Birds do not see glass. They see what is reflected in it, which is usually sky or a tree, and they fly towards that. It is one of those problems that sounds unsolvable until somebody solves it, and then looks obvious.
The answer arriving now is a pattern laser etched into the surface of the glass itself. The dots are sized and spaced so that a bird reads the surface as something solid, while a person looking out barely registers that they are there. Because the pattern is physically etched rather than stuck on as a film, it cannot peel, fade or come away at the edges. It lasts as long as the window does.
Cardinal Glass Industries launches theirs, called Divert, in the last quarter of this year. It uses a two inch grid, which lines up with the bird safe design standards written into building codes such as New York City's Local Law 15 and the Toronto Green Standard, and it does away with the films, interlayers and separate acid etching steps that earlier solutions needed. Guardian Glass already has one on the market, Bird1st Etch, approved by the American Bird Conservancy.
Two manufacturers, in the same year, both building it into the glass at the factory rather than selling it as a treatment afterwards. That is the moment a specialist product stops being specialist. Once it is a line on a standard price list and a box an architect ticks, it stops being a decision anybody has to fight for and becomes simply how windows are made.
The nicest part is what it asks of the rest of us, which is nothing. Nobody has to change their behaviour, remember anything, or feel bad about their windows. Somebody redesigned the glass, and now the bird sees the window. That is the whole story.
If you are building or renovating, this is a genuinely easy thing to ask your glazier about, and asking is how it gets stocked.
Our short take: Cardinal Glass Industries announced Divert bird friendly glass for launch in the fourth quarter of 2026, using precision laser etched first surface patterns on a two by two inch grid, aligned with New York City Local Law 15 and the Toronto Green Standard. Guardian Glass markets Bird1st Etch, approved by the American Bird Conservancy. Reported in Glass Magazine and by both manufacturers.