Windows play a vital role in regulating temperatures of buildings and their overall energy efficiency, whatever the climate. Energy efficiency is not just about preserving heating in homes in winter; it is also about minimising and preserving artificial cooling in summer.
Today, high-performance windows are increasingly gaining acceptance in Australia as rising energy costs are prompting homeowners to consider the role of windows in their homes.
uPVC (unplasticised PVC, or vinyl-framed) double-glazed windows not only perform well in keeping cold out of a building and heat within; they also work to keep summer heat out and the cool air inside.
Well-established in Europe, the UK and US, where they are the dominant window type used, a key benefit of uPVC high performance windows is their ability to balance optimisation of heating and cooling loads with consumers’ desire for greater natural light.
The excellent thermal insulation of the uPVC frames combined with insulated glass units and airtight sealing mean less energy is needed to maintain an ambient temperature within the home, which is reflected in cost savings, lower energy bills and improved levels of comfort. This makes them an ideal energy-efficient and cost-effective solution for Australian homes where homeowners like large areas of glazing and plenty of natural light.
Research by the CRC for Low Carbon Living reveals that 87% of consumers want a home filled with natural light and 85% want a cool home in summer and a warm home in winter. According to uPVC Window Alliance members, higher-performing window systems (where the U value of the window is less than 2.5W/m2K) are now available in Australia that outperform basic double-glazed windows for a similar cost.
Research conducted by Climate Works for a report, Built to Perform: An Industry Led Pathway to a Zero Carbon ready Building Code, published by the Australian Built Environment Council (ASBEC) in July found that double-glazed windows are one of a number of simple measures to improve building performance that would be cost-effective if undertaken today to meet proposed stronger energy efficiency requirements of Australia’s National Construction Code. The analysis found that upfront costs of such measures would be more than offset by the energy bill savings, reduced spend on heating, cooling and ventilation equipment, and electricity network savings.
Modern uPVC windows are made from a rigid and dense material that is used worldwide for a variety of building products. The multiple chamber construction of uPVC windows gives them excellent thermal performance and strength, plus the frames’ low conductivity limits the transfer of heat and cold. uPVC is roughly 1,000 times less conductive of heat than aluminium. Thermal performance is further enhanced by a minimum 12mm air gap in the insulated glazing unit commonly found in uPVC windows.
Advances in PVC formulations, including a ‘tropical’ version for extreme heat and UV, have improved resistance to environmental conditions, such as heavy rain, warping, cracking or splitting, making uPVC windows a sound choice for Australian and New Zealand climates. With high resistance to weathering, salt-corrosion and termites, low-maintenance uPVC windows are also an excellent choice for coastal locations.
Today’s uPVC windows not only perform well, they look good, are available in a range of colours and offer superior security, thanks to advances in hardware and locking systems. Commonly used in Europe, the tilt-and-turn opening system provides great versatility for ventilating the house and ease of cleaning from inside the building. For example, in tilt mode, the top of the window tilts forward into the room venting hot air outside while preventing cool air nearer the floor from escaping. The tilt function allows ventilation at night with the peace of mind of security.
Moving the handle into the next position enables the window to be fully opened like a hinge door, allowing for cleaning or additional ventilation. Also available is a tilt-and-slide system with similar sealing properties to the tilt-and-turn versions, but better than the standard sliding windows, which rely on brush seals (which keep bugs out, but not air).
Quality uPVC windows have a lifespan comparable to that of aluminium and are recyclable at end-of-life. With their in-built thermal-efficiency, they are up to 40 per cent more efficient than a standard aluminium window, making them a worthwhile investment in today’s energy-conscious world.
With more window companies offering uPVC windows in Australia amid a growing market, they are becoming an affordable and sustainable fenestration choice for 21st century living.
The Vinyl Council of Australia welcomes the findings of a new report that shows stronger energy standards in Australia’s National Construction Code can be delivered cost-effectively for new home owners and will help Australia cut its carbon emissions.
The report, Built to Perform: An Industry Led Pathway to a Zero Carbon Ready Building Code, prepared by the Australian SustainableBuilt Environment Council (ASBEC) and ClimateWorks Australia, analysed and identified measures that would be cost-effective in improving the energy efficiency of buildings relative to the upfront investment cost.
By 2030, improvement in Code energy requirements could deliver between 19 and 25 per cent of the energy savings required to achieve net zero energy in new residential buildings through simple, cost-effective measures such as improved air tightness, double glazed windows, increased insulation, outdoor shading, and more efficient air conditioners, hot water systems and lighting.
