This year Sanctuary magazine will be an official media partner of the State of Design Festival. The Victorian Government’s State of Design Festival is a key element of the Design Victoria Strategy developed to increase awareness of design and showcase how it generates innovation, promotes sustainability and adds value to business and society.

The State of Design Festival reaches an audience of more than 100,000 throughout Victoria over a 12 day period from 14 to 25 July 2010.

Sanctuary magazine will be running a key event in the State of Design Festival.

The event, Speed Dating with Sanctuary, will be held at the Atrium in Federation Square on Saturday 17 July between 2.30pm – 4.30pm.

Speed Dating with Sanctuary is designed to bring architects and designers together for brief but informative exchanges. You will be able to showcase your projects and display banners and corporate material. Designers will each have a table for the duration of the event.

This event will be publicised across Victoria by State of Design organisers, the Alternative Technology Assocation and Sanctuary magazine.

Sanctuary is Australia’s most respected independent green architecture magazine. Sanctuary’s core readership is householders who are renovating, building or planning to build. They are looking for architects and house designers, inspiration and advice to help with their project.

Speed Dating with Sanctuary will brings green architects and house designers together with potential clients in a relaxed “no obligtions” environment where questions can be asked and each party can get to know the other.
Places are strictly limited. To ensure your place in the event please email a brief expression of interest to verity@ata.org.au by March 10.

Sanctuary magazine and the Alternative Technology Association are committed to impartial, independent advice. Your attendance at the event is FREE.

By Helen Norrie and Alysia Bennett

Excerpt: Wanting to build their own homes but reluctant to move to the city fringe to make their project affordable, two Hobart-based families came up with an idea that provides an excellent model for sustainable living – not just environmentally, but also economically and socially. The two families pooled their resources to buy a very steep site on the edge of the inner city, and developed the design for their houses in tandem. This allowed them to share the cost of site works, and to develop a standardised building system that could be utilised in both houses while providing enough flexibility to suit the varying needs of each family.

One of the houses is for Mike Verdouw, a director of 1+2 Architecture, and his partner Julia. The other house is for their friends Daniel and Kylie. Both families have small children, with more on the way. The friends were interested in how they could establish a model of communal living that would provide “an alternative for ordinary families seeking to live creatively in the suburbs”. Each family had a slightly different brief (with Daniel and Kylie wanting to allow the possibility to share their home with a tenant or boarder).

The site was previously an old dumping ground for construction waste, thought to be too steep to be a viable building site. It was overrun with weeds, but had a fine collection of mature Eucalyptus globulus trees to the south and spectacular views to the east. The previous owner had bulldozed a small area at the edge of the site, and this provided a relatively flat zone to manoeuvre cars and to create a shared outdoor living space – for barbeques, Frisbee throwing and bike riding. The houses were placed at either end of the site, arranged to capitalise on the views and to maximise access to any sun that could be found on the south-facing slope.

The steepness of the slope led to a desire to reduce the footprint of both buildings. Each house is double storey, with a modest floor area of 170 square metres. They are both compact rectilinear boxes, with the living spaces on the upper level to reach for the sun and give the impression of living among the tree-tops, while still being connected to the ground on both levels. The efficient plan ensures savings in construction and running costs. Every metre of floor space has been planned to achieve its greatest potential. Bedrooms are reduced to the minimum spatial requirements for sleeping, while the size and number of living spaces is increased. Each house has three living spaces, which allow for a range of uses now and as the families expand, ot their needs change.

By Mara Ripani

Excerpt: The classic Victorian facade of Averil and Florian’s home in inner Melbourne, where they live with their two daughters Jess and Sophie, suggests dark heavy furnishings, copper boilers and wood stoves. But on closer inspection a very different aesthetic and lifestyle is revealed. The contemporary renovation forgoes fusty Victorian for contemporary sustainable chic, while opening its doors to embrace the neighbourhood. The design brief for Steffen Welsch of Steffen Welsch Architects was to create a sustainable home that would support an active and social lifestyle. These objectives were applied through every aspect of the design, from the sustainability features and open spaces to the way the design supports social cohesion and community engagement.

