The future is prefabricated

The collapse of Australia’s automotive manufacturing industry has been devastating, with up to 40,000 workers estimated to ultimately lose their jobs.

Yet with a rapidly growing population and cranes dotting our city skylines, a new manufacturing industry is on the cusp of a boom: prefabricated construction.

Researchers at the University of Melbourne are looking at how this burgeoning industry can provide safe, affordable and sustainable housing, while also offering the opportunity for former automotive manufacturing workers to transfer their skills.

The Melbourne School of Engineering is leading a new push to grow the prefabricated sector’s market share within the construction industry from 5 per cent to 15 per cent by 2025, contributing to around 20,000 new jobs and $30 billion of growth. They are supporting this research with large scale testing and training facilities at their recently announced new campus, to be built at Fishermans Bend.

Professor Tuan Ngo, Research Director of the Australian Research Council Training Centre for Advanced Manufacturing in Prefabricated Housing and the Asia-Pacific Research Network for Resilient and Affordable Housing, leads much of this work.

He says Australia has a lot to learn from European countries like Sweden, where prefabricated modular housing makes up 70 per cent of the construction industry.

Extreme weather, in particular long cold winters, can make building outside difficult there, so prefabricated components are created in manufacturing plants instead.

Why prefab in Australia?

Professor Ngo says supply is unable to meet increasing demand in the traditional Australian construction sector. Meanwhile, costs are rising, contributing to the housing affordability crisis affecting many Australians struggling to buy their first homes.

“We are seeing huge demand in the building industry for new techniques that will allow for the development of faster and cheaper construction. The only way to reduce costs is to reduce the cost of manufacturing,” he says.

“The future is going to be prefabricated in terms of infrastructure, so that is why we’re doing a lot of work at the moment to develop our capability in this area.”

Professor Ngo says prefabrication involves three main types of construction:

• Simple elements: Beams, columns or other parts of a structure that have been manufactured to be easily bolted into place onsite.
• Panelised systems: These are used for walls and include elements such as insulation, utilities, waterproofing and external and internal cladding. These components are designed to allow for rapid assembly and flat pack transportation.
• Volumetric systems: Three dimensional modular objects that comprise the floor, ceiling and wall components for a single room.

He says prefabricated components used to be made from similar materials used in traditional construction, primarily concrete and steel, but these could be very heavy, making them difficult to transport and assemble.

“The new generation of prefabricated buildings have lighter and stronger structural components. Prefabrication also offers opportunities to have high performing thermal and acoustic walls, floors and ceilings by combining durable and sustainable materials into systems such as sandwich panels.

“These days, things can be done much more affordably and efficiently in the factory, but at the moment there is still a lot of onsite work taking place in Australia, and that’s why I think quality and safety has been a problem. You can reduce and minimise those risks with prefabrication.”

Professor Ngo says in Australia a lack of available tradespeople often delays the start of construction projects, sometimes for up to one year. But the collapse of the automotive industry means there are large numbers of people now entering the job market with skills that could be easily transferred to prefabrication.

“There simply aren’t enough people working in construction. On top of this, the average tradesperson is about 50 years old. Growth in prefabrication could see people from automotive manufacturing upskilling and retraining.

“They could become a huge asset to the construction industry.”

The benefits of prefabrication

Prefabrication could also make a huge societal impact by providing low-cost emergency accommodation, particularly for homeless people in cities.

“Also, if a large scale disaster happens, we can develop shelters that can be sent to the site and can quickly put together to host thousands of people.

“Prefabricated structures are reconfigurable and movable. They are very versatile. Increased prefabrication could see the time it takes to build a house reduced from around nine months to less than one.”

Prefabrication is also environmentally sustainable, with more upfront planning meaning less waste, less re-work and less material in the finished product.

“Factors can control how waste is processed to maximise recycling - which is not achievable on conventional construction sites.”

Professor Ngo says skilled workers in a controlled factory environment also create better quality work than may be possible on a building site.

“Higher quality work results in better thermal performance, reducing the cost of heating and cooling for the user.”

The University’s new facilities will allow the team to create full scale prefabricated structures that can be thoroughly tested in a one-stop-shop, reducing costs for industry.

It will offer high-level capacity in areas such as fire safety testing for structural materials, wind and cyclone testing using a wind tunnel, as well as acoustic testing to ensure prefabricated materials are better at absorbing sound. Prefabrication researchers and industry will also be able to undertake energy efficiency testing, ensuring prefabricated products have low carbon footprints.

“We will also have increased space to conduct earthquake testing. We will be able to test a full scale house on an earthquake shaker table to see how the structure performs under simulated earthquake conditions,” says Professor Ngo.

“If we can develop a one-stop-shop for prefabricated testing facilities, this will offer a significant advantage to industry, because it will allow them to do everything in one place. They don’t have to send their product to one location to do fire testing and another location to do acoustic testing.”

Banner image: Pre-fabricated house in Maldonado, Uruguay, Leonardo Finotti/Archdaily