Although there are upfront costs associated with these improvements, they are small (less than 4% for detached homes) relative to overall construction costs and land prices while providing ongoing benefit for occupants.
“Australia lags other regions around the world in terms of building energy efficient homes” Vinyl Council Chief Executive, Sophi MacMillan said. “All of the buildings being built today will still be in use in 2050, potentially locking in poor performance at a time when much of the world will be at or near net zero emissions if current target projections are met.”
“We are particularly concerned by the continued use of very low performing windows in a country that loves large windows in its houses. Built to Perform is important in showing there are cost effective measures, such as double glazing, we can – and should – be implementing from today.”
The Vinyl Council also supports the proposition in the report that targets and a forward trajectory are set for future Building Code updates from 2019, with a clear and transparent process for implementation and adjustment over time.
“This approach would provide the certainty industries like ours – supplying thermally efficient uPVC windows and other building products - need to innovate and invest, so as to supply the economic products that higher performing buildings need”, Sophi explained. “This will support a rapid and least-cost, national transition to net zero.”
“Built to Perform clearly shows that cost-effective investment can be made from today to deliver long term improvements in residential energy demand and greenhouse emissions.”
Built to Perform provides industry-based evidence that the Code could, between now and 2050, reduce energy bills by up to $27 billion, cut energy network costs by up to $7 billion and deliver at least 78 million tonnes of cumulative emissions savings.
About the report
Built to Perform: An Industry Led Pathway to a Zero Carbon Ready Building Code presents the results of the Building Code Energy Performance Trajectory project, which quantifies the opportunities of establishing a clear, consistent and ambitious long-term plan for the energy requirements in the National Construction Code. The report modelled eight different building types across four climate zones. It investigated the costs and benefits to society of simple energy efficiency and on-site renewable energy opportunities. The analysis assessed upfront costs associated with improvements, as well as benefits from reduced energy bills, downsizing of heating, cooling and ventilation equipment, and reduced network costs.
This report was produced with the generous support of the Cooperative Research Centre for Low Carbon Living, the RACV and dozens of building industry and government partners. The project has been delivered in partnership with CSIRO, Energy Action (EA), Strategy. Policy. Research. (SPR) and the Sustainable Buildings Research Centre at the University of Wollongong (UOW).
The Vinyl Council of Australia is a member of ASBEC and one of the report’s industry partners.
A new house in a Melbourne suburban street has demonstrated that affordable Passive House construction looks within reach in Australia.
Until now passive houses were priced well beyond the means of ordinary Australians, and scared off both builders and home buyers. But retirees Sue and Peter, builder RMH homes, passive house certifier Grun Consulting, and uPVC windows supplier VUE Windows have produced an elegant, spacious home that looks like any normal new build. Unlike those normal new builds, however, the home will produce stellar results in terms of thermal comfort and energy efficiency. In doing so, they have opened the door to more affordable, comfortable, high performing homes in Australia.
The house features an expansive wall consisting of 32.45 square metres of uPVC double glazed windows and doors across the north-facing living and kitchen areas, including openable fanlight windows at ceiling height for purging hot summer air.
The argon filled double glazed uPVC windows achieve excellent insulation value of Uw 1.37 and a solar heat gain co-efficiency (SHGC) of 0.58, allowing winter sunshine to penetrate but not too much solar radiation in summer.
Read the full article about this house, published in Sourceable.net.
The Vinyl Council has updated its industry strategy aimed at facilitating growth in sustainable PVC recycling practices in Australia.
Developed through consultations with members, industry and government, and at the PVC ReSource Summit held in late 2015, the strategy will direct future actions of the Vinyl Council and the sector.
PVC - the third most commonly used polymer in Australia - is recyclable, however, results show that only low volumes of PVC wastes are recovered, largely because most PVC is used in durable products, and less in packaging (which is where most waste and recycling policies and resources are focussed).
The VCA estimates around 66,900 tonnes ofrecyclablePVC product goes to landfill each year. This is wasted material that could be reprocessed into new quality product by Australian workers and firms, improving Australian productivity, economy and the environment.
The VCA and its members are committed to advancing PVC recycling and reprocessing. The updated industry strategy aims to address barriers, to share knowledge, data and expertise and to encourage innovation of reprocessing, product design and recycling capability.
There are six parts to the strategy and three especially form the foundation:
The VCA has established successful vinyl recylcing programs including the PVC Recycling in Hospitals program which is now in place at over 60 Australian hospitlas. The VCA thanks all those who contribute to the success of PVC recycling in Australia and looks forward to working with many to achieve the actions for improved results for Australia's recycling rate, productivity and manufacturing future.