To Steffen, sustainability and an “active” design go hand in hand. “To achieve a sustainable design the home requires active occupants, because it needs to be occupant operated. If you want to shade your house you need to pull down the blinds. If you want to help cool your home, you need to purge heat trapped in the house at night,” explains Steffen. The house forgoes bathroom ensuites for modest size and double glazing, a concrete slab, external blinds, energy-efficient lighting and bulky insulation. The external walls downstairs plaster. While the house has fulfilled its environmental sustainability brief, its social sustainability is also worth noting. The home revolves around a central courtyard, located in the heart of the house. The courtyard offers abundant natural light and ventilation to the bedrooms, as well as the living, dining and kitchen areas. It enables Florian and Avril to supervise the children while they prepare meals and catch up with friends or each other. It creates a dynamic house with adults and children being able to choose alternative routes from the bedrooms to the living spaces, either by traipsing across the courtyard or travelling around its perimeter. And for a close-knit family like this one the courtyard fosters supported independent activities: each member can retreat to his/her own space comforted by the presence of another.

“We like to spend time at home with everybody in the family quite close together, but not necessarily in the same room all the time. The design around a central courtyard with kitchen/ dining and the children’s bedrooms facing it provides us with a sense of being close to each other. This creates a beautiful, peaceful atmosphere,” explains Florian. Along the central corridor each bedroom door is discernible by a different colour. Jess’ bedroom is bathed in beautiful natural light from clerestory windows. A lush purple curtain hangs from the ceiling and when fully drawn it hides a third of the bedroom, creating a more intimate space in winter (a smaller space to heat) and a cubby-like nook to hide in. The bedroom overlooks the front porch and native garden – and most importantly the street – and offers Jess an opportunity to scan the neighbourhood. Steffen recalls a time when Jess glimpsed neighbouring children and excitedly went out to say “come to my house and play with me”. “This was a very positive response,” explains Steffen. “I wanted to create a home that helped connect the family to neighbours and environment. By connecting, you increase opportunities to look after one another and to look after the environment.”

By Alan Strickland with Judy Celmins

Excerpt: Wanting to live sustainably is not a fringe occupation. Millions of Australians want to make a difference to their homes and lives. But as a member of the Alternative Technology Association and an organiser of Sustainable House Day the question I am constantly asked is: “Where do I start?”

Many people come away from Sustainable House Day fired with enthusiasm. They see homes that are warm in winter and cool in summer, without the need for large heaters or airconditioning. They see water-wise homes that gather rainfall and greywater and use these to produce wonderful, food-producing gardens. They want that for their own home. The problem is that visitors only see the finished house. Time doesn’t usually allow visitors to ask the owners about how they went through the whole saga of planning and creating a sustainable home. The wondering, the indecision, the frustration and dead ends, and the many stages of learning they had to go through.

This article aims to help fill that gap. The more you learn before you start, the easier the process will be and the less the likelihood of repeating the mistakes that others have made before you.

Further information

This article is the combination of two online posts at shmeco.com: “I’d like a sustainable home but where do I start?” by Alan Strickland and “Building the self-sufficient dream” by Judy Celmins. Alan Strickland is the Alternative Technology Association’s South Australia Branch Treasurer. Judy Celmins is a director and co-founder of shmeco.com. shmeco.com invites people to exchange their ideas, stories and experience on sustainable living choices. shmeco are managers of Sustainable House Day.

www.ata.org.au
www.shmeco.com
www.sustainablehouseday.com
www.yourhome.gov.au
www.sanctuarymagazine.org.au

By Jenny Brown

Excerpt: Most of the attention paid to sustainable houses these days is on the external envelope: “bricks and mortar”, cladding, roofs, footings, and how it all comes together. Most green home builders and renovators roughly understand the principles of passive solar, cross-ventilation, insulation, rainwater and greywater harvesting. They are aware of the pay-offs to the environment and their hip pocket. As the pundits say, “it’s not rocket science”. But when it comes to fitting out interiors, the knowledge base is murkier.

This is despite interiors being fraught with environmental hazards. So many surfaces, appliances, furnishings, fittings and fixtures coalesce to make up a house interior that it’s not uncommon for a house with great passive design being let down with a poorly thought-through fitout. This is not as it should be. Interior design is where ecologically responsible building gets really personal. It’s been common knowledge for over a decade that sick buildings can have a detrimental impact on human health and psychology. Escalating levels of childhood asthma are being linked with high levels of toxic vapours that “off-gas” from walls, carpets, cabinetry and the hundreds of other household items – most especially when they are new or wet – but in some cases long after their installation.

