Mitigating Glass Railings

By John Carley

Bird-safe glass railings at Point Pelee National Park, Ontario. Photo: Garth Riley

All FLAP volunteers and supporters are well aware of the dangers windows present to birds, but all too often we forget about other architectural uses of glass.

You’ve probably seen the ad, or one similar – Undisturbed, natural, beautiful – extolling the virtues of frameless glass railings for your home or cottage.

Nowhere in the ad does it state that these glass railings are bird-killers. The toll on the local birdlife can be extensive. As anyone who has volunteered picking up injured or deceased birds knows, birds cannot perceive glass. Glass railings are especially dangerous, as birds see the vegetation beyond and attempt to fly-through, with, usually, disastrous results. These results happen whether the glass railings are at a cottage deck, an urban park, or a condominium.

The best solution, when planning your residential project, is to select a railing style other than glass ….wood or metal are far superior. If the guards and pickets are open, you’ll have the added benefit of ventilation, and, if you decline glass, you’ve saved yourself all the maintenance that glass requires! If you are bound and determined to have glass panels, then the glass must incorporate visual markers, closely spaced, on the exterior surface of the glass. An overlay of dots, stripes, or patterns at, desirably,  a 2”x 2” (50mm x 50 mm) spacing can be placed on the glass, or the glass itself could be etched or patterned to the same desirable spacing … in other words, some form of “visual noise” that will alert an approaching bird that these railings are obstacles to be avoided. Geometric patterns (grids, stripes) are the most common, but nothing should prevent a free-form or abstract expression of markers!

Photo: John Carley

If you already have glass railings, then at the very least, don’t clean them 😊. A dirty glass panel is more bird-friendly than a clean one! Seriously though, if you have glass railings, then do mitigate the dangerous situation. Do install a visual barrier in front of or on the glass…hanging strips, applied dot patterns, taped stripes, all work, ideally at the 2”x 2” (50mm x 50 mm) spacing. There are commercially available DIY kits, but homemade remedies work can just as well. Despite being in commercial use, the falcon silhouettes are not effective: they leave too much glass unobstructed. Birds react to the overall “visual noise”, not to the specific image of a falcon.

Occasionally I hear someone mention that there has never been a bird collision with their glass railing. To that my reply is doubtful: that person, more than likely, just has never seen the results. The injured bird may have flown off, to succumb elsewhere, or it may have been scavenged by a gull or animal, leaving no evidence of a collision with the glass railing.

It is estimated that up to a billion birds a year are killed in North America in collisions with buildings and architectural elements. Avoiding the use of glass railings would be the most desirable approach, but making your glass railings bird-safe is a simple and easy task. Both solutions have a great environmental pay-back.

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Author Biography

John Carley is now a retired architect, and a Board member of FLAP Canada. John was a volunteer member (the only architect) of the City of Toronto Bird-Friendly Development Working Group, which produced the Bird-Friendly Development Guidelines in 2007, which were later incorporated into the Toronto Green Standard in 2010. John assisted the City in the preparation of a companion document, which, in 2016, was realised as “Bird-Friendly Best Practices Glass”. John was a member of the CSA Technical Committee that established a CSA Standard for Bird Friendly Building Design. Since 1986, John has been Co-Chair of Friends of the Spit, a citizen advocacy group, established in 1977, dedicated to preserving the entire Leslie Street Spit and Baselands as a car-free public urban wilderness.