Prefabricated building technology has come a long way. There are now robots that can put a wall panel together – including put the sheeting such as OSB & plasterboard in place, nail it down and cut off protruding bits – based on a digital blueprint, all without human intervention.
Perhaps most excitingly, the robot systems created by Swedish production machinery company Randek, sort leftover material as they go, resulting in near-perfect waste streams.
The company’s “ZeroLabor Robotic System” attracts a lot of the attention, says Jason Reints, who works at Bliss & Reels, an Australian owned distributor that sells machinery on behalf of the Swedish company.
But the robots are only the top-of-the-shelf option of the company’s behind-the-scenes automation technology that makes offsite construction methods more efficient.
Its automation offerings run the full gamut, from fully robotic systems, down to more mechanical offerings, such as the “butterfly table” used for making prefabricated walls
When assembling a closed wall panel, once the frame and plasterboard has gone in it needs to be flipped for the insulation, wiring & plumbing to go in, which is where a butterfly table is used to flip the wall over. Then windows, doors, battens and external claddings can be added.
Randek’s international customers include the modular home builder BoKlok, a joint venture between Skanska and furniture retailer IKEA, and Katerra in the US market. In Australia, the country’s biggest prefab manufacturer, Timbertruss, is a customer, as well as a new prefab Passive House provider Eclipse Passive House.
In Australia, manufacturing closed wall panels in a factory and assembling them onsite still feels relatively innovative even though in Sweden this approach was in use in the 1940s and highly automated manufacturing in the 1980s. The panelised building approach means that once the foundation is ready, lock-up stage to be achieved in just a few days. A process that could otherwise take many months.
For Randek, one of the early movers in this space, this started off as small wall panelised systems before graduating to thicker and longer walls with more insulation and layers to reflect big leaps in building physics in the 1970s to reduce the energy use of housing.
Fast forward to today and the company has worked hard on creating building technologies that allow for “mass customisation” – where digital CAD-connected designs are put into an automated production line and a finished item produced. With each wall able to be completely unique.
Randek is a small company – around 100 employees – despite its prowess in developing technology that automates offsite building manufacture, creating the efficiencies that will see building manufacture refined and perfected much like cars and other complex products.
Australia’s troubled path to offsite construction
It’s no secret Australia has had a rocky introduction to the world of offsite construction.
Reints, who has been selling the building manufacturing machinery in Australia for around seven years, says that in some cases, the business case for prefab wasn’t as robust as it could have been. He says that some modular construction outfits were effectively doing a site build indoors and simply transporting it to the site, with no automation to create efficiencies that make investing in a factory worthwhile.
But as The Fifth Estate has discussed at length in the past, there’s several reasons the building and construction industry has been slow to innovate on this front, not least a lack of appetite to disrupt existing ways of doing things.
This is why a model that has only in a minor way altered the status quo has shown the most success, where builders place an order with a prefab manufacturer that will then make the componentry to be assembled onsite by the usual medley of contractors and subcontractors.
The other way that prefab works well, and is common in Europe, is fully integrated model where the builder designs and builds the house using prefab components like wall panels, and floor cassettes.
It will take mainstream uptake for prefab to accelerate in Australia
Reints expects the prefab industry to accelerate in Australia as the mainstream players pick it up. Until then, there’s less incentive for the broader industry to adopt it because the customer is absorbing the slow building times of normal construction methods and competitor companies are building in a similar timeframe.
“Once you start getting some mainstream builders that have a price and time advantage with panelised house building, and start to win work, that will put competitive pressure on other builders and the knowledge of the approach home buyers will grow.”
Reints says there’s can also be a misplaced fear that mass-produced buildings will all look the same. But with manufacturing technology that works off CAD designs, limitation on design is minimal.
He also says the preoccupation with unique builds misses what carefully-honed design & manufacturing leads to in terms quality control and cost, as seen in other industries.
And, builders can be left to interpret designs onsite as they go. Leading to potential delays and quality issues.
It also doesn’t help if architects want to make a one off build without paying attention to how the house goes together (on-site or in a factory). For offsite to succeed a knowledge of the processes in the factory and on-site is key.
“When it comes to a consumer actually choosing a builder, we see the preference for higher quality, and faster build times as an ongoing trend which favours offsite construction.”