“Have you ever really smelled a plastic shower curtain?” asks Robyn Galloway. The Melbourne-based designer and founder of ESO, the Environmentally Sustainable Objects Group says there are so many VOCs (volatile organic compounds) in modern consumer goods that in enclosed spaces their potentially toxic gases can recombine in ways that haven’t yet been calculated. Some VOCs are natural. Others, end products of petrochemical chains, are manifestly unnatural. “Some buildings,” says Ms Galloway, “take 10 years to stop off-gassing because VOCs are contained in formaldehyde, glues, standard particle boards, solvents, paints, timber sealants, vinyls, plastics, in household cleaners…in almost anything you can name. Without question we’ve been living in toxic environments.”

“VOCs,” says head of interior architecture at the University of New South Wales, Dr Kirsty Mate, “are not as dangerous as asbestos but they are listed by the World Health Organisation as human carcinogens”. VOCs, most notoriously present in some compressed timber fibre boards (aka particle boards), are just one of the known hazards pushing responsible sectors of the furniture and interiors industries to rapidly redress their manufacturing processes. “There has also been quite a drive from the general public. The industry is trying to improve its product because it is, after all, connected to its bottom line. Newer particle boards, for instance, have a lower level of VOCs and some have a zero formaldehyde content.”

Though informed designers and manufacturers have been onto greener options since the early 1990s, Kirsty Mate says the revolution currently sweeping through her industry is becoming so entrenched and exciting “that it is one of the most innovative, creative and progressive things happening anywhere”. We’re a long way from when Dr Mate was told by colleagues that “it’s just a fad”. Environmentally-conscious interior design and architecture is also “starting to lose that dowdy image”. There are countless brilliant innovations and ideas being adopted and adapted right across the world. One of her favourites is cardboard kitchen shelving: “It could replace particle board, could last for a few years and it can be recycled”.

By Michael Green

Excerpt: The days of old-fashioned incandescent light are numbered. Incandescents work by heating an electrical element to white hot, and as light sources they make great heaters! They’re cheap to buy, but expensive to run. And being very inefficient, they come at a huge cost to the environment. So much so that in February 2007 the Australian government announced it would phase out standard incandescent light globes.

Since November 2008, Australian shops have only been allowed to sell their preexisting stock. Not included in the first stage of the phaseout, however, is the common halogen downlight – though the writing is on the wall for these too. Halogen manufacturers are working hard to improve the efficiency of their lamps, but it seems likely that these too could succumb to regulation – as well as be outcompeted by a host of rapidly developing, high-efficiency counterparts. The downsides of halogen downlights are so numerous one can only wonder how they became so ubiquitous. They use a huge amount of electricity, producing a lot of heat in the process. Because downlight fittings and their transformers must be able to cool themselves, they can’t be covered by roof insulation, so they reduce the effectiveness of the roof insulation. They are also a notorious fire hazard: in the first nine months of 2009 in New South Wales there were 26 house fires attributed to halogen downlights.

When it comes to low-energy lighting technology, there are two main kinds to choose from: fluorescent lamps – both old-style tubes and newer compact fluoros (CFLs) – and light emitting diodes (LEDs). David Baggs, technical director of Ecospecifier, an eco product database (www.ecospecifier.org), says that when choosing lights it’s wise to remember both colour and brightness. Most people prefer the yellowish glow given off by incandescent globes. “To get a light that has the warmth we’re comfortable with, ask for ‘warm white’ CFLs or LEDs,” Baggs says. Halogen downlights are also very bad at one of the main things they’re asked to do: light whole rooms. Halogens are task illuminators: they create bright pools of light rather than general illumination; hence designers misdeploy row upon row of halogen downlights to light a single room – sometimes 12 or more – where one or two pendant lamps would have done the job. Most rooms require two types of lighting. General lighting gives all-over illumination. Task lighting is for specific areas, such as desks or work benches. If you know what kind of lighting you require for a particular situation – general or task – you are halfway to efficient lighting. The other half of the equation lies in choosing the right lighting product for your general and task lighting needs.

