Many Australians still equate prefabricated construction with mass-produced, characterless houses that are not built to last. But one of Japan’s biggest builders of prefab homes has been in Australia for nearly 10 years now. And it can see the tide is turning. Not only are sales of its prefab showpiece growing, but a zero energy house could soon be next to market.
Compared to countries like Japan where high-tech prefabricated homes are considered “houses of the future”, the industry of permanent low-rise volume housing is still in its infancy in Australia.
But Australian attitudes to prefab homes could be changing. According to Sekisui House SHAWOOD product development and manufacturing manager Makoto Ochiai consumer interest in the company’s line of high-tech, prefabricated SHAWOOD homes is on the rise, with 250 homes completed in Sydney alone since the range was first introduced to Australia in 2012.
The last two years have been particularly good for business. He said word of mouth from a existing customers had led to one in two sales of the homes, which are priced between $635,000 to mid-$700s for terrace homes and between $800,000 and $1.2 million for detached single and double storey homes.
The company believes this is a sign that Australians are starting to embrace prefabrication and recognise the benefits of constructing homes this way.
Sustainability is not high on the list, but liveability is
Although the company’s range of prefab homes perform well on a range of sustainability indicators, such as energy efficiency, Mr Ochiai said sustainability was still not the main selling point.
“Sustainable focused practices are still far from mainstream thinking for a majority of businesses, therefore the cost to purchase, implement and integrate such thinking continues to come at a higher cost to the status quo,” he said.
He believes consumer education on the benefits of prefabricated and sustainably constructed homes will help shore up demand and “push our industry into embracing such forms of construction.”
The prefabricated homes leak 65 per cent less air than conventional homes, he said, which makes it easier to maintain a comfortable temperature without resorting to mechanical heating and cooling. So the average SHAWOOD home receives a predicted 6.5 Star NatHERS rating and a BASIX (Building Sustainability Index) rating of 6.5 stars.
The homes also make the most of natural light, which means occupants depend less on artificial light.
The prefabrication element also lessens construction waste.
Professor Mathew Aitchison, director of the Innovation in Applied Design Lab at the University of Sydney, told The Fifth Estate in July that there is currently a large amount of waste – both construction materials and human labour – generated by the construction industry.
He said that waste can be significantly reduced by linking design with a more “considered and rigorous construction system”.
The perks of prefabricated homes
What is more likely to be resonating with home buyers is the quality and liveability of the SHAWOOD offerings.
Comfort and liveability in the houses is addressed across five elements: passive design, thermal comfort, energy efficiency, health and wellbeing and acoustic comfort.
As well as enhanced thermal comfort, a tight air seal also means less noise pollution, with the homes seven decibels quieter than traditional houses when subjected to the same external noises.
Created to withstand Japan’s extreme weather conditions and earthquakes, quality and durability is another priority for Sekisui House.
At the core of each home is a proprietary “metal joint” and laminated timber post and beam structure, which combined with an external cavity wall system, delivers a “distinctive level of precision and a substantial improvement in quality and reliability”.
“The durability of our SHAWOOD system provides a long lasting quality assurance for each house, which will maintain the value as an asset for many years,” Mr Ochiai said.
Most buyers might think they need to sacrifice choice when they opt for prefabricated homes. But according to Mr Ochiai the company offers 20 architecturally designed single and double storey designs to allay those concerns.
Another benefit of off-site, modular designs and construction techniques is the cost of construction is much lower. This makes this type of housing more affordable, without necessarily sacrificing thoughtful design and choice.
- See our story: The future of buildings: product to process
Pursuing global sustainability leadership
In Japan, the company has been a leader in highly-sustainable homes, delivering more than 35,000 Zero Energy Homes (ZEH).
Despite its strong sustainability track record though, the company is only just dipping is toes into ZEH construction in Australia. Work on the company’s first ZEH home outside of Japan – “SHINKA House” – is currently being built in Sydney.
Located in the “centre of a major growth corridor in metropolitan Sydney”, the home has been designed and constructed to be operated at a Net Zero Energy level and 8+NatHERS Star rating.
The company’s first ZEH outside of Japan, Mr Ochiai said SHINKA House will serve as a “talking piece” as the company expands into new markets in the US, Singapore, China and Australia.
“We are confident that with continued education and projects such as SHINKA house the word will continue to spread with prefabrication perhaps one day becoming a prominent feature in the Australian ‘housing scape’”.