Field testing—a natural option
Field testing is offered at the Acopian Center for Ornithology. In field tests, the setup simulates how a window will behave when installed in a “human” structure. The windows in the field experiments look (to both birds and humans) exactly as they would look if installed in a building—as a see-through, reflective window. Like in actual buildings, the reflective windows cover a recessed dark interior. This is done because a perfectly clear pane will act like a mirror, reflecting the facing habitat and sky if it covers a dark interior. Most window installations in the built environment result in reflective panes.
This field testing examines the effectiveness of systems by using birds in their natural settings, where they live and move about. Birds are monitored while interacting with systems as they would at any human structure they are attracted to or encounter in their daily movements. Field testing depends on the chance of free-flying birds having a glass panel in their flight path. Feeders are used to increase the odds of the birds flying toward the glass.
Field testing is representative of the conditions during the exposure period and does not assign a threat factor to the rating. However, for manufacturers who want to take advantage of the real-world results of a field test, this may be an option to consider.
Canadian prescriptive guidelines
Canada uses a standard or set of guidelines different from the U.S., which allows both prescriptive and actual tests results to be considered for inclusion on a project. Key elements of these tests are:
- Visual markers should be used in a glazing unit (first surface) to address both see-through and reflective conditions.
- Spacing of visual markers should meet the
“2 x 4 rule.” - Visual markers should meet a minimum size of 3 to 4 mm (0.119 to 0.159 in.), depending on the geometry.
- Visual markers should be in high contrast to the glazing material.
- Visual markers should be used in high-risk collision zones—the first 12 to 15 m (40 to 50 ft) from grade, corners, and floors adjacent to green roofs.
- Visual markers should be considered for glazing on building elevations, balcony railings, ramps, and free-standing glass structures.
The standard, CSA A460:19 was written in 2019, and has not been updated ever since. For manufacturers with emerging technologies, including products which are not placed on the first surface, Canada may be a limited market opportunity and may require special review and approval of test results before permitting the use of a bird-friendly glazing.
Legislation and LEED
The United States Green Building Council (USGBC), which issues the Leadership in Energy and Environmental Design (LEED) certification, points, and credits when buildings achieve specific standards in several sustainable building categories, has also been influential in creating bird-friendly glass and glazing solutions. In 2011, USGBC added Pilot Credit 55 titled “bird collision deterrence” to its Pilot Credit Library. A revised version of the credit in 2015 expanded its availability to all LEED rating systems except neighborhoods. The credit contributes to LEED points with Pilot Credit SSpc55 in Core and Shell.
