So much more than a means to access to light and views, modern window systems play a crucial role in insulating our interiors from environmental factors. AGP’s Brendon Peterson explains.
Interview by Simon Farrell-Green. This piece was originally published in HERE magazine.
Here: Why is glass so important now?
Brendon Peterson: Glass is not simply something that fills a void in a wall to keep the rain and wind out: it is now an insulation and light-controlling product that should be specified with appropriate consideration to the desired outcome. With building codes constantly increasing, the performance required from technology in glass is more important now than ever.
H: What sort of effect can good glass have on the design and performance of windows?
BP: Glass makes up the majority of the surface area in a window or door, so it is the critical material to influence total system performance. High-performance glass allows us to maximise light transmission into a home, while regulating heat loss in winter and heat gain in summer. This means we can rely on passive heating and cooling, which significantly reduces power bills and emissions. It also means we can maximise the amount of glass used in our projects, allowing for larger windows.
H: We talk a lot about heating and cooling, but what are some other impacts?
BP: Good glass also means acoustically sound and airtight. The way humans live and work has evolved over time and as cities become more densely populated, we are seeing stricter acoustic requirements too. Air leakage and the wrong glass can lead to sound transfer – but the right glass type to combat that transmission can mean peace and quiet in your home, regardless of location.
H: Tell us a bit about low-emissivity glass and why it matters.
BP: We insulate our walls, floors and ceilings – but we are resistant to do the same with our glass because we look through it and not at it. In the past, glass products have been able to achieve high levels of solar control, but only by using reflective tinted glass. Low-emissivity coatings help retain heat in winter and reflect unwanted heat away in the summer, and they’re also virtually invisble, retaining a clear look. Double glazing without low-emissivity coatings can create overheating by trapping heat within a home and increasing temperatures higher than outside.
H: What effect have the recent changes to the building code – the H1 rules – had on glass requirements and how have you addressed this?
BP: H1 has mandated significant improvements in the overall thermal performance of building envelopes. AGP was already offering H1-compliant glass solutions, so it was not a major shift for us. It was more about combining our glass solutions with thermally improved aluminium frames, which again APL was prepared for with the ThermalHeart+ suites. H1 meant that the industry was finally on the same page as what AGP was selling from the beginning. It has also meant that low-e IGUs (insulating glass units) like our Solux coating ranges have become a requirement for compliance.
H: Tell us a bit about the AGP factory.
BP: The factory is a 40,000-square-metre facility located in Cambridge. Our purpose-built building was designed by Jasmax, is climate controlled and has a five-star Green Star rating. The manufacturing equipment layout was designed, then the building was designed around it. It is the largest single IGU-manufacturing plant in New Zealand, and arguably in the Southern Hemisphere. It utilises the most up-to-date glass-processing equipment available globally, with some of the technologies only used in a handful of glass-manufacturing plants in the world. Being climate controlled and well insulated enables consistent manufacturing conditions, which translates into consistent high-quality production.