By Fiona Negrin

Excerpt: When Jenny and Ken downsized to a tiny 1960s brick veneer cottage in leafy Hawthorn, Melbourne, they resolved to give it a sustainable renovation. “It’s been a long-term view of ours to live more responsibly,” says Jenny, “and as we get older, on a limited income, we wanted a design that uses modern sustainable technology and which doesn’t require high running costs.”

One of the key decisions they made was to retain elements of the old house, rather than to build from scratch. “It’s so much better to use what you’ve got, and it’s also nice seeing the old part of the house still in place,” says Jenny. “You’ve got some history within the building.” The original concrete slab was kept because it was in excellent condition in spite of its age. Building designer Andreas Sederof of Sunpower Design explains, “A concrete slab provides up to four days of stable temperatures, regardless of external temperatures. Combined with double-glazed windows and insulation, thermal mass [such as a concrete slab] is at the core of good passive solar design.” Additionally, some of the masonry and 20 per cent of the roof frame was re-used in accordance with the owners’ wishes to recycle materials. “It’s the best use of the building. You save embodied energy compared to pulling down a building and starting again from scratch, and you save money on materials and resources.”

The challenge for the designers was that the house had only partial northern exposure. “The site position was not optimum for good passive solar design, “ says Judy Sederof of Sunpower. To overcome this, Sunpower installed more windows in the northeast and northwest areas than “you might ideally want in terms of heat loss during winter” to open the house up to light and warmth. Adjustable external blinds and sturdy canvas sails were added to all west and north-facing windows to limit the amount of summer sun entering the house, and to maximise winter warmth.

Home owner Jenny says the windows are among her favourite attributes of the renovation. “The big lovely windows frame the gums and wattles in the park next door. It feels like we’ve got picture windows all around the place! It’s very satisfying, and gives the house a feeling of openness.” The house’s sun-friendly orientation combines with design features and modern technology (including solar hot water, rainwater collection, greywater recycling for use in the garden, double glazing on all windows and doors, and hydronic heating) to fulfil Jenny and Ken’s wish list of a sustainable house with low operating costs. “It makes an enormous difference when bills come in,” says Jenny. “The solar panels mean our electricity bills have dropped. Our water use has fallen off enormously thanks to our rainwater tanks. And hydronic heating is much more efficient. Our bills reflect the sustainability and modest upkeep of the whole place.” Jenny is also delighted with the way her home blends with its surroundings. “The best thing about the renovation is we now live in a place that works with the environment, rather than separate from it,” she remarks. That’s partly thanks to the house’s generous allocation of windows, which “gives views of the seasonal foliage and keeps the focus on the wonderful view,” and also through its clever, and siteappropriate, external colour scheme.

By Fiona Negrin

Excerpt: Lilting bird song, stately river red gums and abundant foliage give the impression that we’re far from civilisation. So it’s a pleasant surprise to realise that the local shops and train station are a ten-minute walk away. Gently perched in the landscape, so modest you don’t notice them at first, are eight small homes. Welcome to Munro Court, a sustainable housing development in the old Victorian gold mining town of Castlemaine.

“The idea was to build very small houses with a modern feel but rustic aesthetic; homes settled in Australian bush gardens,” says designer Robyn Gibson of Lifehouse Design. The development was initiated by a local couple, Sue Turner and Don Wild, whose vision was to build a cluster of energy-efficient modern houses that harmonised with the landscape. Social sustainability would be a key criterion, as would the potential for elderly people to downsize in comfort and age in place. Sue and Don teamed up with Robyn Gibson and Paul Hassall of Lifehouse Design, and Sue’s son Sam Cox of Sam Cox Landscaping, to turn the vision into reality.

Although the houses are placed quite close to each other, they don’t have boundary fences, so strategic design was employed to instil a sense of seclusion. “All living areas face onto the sleeping and bathing areas of the neighbouring house, so nobody’s living areas look into any others,” says Robyn. “Additionally, there are screens, earth mounds and plantings between houses to provide privacy.”

Robyn and Paul worked closely with Sam to harmonise the houses with the landscape. The homes, none of which is larger than 150 square metres (the average new home is around 240 square metres), share an unobtrusive colour scheme of soft grey and tan, and are built with natural materials of bricks and timber, including Cypress Macrocarpa reclaimed from farm windbreaks. Remnant old trees frame the plantings, which are all local species. Robyn muses, “The whole court is filled with foliage – you look at the gardens, not the houses”. Thanks to appropriate species choice and generous mulching, the plants have thrived in a climate of increasingly drier winters and hotter summers.

