AviProtek® Bird Friendly Glass
Bird collisions with building glass facades occur across North America and are the major cause of bird mortality, claiming the lives of millions of birds each year. The magnitude of the problem is such that an important trend has emerged across North America to make buildings much more bird friendly.
Glass causes a major threat to birds by its transparency and reflectivity. With vegetation reflected in the glass, birds are not able to distinguish between a real tree and its image. For a collision to be fatal, the distance from the starting point to the glass facade does not need to be greater than just a few feet. Contrary to popular belief, bird collisions are not just a problem during migratory periods… but all year round!
Several years ago, Walker Textures® recognized the need for better bird-friendly glazing options and engaged in extensive research to understand bird behavior and the properties required on glass to minimize the risk of collisions.
Test protocols and experiments to assess the effectiveness of glass surface treatments have constantly evolved in recent years to a point where the need for an industry wide accepted test standard has been recognized. As a result, a new ASTM committee has recently been created to respond to this need.
To date, tests and experiments have highlighted certain key properties for the glass to be effective at preventing bird collisions:
- Visual markers for birds are more effective on the outside surface of the glass as they can be seen from all angles and in varied exterior conditions.
- The geometry and the spacing of the visual markers must respect criteria commonly referred to as the “2x4” Rule: two inches or less of horizontal space or four inches or less of vertical space should be left untreated.