United Kingdom & Ireland - EN

Bird friendly glass

logo check
Highlights
Performance and energy efficiency

Understand how glass can influence a building's energy and acoustic performance

Applications of glass

Whether you need glass for facades, interiors, homes, or specific applications, we have a solution

Which glass is right

See how the right glass can help improve your quality of life and the beauty of your home

Understand glass

Learn more about glass and what you can do with it.

Design with glass

There’s almost no limit to what you can create with glass.

Build with glass

Glass is the ultimate building element, and can be tailored to each project.

Glass for your home

We’re helping glass inspire more homes than ever before.

Highlights
122 Leadenhall - 'The Cheesegrater'

The 75,000 square metres façade features a curtain wall that is double glazed to allow for a high solar protection on neutral-looking glass.

Fruit and Wool Exchange

The new-build façades are predominately brick-faced, with punched windows to reflect the surrounding context.

Caudwell International

Curved glass, punch windows and precast stone panels make up the envelope on a figure-of-eight footprint.

All our projects

From landmark construction projects to innovative residential builds, this is how our glass can make the difference.

Highlights
Our story

Just as we were in 1932, we're ready to meet the challenges of now and the future

Sustainability

Find out more about how glass can support sustainable design

Quality control

We strive for quality in everything we do

Our company

Learn more about who we are

Help and contact

Highlights
Glass Analytics

Access our comprehensive suite of engineering and analytical tools

BIM objects

Download and use our standardized Guardian BIM content to create project specific BIM files

Seminars and online learning

For anyone who is interested in learning more about glass and its use

Each year, millions of birds accidentally fly into glass windows, doors and facades, with many of these collisions being fatal. As glass continues to make up more and more of the external building envelope, it is likely that the number of birds affected by this problem will increase over the coming years. Building requirements are becoming more stringent across the world, which means architects are now looking for glass solutions that are safer and which help to reduce the risk of bird collisions, whilst still providing the aesthetic and performance attributes that their projects require.

Attempts to reduce these types of collisions have included adding visible shapes or printed dots to the glass – with positive results. However, the appearance of the glass suffers when patterns or dots are printed on the glass.

Why do birds collide with glass?

The two most common causes of birds colliding with glass are its transparency and its reflectivity.

Transparency

The transparency of glass is perhaps the most well known cause of bird collisions. The bird sees the tree, the sky or an attractive landscape through the glass and flies directly towards it, colliding with the pane of glass in the process. This danger is increased as the transparency of the glass increases (and size of the glazed area).

Transparency

Reflectivity

Another cause of bird collisions with glass is reflectivity. The type of glazed surface, the light and the environment behind the glass all determine how strongly and how clearly the surroundings are reflected. If a park environment is reflected, the bird may be deceived into thinking it sees a pleasant location. It flies directly towards it, without realising that this is only a reflection in the the glass. Reflective surfaces placed in the landscape have the same effect.

Reflectivity

Reducing Reflectivity to less than 15%

The degree of external reflection of glass panes and the design of the surrounding environment are critical. Even moderate levels of reflectivity can pose a danger to birds, particularly when the room behind the glass is dark. Reducing dangerous reflections is a challenge because variable light conditions affect reflectivity. How- ever, choosing glass with a low coefficient of reflection is a step in the right direction.

Reducing Reflectivity to less than 15%

Ornithologists1 recommend that in order to reduce the dangers of reflectivity, glass (double or triple glazing) with an external coefficient of reflectivity of 15% or less should be installed. Such glazing is not completely safe, but for particularly large surfaces, it is an economically attractive and acceptable solution that does not reduce visibility compared to patterned glass.

1 “Bird-Friendly Building with Glass and Light”, Hans Schmid, Wilfried Doppler, Daniela Heynen & Martin Rössler (Swiss Ornithological Institute Sempach, 2013).

Guardian Glass Solutions

Guardian Glass offers a range of solutions answering bird friendly glass requirements for double and triple IGUs (insulating glass units) with external reflectivity of 15% or less. These solutions provide architects with the good balance between transparency and reflectivity. Compared to traditional glass solutions that utilise printed dots or visible shapes, Guardian glass solutions provide architects with high performance, optimal light transmission and clear views of the outside environment. Furthermore, these glass solutions offer enhanced aesthetics that are consistent with the rest of the glazed façade, with no additional surface treatment required or costs involved. This means architects do not have to compromise on the appearance of the glass when choosing bird-friendly solutions. Guardian Glass offer a range of products within its SunGuard portfolio that meet the requirement for bird friendly glass.

Guardian System TEA (True Edge Application)

For higher requirements, a marking can be applied at least on surface #2 of the glazing. An ideal solution for this is the enamel Guardian “System TEA” for ceramic printing of black marks directly onto the coating. As this enamel dissolves the coating (and its reflection) a maximum contrast can be achieved when looking from out- side on the glass.

Ornithologists1 recommend that in order to reduce the dangers of reflectivity, glass (double or triple glazing) with an external coefficient of reflectivity of 15% or less should be installed. Such glazing is not completely safe, but for particularly large surfaces, it is an economically attractive and acceptable solution that does not reduce visibility compared to patterned glass.

1 “Bird-Friendly Building with Glass and Light”, Hans Schmid, Wilfried Doppler, Daniela Heynen & Martin Rössler (Swiss Ornithological Institute Sempach, 2013).