Living at Munro Court are young families, couples and single retirees. One of the latter is Win, who volunteers at the University of the Third Age and enjoys bushwalking. Win wasn’t especially looking for an environmentally sustainable home, but she was charmed by the house. “I walked into this room and I just thought, it’s so beautiful, so full of light. And the finishes, the colours, so much thought has gone into details and the fittings.”

Win also appreciated the house’s roominess. “A small space can be well used. There’s tons of storage. Big windows and high ceilings give a sense of spaciousness. It’s a small house but it feels like a big house because it has the right proportions.” Within three hours of seeing the house, she’d bought it.

Win has since become a convert to sustainable living. “The ecological design isn’t something that I was looking for but I’m totally thrilled with it because it works so well.” In winter, the morning sun pours into her north-facing windows and “ten minutes later, the living room is warm”. Castlemaine is notorious for its extreme temperatures. Win says she looked at old houses but “they had no north-facing windows, and their bi-monthly gas bill was $600. I didn’t want that. This house is efficient to run. My biggest bi-monthly gas bill in winter was $80, and I was never cold.”

To compensate for Castlemaine’s frosty winters, the houses at Munro Court have large, north-facing double-glazed windows and high levels of insulation to keep the heat in. Concrete slab floors help maintain a stable temperature even on the chilliest nights, and gas heating boosts warmth when needed. Summers can be scorchers, but there’s no need for active cooling in the houses because external awnings and pergolas offer shade, while doors and windows can be flung open and ceiling fans operated to move cool air through the house.

Munro Court cheerfully fulfils its brief of social sustainability. Robyn and Win finish each others’ sentences as they list the occasions that bring neighbours together: to have drinks when a new person moves in; to hold fire management meetings; and to participate in revegetation working bees. Residents share responsibility for tending the communal vegie garden, emptying the compost and feeding the chooks. Sometimes they dine together. And it happens entirely organically.

“One of the really nice things here is that there’s no formal organisation for any jobs to be done,” says Win. “People ask me, ‘who owns the chooks? Do you have rosters? Do you have a vegie bed each?’ but it’s not organised like that. People pitch in when they have time and we all share produce. Elderly neighbours who can’t contribute to the garden still share eggs and vegetables from the garden. It’s very pleasing and generous.”

By Stephen Crafti

Excerpt: Barbara and Ian always knew their leafy North Adelaide block had potential. Located on a compact site, abutting a golf course and parkland, they were aware of views that weren’t being taken advantage of. Hemmed in on either side by substantial homes (one heritage-listed), the obvious solution was to extend vertically. “I wanted a separate studio where I could paint and we also wanted separate guest accommodation,” says Barbara.

One of the architects the couple most admires is Glenn Murcutt, which is how they came to commission Troppo Architects. Architect Phil Harris, a co-director of Troppo, had worked with Murcutt. And like Murcutt, Troppo are recognised for ‘touching the earth lightly’, a phrase that’s come to represent lightweight and sustainable architecture. “We didn’t want a concrete bunker. We were interested in using materials that responded to the environment,” says Barbara.

Troppo’s steel-framed house features several materials, including rammed earth, copper cladding and timber. The rammed earth, quarried locally, not only has low embodied energy but creates excellent thermal mass. Combined with good passive design, the rammed earth stores coolness in summer and heat in winter, then releases it when it’s most needed. In the same way, a concrete floor on the ground level absorbs winter sunlight, which it stores and coverts to heat in the evenings.

“Natural light was at the top of our wish-list,” says Barbara. “The last house we lived in was more like a cave.”

“It wasn’t difficult knowing which direction to move. It was obvious we needed to take advantage of the northern back garden, as well as the views directly ahead,” says Troppo’s Cary Duffield. As Barbara and Ian don’t want to contemplate moving later in life, there are two bedrooms on this level, including the main. “Considerable energy goes in building a house. We didn’t see the point of starting over again down the track,” says Barbara.

Pivotal to Troppo’s design is a connection to the rear courtyard-style garden. Large bi-fold doors open to a deck. And a pond frames the main bedroom. Rather than simply frame the neighbour’s wall from the main bedroom, Troppo included low-level windows to frame the pond and high level celestial windows to capture the sky. The pond not only moistens and helps to cool the air, but it also animates the living areas, with the lounge also enjoying the play of water and light across the ceiling. “We’re only a short stroll from the city. But this feels like an oasis,” says Barbara.

