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Best Practices for a Bird-Friendly Building
(modified from City of Toronto's rating system)

1. Glass Treatment

Extent of glass treatment applications that will block a bird's view of the interior of a building:
MINIMUM Treat first ten (10) feet of these high danger areas:
  • Lobbies/atriums with interior lighting at night/early morning hours
  • Lobbies/atriums with interior greenery that is visible from the outside
  • Glass that is proximal to external greenery
  • Areas that trap birds between two or three sides of glass/windows such as an alley, alcove, corner of a building, area above a skylight/atrium, etc.
  • Glass"passageways" that appear to be areas that birds could "fly through" to open vegetation/open space on either side
DESIRED Treat all areas of glass up to ten (10) feet above grade
OPTIMAL/BEST PRACTICE Treat all glass for entire building
Type of glass treatment/design:
MINIMUM During designated spring and fall migration season implement temporary treatment of transparent glass with decals, paints, films at a density pattern of three inches or less apart; strategies to mute reflections with external screening/netting, banners, paints, films
DESIRED Permanent treatment of transparent glass with UV coatings/films or frosted/fritted patterns using a density pattern of three inches or less apart; strategies to mute reflections such as angled glass, external screening/netting or awnings
OPTIMAL/BEST PRACTICE Innovation to eliminate all transparency or reflectivity — bird-safe glass!


2. Exterior Lighting

MINIMUM Extinguish or dim display lighting, including spotlighting, decorative, advertising and rooftop lighting, on buildings over forty (40) stories from 11:00 p.m. until sunrise during designated spring and fall migration periods
DESIRED Install efficient shield lighting for all exterior lighting fixtures, including decorative, advertising, and security lighting. Light focused downward, eliminating direct upward light and reducing spill light
OPTIMAL/BEST PRACTICE Eliminate display lighting, including spotlighting, decorative, advertising, and rooftop lighting


3. Building Operations

Interior greenery:
MINIMUM Internal greenery located at least ten (10) feet away from glass without treatment
DESIRED All internal greenery that could be visible from outside shielded or removed during designated spring and fall migration season
OPTIMAL/BEST PRACTICE No interior greenery that could be visible from outside or glass treated with density pattern of less than three (3) inches apart to shield view of interior greenery
Interior lighting (particularly for ground level lobby areas):
MINIMUM Motion sensor lighting or light timers in linkways, walkways, and corridors; "zone capable" interior lighting system
DESIRED Minimize total amount of interior lighting using task lighting, blinds, light switches, and motion sensor lights in individual offices; cleaning operations during daylight hours
OPTIMAL/BEST PRACTICE Eliminate ground level lobby lighting providing only lighting directed to workstations and security areas


4. Site Design

MINIMUM Drain any pools/fountains that are directly below a set of windows/glass surfaces during migration season. Ground level ventilation grates with a porosity of less than 1 inch x 1 inch
DESIRED All ventilation opening grates proximal to windows capped
OPTIMAL/BEST PRACTICE No pools, fountains, or ground level ventilation grates within five (5) feet of windows/glass surfaces


Chicago Bird Collision Monitors 08/12




Chicago Bird Collision Monitors (CBCM) is an all volunteer bird conservation project that operates under the auspices of
the Chicago Audubon Society.


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