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How to calculate glass energy efficiency

Main image: Amazon Spheres, Seattle. Image courtesy of Nick Wright

Glass, as a construction material, is the only way to visually connect the external and internal environment, whilst keeping out heat, cold, wind, dust and rain. But what is possible and can it ever be cost effective?

According to Nick Wright from Nick Wright Consulting, people like to spend money on glamour purchases, vehicles, generators, technology and marble finishes. But they baulk at spending money on adequate, cost-effective, high-quality window and door systems. Notice the term “cost effective”. Surely fancy windows and doors can never be described as cost effective? Let me explain.

Changing weather patterns

The weather patterns are changing – drastically. Weather events are more intense and more frequent, fuelled by global warming caused by greenhouse gases from human activity. Therefore, energy efficiency (XA) became part of the NBR in 2011. SANS 10400 XA describes controls for shading, insulation and air leaks to fenestration – glazed windows, doors and rooflights. To meet this minimum standards, fit for purpose windows and doors are required instead of the poorly performing products common on the market. Bad windows will create excessive heat losses and gains, condensation and hot and cold air leaks, which will wreck your monthly bills or leave you sweating or shivering.

Keep the payback period in mind and understand the numbers

An example –challenge the numbers and plug in your own…

The correct glass and windows can lead to a four-year payback period, high-performance double glazing and has an expected lifecycle of 30 years.

Think of these:

For more information, please contact Nick Wright:
Tel/WhatsApp: 082 808 1452

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