Glazing for year-round comfort

Leo Pyrah, product manager at Pilkington UK, outlines the glass specifications that can help commercial buildings to increase comfort and improve sustainability.

Commercial buildings like big office blocks or retail centres typically need more power to keep warm in the winter, or cool in the summer, due to their open plan layouts.

As such, commercial spaces need to be specified with the correct building materials that provide insulation in winter and prevent excessive solar gains in the summer, to help curb energy use, and bring down heating and air conditioning bills.

More than 25% of heat from public buildings escapes through windows, so specifying the right glass can make a big difference in maintaining a comfortable internal climate year round, while minimising energy use and carbon emissions.

Heat loss is normally measured by the thermal transmittance or U-value, usually expressed in W/m2K. Essentially, the lower the Ug-value, the greater the thermal insulation of the glass.

Ordinary clear, uncoated glass has a Ug-value of around 5.7W/m2K. Low-emissivity glass such as Pilkington Optitherm S1 Plus, can achieve a Ug-value as low as 0.5W/m2K in triple glazing.

Low-emissivity glass has a microscopically-thin neutral coating that dramatically reduces heat transfer and reflects interior heat back into the building, retaining warmth internally by preventing it from escaping through the window.

However, commercial buildings need to maintain a comfortable temperature throughout the year, something that can be achieved by specifying a solar control glass that combines solar control and low-e properties.

Pilkington Suncool is a coated high performance solar control glass that can contribute towards a building achieving sustainability certification such as LEED and BREEAM. It is designed to ensure buildings don’t overheat during the warmer months and helps to reduce the need for both cooling and heating systems.

It works by controlling solar heat gains while maintaining high levels of natural light without reducing internal light levels. As a result, it provides optimum performance, in turn enabling extensive use of glazing while ensuring a comfortable year-round environment, which also helps to reduce energy usage.

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