird-Friendly Building Design, to the Municipal Code. It would require 100 percent of the glazing within 100 feet of grade to be bird-friendly material on new construction and on renovations that replace 25 percent or more of a building’s glazing or add new glazing. It would also cover certain high-risk building features and free-standing glass structures, and it would apply to permits applied for beginning January 1, 2027.

The ordinance has not been adopted. As of October 9, 2026, the City Clerk’s record shows it in committee, with no committee hearing or Council vote recorded. Its requirements could change before any vote.

Where does the ordinance stand right now?

The City Clerk’s legislative record for O2026-0024083 shows this history:

• March 18, 2026: introduced by Alderperson Maria Hadden (49th Ward) and referred to the Committee on Committees and Rules.
• July 15, 2026: discharged from that committee on Alderperson Hadden’s motion and re-referred.
• Current status: in committee before the Committee on Zoning, Landmarks and Building Standards.

The record lists 21 sponsors and co-sponsors. A committee would have to hold a hearing and recommend the ordinance, and the full City Council would have to pass it, before it became law. We will update this article when the record changes.

Which projects would the ordinance cover?

The ordinance defines a bird activity zone as the area from ground level to 100 feet above grade. Within that zone, 100 percent of glazing would have to be bird-friendly material on:

• All new construction
• Renovations or additions that replace 25 percent or more of a structure’s existing glazing or other transparent or reflective materials
• Renovations or additions that add any new glazing or other transparent or reflective materials

Two categories would be covered whether or not the rest of the project is. Auxiliary structures are free-standing or highly reflective structures such as glass railings, noise and wind barriers, and transit or weather shelters. High-risk building features are skyways and skywalks, every floor of a building connector, exterior corners where a bird may perceive a fly-through condition, interior corners, glazing next to courtyards, atria, and the first three floors of glazing next to a green roof, amenity deck or roof terrace. The corner provisions reach 30 feet from the corner.

The ordinance defines glazing broadly as all types of glass and any other building material that is transparent or highly reflective.

What counts as bird-friendly material?

Under the ordinance as introduced, a glazing, facade material or exterior surface treatment qualifies if it meets at least one of four criteria:

1. A material with an American Bird Conservancy Threat Factor rating of 25 or less
2. Transparent or reflective surfaces with permanent visual markers, patterns, fritting, etching, UV patterns, ceramic inlays, films or other treatments applied to the exterior surface that comply with the American Bird Conservancy Prescriptive Rating Criteria, including its spacing standards, or equivalent criteria approved by the Department of Buildings
3. Surfaces screened, shaded or covered by building features with no gap larger than 12 inches in any direction, such as double-skin facades, metal screens, louvers, fixed shading or mesh
4. Continuous-surface materials such as spandrel glass, opaque or translucent panels, and fritted or etched surfaces whose reflectivity and gloss meet the same American Bird Conservancy criteria

The second criterion is the one that matters most for existing glass. It names films directly, but only films on the exterior surface that meet the American Bird Conservancy criteria. Under the text as introduced, a film applied to the inside of the glass would not qualify under that criterion.

Which buildings would be exempt?

As introduced, the ordinance would not apply to:

• Coach houses, detached houses, townhouses, two-flats, and residential buildings of three dwelling units or fewer
• Renovations, alterations or additions to multi-unit residential buildings of four to six dwelling units
• Buildings designated as Chicago Landmarks, contributing buildings in a landmark district, and buildings color-coded red or orange in the Chicago Historic Resources Survey

Would existing buildings have to be retrofitted?

Not as introduced. The ordinance does not require owners to treat existing glass on a building that is not being renovated. It applies when a project crosses one of its triggers: new construction, replacing 25 percent or more of the existing glazing, adding new glazing, building or replacing an auxiliary structure, or having a high-risk building feature covered by the chapter.

For owners planning renovations, that distinction is the practical one. A project that replaces a quarter of the glass, or adds a new glass entrance or enclosure, would bring the glazing requirement into play if the ordinance is adopted in its current form.

How does this compare with the Illinois bird-safe law?

Illinois already has a bird-safe building law, but it covers state buildings only. Public Act 102-0119 (20 ILCS 405/405-317), effective January 1, 2022, applies to new construction, acquisitions and major renovations of buildings managed by the Illinois Department of Central Management Services, and to renovations that substantially alter more than 50 percent of the facade. It does not apply to private buildings or to buildings the state leases.

For covered state buildings, at least 90 percent of exposed facade material from ground level to 40 feet, and at least 60 percent above 40 feet, must be bird-safe. Qualifying methods include screens and exterior shades, UV-patterned glass, patterns with horizontal gaps under 2 inches high and vertical gaps under 4 inches wide, and opaque, etched, frosted or translucent glass. The law also restricts transparent passageways and corners and calls for shielded, minimized exterior lighting.

Chicago’s proposal would apply more broadly and require higher glazing coverage: it would cover private buildings, apply 100 percent coverage to 100 feet, and use the American Bird Conservancy’s criteria rather than a fixed spacing rule. The ordinance also states that its requirements are in addition to the City’s Sustainable Development Policy, which applies to City-assisted development, and that the ordinance controls if the two conflict.

Where does window film fit?

Exterior-applied bird collision film is one of the ways to make existing glass bird-friendly without replacing it, and the ordinance’s second criterion names films specifically. Whether a given film qualifies depends on whether its pattern meets the American Bird Conservancy Prescriptive Rating Criteria or equivalent criteria the Department of Buildings approves.

AAA Glass Tint installs exterior bird collision products including Solar Gard WingSafe, Feather Friendly surface-applied markers and SOLYX bird film, chosen to meet the project’s specification. On the projects we see, architects and general contractors usually need the exact product and pattern, where it goes on the glass, product data, warranty information, and samples or mockups before they approve a system. Manufacturer warranties for exterior bird film vary by product, so the current warranty document for the specific product should be part of that submittal.

Because bird film is applied to the exterior, access is part of every project. We use commercial lifts and other access equipment as the building requires. Existing buildings are often treated in the zones where collisions occur rather than across the entire facade; under the ordinance as introduced, a covered project would instead need all glazing in the bird activity zone to be bird-friendly.

We cover the products and the installation process in more detail on our Bird Strike Film page.

What should owners and architects do now?

If you are designing new construction or planning a renovation in Chicago that could reach permit after January 1, 2027, watch the City Clerk’s record for O2026-0024083 and plan for the possibility that 100 percent of glazing within 100 feet of grade will need to be bird-friendly. Renovations that replace a quarter of the glazing or add new glazing are the easiest to overlook.

For existing glass, exterior bird collision film can be evaluated now, on its own merits or ahead of a renovation. If you would like a product recommendation and a mockup on your building, the next step is an on site assessment.