The kitchen, which forms part of the open-plan living areas, was also conceived to “touch the earth lightly”. There are no handles on the kitchen cupboards (considered a superfluous detail) and appliances were chosen for their energy efficiency.

Cross-ventilation was also paramount. As well as large stackable doors to the rear deck, Troppo included ceiling fans for use in the warmer months. And rather than divide spaces with walls, the home is opened up as much as possible. Barbara’s studio, located on the first floor, overlooks the living room and through to the garden. “We wanted to make the garden feel like another room. There’s a blurring of lines between the indoor and outdoor spaces,” says Duffield.

There are photovoltaic cells on the roof for heating and underground water tanks to collect water for the garden, as well as for use in the bathrooms. Although it may have been tempting to orientate the house towards the golf course, Troppo preferred to orientate the house to the north to maximise the light. Ultimately this house operates on a number of levels, says Duffield: “It’s a comfortable house for two, but family and friends can easily fit under the one roof”.

By Michael Green

Excerpt: Windows might be transparent, but they’re complex. Good windows well placed will help keep your home comfortable all year round. Bad windows in the wrong places will cost your dearly.

In a typical insulated house, windows cause more heat gain or loss than any other part of the building fabric. While they’re expensive up front, they’re also an investment in the resale value and day-to-day comfort of your home.

So which windows should you choose? There are hundreds of products and combinations to consider, from the glazing, frames and coatings, to the size, shape and location. The Window Energy Rating Scheme website (www.wers.net) lists detailed ratings of over 40,000 products.

Two years ago, Alan Kerlin designed his sustainable home in Canberra. Afterwards, he established a consultancy, Solar Flair, to help pass on what he found out. When he was researching windows, he found good advice hard to come by. “It’s a difficult area, but it’s easier if you understand some of the basics behind the science,” he says.

Heat transfers in different ways – for windows, you’ll need to consider “conduction” and “radiation”. Conduction refers to the ambient warmth that passes through the glass and the frame. A window’s conduction is measured by its U-value. The lower the U-value, the better its insulating qualities, and the better for your energy bills.

Radiation, in contrast, refers to heat transferred when sunlight passes through the glass, hits something and warms it up. Light is converted into heat as the visible light is absorbed by a thermal body and re-emitted as long-wave or infrared energy – heat.

Radiation is measured by the window’s Solar Heat Gain Coefficient (SHGC); the higher the SHGC, the more radiant heat it lets through.

Passive solar design
Armed with this knowledge, you need to consider the weather where you live and the design of your home. Most Australians live in climates where we want to draw in extra warmth during the cold months and shut it out throughout the hot months. With careful consideration, your windows can help this happen – together with other elements of passive solar design, such as shading and orientation.

In Canberra, Kerlin designed his home with a bank of glass to the north – the sun streams in throughout winter, but eaves and shading block the direct rays in summer. Small windows to the south, east and west help reduce the solar access when the sun is low in the sky and passes below the awnings. “But remember: it all depends on where you are living,” he says. “In northern Australia, you don’t want sun hitting your glass at all.”

Insulating glazing units (IGUs)
No matter your location, there is one constant: double glazing is always preferable to single. For now, nearly every Australian home has single-glazed windows. “They’re like a thermal wound in the building envelope,” says Gary Smith, from the Australian Window Association.

Double and triple glazed windows – known as IGUs (insulating glazing units) – help seal the wound. “Standard double glazing can reduce conducted heat transfer by about half,” Smith says. Triple glazing is common in Europe and North America, but rare here. The window units weigh and cost more, but provide extremely low U-values and excellent sound proofing.

Within an IGU’s frame, the panes of glass are held apart by a spacer. A wider gap gives better insulation – 12 mm is regarded as the best. Likewise, an IGU will prevent even more heat transfer if the cavity is filled with an inert gas, such as argon, rather than air. “With argon, you get about a 15 per cent improvement in U-value,” Smith says.

IGUs also perform strongly in bushfire attack conditions. “Double glazing works really well in the bushfire tests because the insulation barrier stops the radiant heat coming through the glass,” he says. This year, all states and territories will introduce a new standard for windows and doors in bushfire prone areas. So far, few products have been tested to the top levels.

