Issues associated with peak demand of energy usage together with increased energy costs for the average Australian family have forced both State and Federal Governments to legislate on the energy efficiency levels of new residential buildings. This comes as hot summers place enormous pressure on the infrastructure and ability to supply energy. Comfort levels are difficult to maintain and in the midst of a heatwave operating costs of air-conditioning are exorbitant.

Windows can be one of the biggest problem areas during summer. Over 80 percent of the heat that enters a building does so through ordinary glazing - the path of least resistance for blistering summer sun that filters through uncovered windows. In fact, an unprotected west-facing window single square metre glass emits the same heat as a single bar heater.

Current architectural trends have led to an enormous increase in glazed and window areas. A love of natural lighting, optimising views and the increase in indoor/outdoor living areas have all contributed to this trend.

Over recent years, however, window have undergone a technical revolution and it is possible to have glass in windows that will keep a home up to 10 degrees cooler in summer, without the use of an air-conditioner. Selection of the most appropriate glazing and frame, particularly of western elevations are critical to the overall energy efficiency and thermal performance of every building. This is something that Arup Façade Engineering research can help with.

Ian Koochew, executive director of the Australian Glass and Glazing Association , believes that we need to be more mindful of the effect windows can have on the temperature levels of a home. “Currently, when considering the thermal performance of windows in Australian homes, we have the worst in the western world,” he says. “If we weigh up the economic, social and environmental benefits to upgrade,. They are enormous. And they remain for the life of the building, impacting for many generations to come.”

For more information contact Arup Façade Engineering on

Source: Building Products News.