As the need for finding sustainable solutions grows increasingly urgent across all sectors of society, a debate on whether or not glass should be used extensively in building design has arisen. As with any debate, there are fervent supporters on both sides, with some calling for an absolute reduction in glass use – including, even, a call for reassessing and possibly even removing existing ‘heavily-glassed’ buildings – and others claiming glass to be 100% sustainable. And again, as with any debate, the truth is lies somewhere in the middle.
When building extensively with glass first became popular in the mid-1800s, there was an understanding that these buildings were not practical for ensuring constant indoor temperatures, and were utilised accordingly. With the advent of complex temperature control systems, an increasing number of large glass structures began to see the light of day. And this is where the naysayers gain their argument. As a naturally poorly insulated material, the excessive use of glass in buildings requires a tremendous amount of energy – often supplied through unsustainable means like fossil fuels – to maintain a livable and worker-friendly temperature.
However, this argument fails to take into account attempts to make modern glass more sustainable. Indeed, currently as much as 30% of new glass materials come from recycled glass, and this percentage is likely to increase with time. New building-related glass also includes specifically developed insulation compounds into the material, thereby significantly reducing the previous need for excessive temperature control measures. This, combined with how modern glass can be coated with specific substances to reduce light absorption and/or joined with other sustainable materials to aid with shade and light control, makes glass structures a far more sustainable option than they might have been previously.
As with any building material, then, it is possible to balance glass’s aesthetics with sustainability, as long as due consideration is given to both.