August 25, 2025
Re: Item 4.1 on August 26 Agenda:
City of Mountain View Update to Bird-Friendly Design Requirements
Dear Mayor Kamei and Members of the Mountain View City Council,
On behalf of Santa Clara Valley Bird Alliance, American Bird Conservancy, and the Sierra Club Loma Prieta Chapter, we thank you for your leadership in adopting bird-friendly design requirements and for considering updates that align with the California Green Building Standards Code. Mountain View has been at the forefront of progressive environmental policy, and we applaud the City for working to integrate bird-safety into its building standards.
As organizations dedicated to wildlife and bird conservation, we write to recommend a few key changes to the proposed code (as written in the 2025 California Green Building Standards Code Title 24, Part 11 Appendix A5 SECTION A5.107—BIRD-FRIENDLY BUILDING DESIGN) to ensure it effectively reduces bird collisions and provides clarity for both developers and City staff. If these changes are accepted by the City, Mountain View would adopt an amended version of Section A5.107 to include the following improvements.
Section 1: Glazing
Remove interior-applied films as a compliance pathway. Interior films are not effective for bird collision prevention because external reflections obscure the visual cues for birds. We recommend the City specify that only exterior-applied or in-glass solutions be accepted.
Section 2: Slats, Screens, Netting, Louvers
Remove netting as a compliance pathway, as it can be a hazard and result in the entanglement of birds and other wildlife
Section A5.107.2 Special conditions
Require treatment for any installation of parallel glass conditions such as glass passageways (including skyways, skywalks and building connectors) of any width, since these configurations are particularly hazardous for birds.1
Expand the list of special conditions that require treatment to include the following features:
Atria, open and enclosed,
Glazing adjacent to courtyards,
Three floors of glazing adjacent to any green roof or partial green roof, and
Stand-alone auxiliary structures, such as gazebos, external ticket booths, bus shelters, and any other free-standing glass, plexiglass, or other clear, transparent, or highly-reflective free-standing structure
We appreciate your consideration and look forward to supporting the City in advancing this important update. Please do not hesitate to reach out if we can provide additional technical resources or expertise.
Sincerely,
Shani Kleinhaus
Environmental Advocate
Santa Clara Valley Bird Alliance
Kaitlyn Parkins
Glass Collisions Program Coordinator
American Bird Conservancy
Dashiell Leeds
Conservation Coordinator
Sierra Club Loma Prieta Chapter
1 At a minimum, use the San Jose Citywide Design Guidelines and Standards, Section 3.3.6 Bird Safety, Standard S3. “Use a bird safety treatment on parallel panes of glass 30 feet or less apart, such as skyways, walkways, and other glass building connectors.” https://www.sanjoseca.gov/home/showpublisheddocument/69148/638863711024900000