Bird Friendly Glass – Prevent Bird Hitting Windows

By | June 8, 2021

There are 9 major migratory bird migratory areas in the world. In addition to threats such as illegal hunting and habitat loss, migratory birds on the way to the city may also accidentally collide with the glass curtain wall  after entering the urban area with high-rise buildings.

Prevent Bird Hitting Windows

Birds are facing threatens from Windows or Curtain Wall

Birds have their own powerful “positioning and navigation systems”, and different birds have different mechanisms for determining their position during flight. Some birds use the geomagnetic field and polarized light to judge the direction, some birds use the stars as “navigation satellites” at night, and some birds use their powerful memories to travel thousands of miles without getting lost.

No matter how powerful the positioning system is, there will be a “signal blind zone”, and the glass curtain wall causes a lot of trouble for the birds.

Bird Hitting Windows

It’s estimated that glass building “kills” more than 360 million birds every year. The British Ornithology Trust estimates that the number of bird strikes against glass curtain walls in the UK is as high as 100 million each year, and one third of them died.

Why bird hitting the glass?

Highly transparent glass is the culprit. Birds in flight are unaware of the transparent glass, and they will often hitting the glass curtain wall or windows during flight. 

bird hitting the glass

Because glass has good reflectivity, it will reflect the sky, rivers and surrounding plants. Birds in flight will mistakenly think that the image reflected in the glass is a part of nature and is real. The scene is judged to be a safe place, so it will fly to the glass without hesitation.

glass without hesitation

The glass will reflect strong artificial light sources around it at night, and it will also strongly reflect sunlight during the day, resulting in dazzling light spots. At this time, the birds that happen to fly by are suddenly exposed to strong light due to their vision. If you lose your way, you will also hit the glass.

glass will reflect

 when some birds fly at high speed to prey on insects or other prey, their visual perception is often weakened, and they cannot make timely and accurate judgments about the external environment, so they are also likely to hit the glass curtain wall and get injured.

Measurements to Prevent bird hitting your windows.

The only solution to prevent bird hitting your windows or your curtain wall ,is to make your glass visible to birds.

Install curtains or blinds indoors so that the glass does not reflect light as much as possible; if the angle is correct, these decorations will not affect the indoor light or the scenery outside the window, At night, turn off lights or else close curtains or blinds,it is very important for birds. 

bird hitting your windows

Install patterned glass, acid etched glass,diffused glass,sandblasted glass,or translucent glass which can reduce the reflective area;

bird hitting your window

(3) Try to remove the plants in front of the windows and put them in places where the birds cannot see from the outdoors, so that the birds will not think it is a refuge or a source of food;

(5) Someone made the glass more eye-catching by printing a white dot matrix ,or stripes on the glass, reducing the effect of reflection, thereby reducing the probability of bird strikes.

Someone made the glass

It is possible to install a single-sided transparent film for the glass, which will not affect people from looking out from the room, but also prevent the birds from seeing the indoor scenery from the outside;

birds of prey patterns

(7) Stickers printed with birds of prey patterns can also be attached to the outside of the window glass to serve as a warning to the birds.

window glass

(8)Window screen or a light net: Attach this at least 2-3” from the window. When the screen or net is taut, birds will bounce off (imagine a trampoline) without getting caught.

birds will bounce off

Bird Friendly Glass

As architectural glass manufacturer,here is bird friendly glass suggestions from our glass experts that is suitable to use in your new buildings.

Avoid using high light reflectance glass.

Most hard coated solar reflective coated glass ,light reflectance is about 15-30%,for example,6mm French green reflective glass ,light reflectance is 34%,crystal gray reflective glass 16%.

Some low-E coating featured with high light reflectance also got high reflective ,most typical is PPG Solarban R100.Visible light reflectance is 32%.

All these high reflectance coatings will have better effect on forming clear and better reflective images.

It’s advised to use medium reflective glass coating,whether it’s solar reflective coating or low emissivity coating,try to keep it 15-20%.

high light reflectance glass

Using frosted glass.

Frosted glass,or translucent glass,is good way to avoid forming clear reflective images and make the lights diffused.The frosted glass include sandblasted glass,acid etched glass,translucent laminated glass,silk screen frosted glass,patterned glass,and even fluted glass.Click here to learn more about frosted glass.

Using frosted glass

Avoid using monolithic clear glass or low iron glass.

Monolithic clear or low iron glass,light transmittance is around 88-91%,which is not bird friend.Bird will ignore high light transmittance ,and hit on glass directly.It’s suggested to use tinted glass with relatively higher transmittance,for example ford blue glass,euro grey glass,crystal grey glass,French green glass.

Silk screen glass with matrix dots or strips.

The matrix dots or strips on ceramic frit glass are usually white color ,this will remind the bird that there’s barriers before,instead of nothing.

Silk screen glass

Using insulated glass with blinds,or we can call it blind glass.

Blind glass is produced with installed aluminium shutters inside the insulated glass,and controlled with manual,or magnetic controls,and even electric control.The shutters ,or blinds in the insulated glass can be raised and adjusted any angle freely.Uses can control the handle to make it fully transmitted,and 0% light transmittance.

Use grill glazed insulated glass &windows.

Grill insulated glass has many options and patterns based on customers windows sizes,the grills is place inside the insulated glass and split the whole window into many small partitions.The typically used white grills can help bird knowing that windows there.

glazed insulated

Decorative glass.

Decorative glass is widely used in Europe,North American countries and work as entrance doors for house.It has many kinds patterns for selection,birds can easily know the pattern and avoid hitting and flying into your house.

Some glass manufacturers such as Guardian ,Ornilux,Viracon  has developed new bird friendly glass with UV coatings.

The Guardian Bird1st UV stripe coating visually signals an impending barrier to birds and helps prevent collisions.The coatings can be seen by bird by people cannot see it.

Ornilux,Viracon

With above methods,we’re sure that your windows will get rid of lost birds.