Prefab the answer to housing, report says
The prefabricated housing sector believes up to $40,000 can be shaved off the cost of building a new house if a co-ordinated approach is taken.
A new report by Prefab New Zealand and BRANZ shows prefabrication could shave $25,000 off standard construction costs and effective procurement of materials could remove another $15,000.
"Precision sub-assemblies" a form of prefabrication using modules and panels could remove $32,000 from the cost of a standard 157 square metre home, a cost saving of 15 per cent.
The report said New Zealand had an urgent need to step up its rate of new housing, but there were "serious doubts" the industry could meet demand with its present structure and traditional methods of construction.
Prefabrication not only saved costs but it saved time. Weather delays added 13 per cent to construction time, but off-site construction could reduce that, the report said.
Quicker building times meant lower financing costs, reducing construction time on a typical one-off small to medium building project by up to 60 per cent.
Industry productivity would also improve, by about 2.5 per cent.
The building industry struggles to improve its productivity because of the number of small players and boom-bust nature of the work.
The report stressed that while multiple building projects were the most cost-efficient way of using prefabrication, it did not mean houses had to be repetitive or standardised.
"Repetitive prefabricated elements may be modular bathrooms or prefinished wall panels," it said.
Labour housing spokesman Phil Twyford said his party's Kiwibuild plan to build 100,000 houses over 10 years was the perfect and possibly only way to bring in these methods.
"By building on this scale we can make possible the investment in plant and technology to allow offsite manufacturing," he said.
"We can grow companies who have the size and capability to move to a more manufactured style of building."
"The Germans and Scandinavians are doing it. It is time for New Zealand home construction to embrace prefabrication and offsite manufacturing in the way we build our houses."