Smith says the extra cost between single and double glazing can be between 50 and 100 per cent, depending on the company and the product. Householders can spend from a few thousand, to tens of thousands of dollars extra. “There’s a huge variance. The best bet is to shop around – there are good deals and really good products out there.”

Glazing
Glass is no longer just plain old glass. It now comes in a dazzling range of coatings and tints that will help keep your energy bills down.

Low emissivity (low-e) glass has a transparent metallic coating that reduces the pane’s U-value. “Low-e glass can significantly reduce the amount of heat that travels through your windows, keeping your house more comfortable in both summer and winter,” says Jamie Rice, vice-president of the Australian Glass and Glazing Association. It can also curtail UV light and reduce fading in furnishings.

Single-glazed low-e coated glass is a good option for people who want a step up from standard glass but can’t stretch their budgets to double glazing. However, it’s far more effective when placed inside an IGU – it can reduce the U-value of a double glazed window by half again.

Tinted glass cuts the heat transmitted into the home from direct sunlight. Available in a range of colours, tints are especially suited to west-facing windows that receive direct, summer afternoon sun. “The problem with standard tints has been that to improve the performance you end up cutting out light,” says Rice. “But there’s now a more sophisticated product, called spectrally selective tinted glass, which significantly increases solar control and only slightly decreases light transmission.”

Low-e coatings and tints can be used in combination. Together, they reduce both the U-value and the SHGC, making for a window that’s ideal for keeping out the heat.

Frames
Most window frames in Australia are made from aluminium. They’re cheap and versatile, but conduct heat very easily, which means they slice the insulating performance by up to 30 per cent. Thermally broken aluminium or composite frames offer better insulation, but they’re much more costly and, for the time being, not widely available.

Timber frames also have significantly lower U-values than aluminium. Edith Paarhammer, from Victorian window manufacturer Paarhammer, argues that although timber is more expensive, it performs better than any other framing material.

She recommends that eco-conscious buyers choose products made from either plantation timber or Forest Stewardship Council (FSC) certified timber. “It’s also very important that the frames are substantial, not flimsy,” she says. “And make sure they have seals all around, so there are no draughts.”

Another high performing frame is uPVC. Only recently introduced into this country, it has a comparable thermal performance to timber, but is cheaper. Warren Miles from Ecovue says a double glazed uPVC window can cost just 25 per cent more than equivalent single glazed aluminium.

Miles says it’s crucial that buyers look for frames that minimise air leakage. “You need a complete seal between the window and the frame, and also between the frame and the structure of the building. If you can’t achieve that you may as well not worry so much about the glazing.”

Miles says it’s crucial that buyers look for frames that accommodate double glazing while also minimising air leakage. “You need a complete seal between the window and the frame, and also between the frame and the structure of the building. Reducing air infiltration is a significant part of energy efficiency.”

Few businesses are specialist window installers, although some manufacturers can do the job. You can find them listed on the Australian Window Association website (www.awa.org.au).

Retrofitting
If you’re in an existing house and want to improve your windows, you have several options. The most effective and expensive way is to remove and replace the entire window units. In some systems you can replace the glass alone.

It’s also possible to retrofit double glazing, either with glass secondary window systems or cheaper acrylic panes that attach to your window frame using magnets. Cheaper still (but less effective) is Clear Comfort, a membrane that you tape to the window frame and make taut by shrinking with a hairdryer (a 10-metre kit costs only $180).

Films are an efficient way to cut solar heat gain on existing windows. They range from almost transparent to dark grey and cost between $60 and $100 per square metre, installed. They are also available with low-e coatings.

Glossary of terms
U-value: the measure of a window’s heat conduction. High insulating windows have U-values from about 3.5 down to 1.4. U-value is the inverse of the R-value.

SHGC: Solar Heat Gain Coefficient. The measure of the heat transmitted through the window when the sun strikes it directly; 0.8 is high, 0.2 is very low.

IGU: Insulating Glazing Unit. Double or triple-glazed window systems, which have sealed cavities between the glass layers.

Low-e glass: glass with a low-emissivity, metallic coating that improves its insulating qualities. Some low-e coatings also reduce the SHGC.

Spectrally selective glass: glass that allows lots of light in, while cutting out unwanted UV and solar heat gain.