Architects in Australia and many other countries around the world are aiming high by looking to completely reinvent the way sustainable housing is designed and built..

New projects are being developed to create affordable sustainable houses, with prefabrication one leading method. The importance of lowering the cost of sustainable construction is critical in encouraging every citizen to go green when it comes to their homes.

Environa, an Australian architecture firm directed by Tony Wheeler and Jan O’Connor, is developing innovative projects on the sustainable building front, including a display home designed to be sustainable and affordable and a prefabricated house that can go completely off the power grid.

In a recent interview with a community radio station in Melbourne, Wheeler acknowledged that green building is currently more expensive than traditional building, but he spoke of creating a better, more economical, more sustainable way to live.

Environa’s display home, designed to be sustainable and affordable, looks similar to a traditional house but boasts a few distinct differences. For instance, instead of a flat roof, the home features s a skillion roof made of a walkable material which is more durable than traditional corrugated steel and allows home owners to build a green roof and/or install photovoltaics on it.

Inside the house, the ceiling is also sloped and showcases exposed brickwork. The materials used in the home’s construction contain low volatile organic compounds, improving air quality. While standard building techniques can be used, such as timber frames, high levels of insulation and reverse brick veneers on the house’s exterior boost its green performance.

This construction system, often used in environmental design, helps to keep unwanted heat out of the building and preserve the thermal mass on the inside, resulting in more stable and comfortable internal temperatures.

Environa is also working on developing a ‘zoning’ concept as opposed to being open planned. This allows the home to be divided into different zones to make it more flexible and to allow up to three generations to live there at once, which each generation having its own space, thereby adding privacy.

Wheeler said zoning, as seen in the design of the E3 Logic House, provides more efficiency than open planned homes as rooms can be shut off, lessening the demand for heating and cooling.

The E3 Logic House –one of the Display home designs- by Environa Studio. Image: light home

The E3 Logic House
by Environa Studio

One key characteristic of green home construction is that houses are being built smaller than traditional homes and feature several outside “rooms” such as courtyards or kitchen garden spaces.

The smaller size makes these houses more energy-efficient as they reduce the need to heat or cool large ‘wasted’ interior spaces, and energy is also saved in lighting costs. In addition, the construction – including the amount of materials and energy used throughout the building process – and the impact of the building on the surrounding environment are reduced.

In another development in the sustainable construction realm, prefabricated models designed to go off grid are being designed. Some of these have already been built in Australia and there are more under construction. These models can be built using a tractor instead of a crane, which makes transportation and building easier and lowers costs.

“You pull it off the back of a truck and position it on the ground. You can have a home delivered from one truck, with a maximum size of 65 square metres, so that is a one bedroom home with everything in it, enough for two people or a young couple with a child,” Environa explained. “When the family grows, you can add another module.”

Furthermore, a separate module can be added providing solar water heating electricity, batteries for backup power and sewerage capabilities, allowing the house to be self-sustaining.

Designed as well to be affordable and sustainable, the Illawarra Flame House, which won the 2013 Solar Decathlon China 2013, saw an existing Australian fibro home converted into a house that can produce more energy than it uses. The materials used to build the Illawarra Flame House were low in VOC content and came primarily from recycled sources.

The main changes to the original house included making it more airtight, enlarging its windows and installing vertical gardens, a photovoltaic thermal air system and a rainwater harvester. In addition, an open plan living and dining area helped to increase natural lighting and ventilation.

Projects like the Illawarra Flame fibro house could represent a huge step toward a sustainable and affordable future for the residential housing sector as it demonstrated existing houses can be made energy efficient while remaining comfortable.