1 Sep 2017

The power of prefab

From Nine To Noon, 9:21 am on 1 September 2017

It's predicted that by 2030 New Zealand will need 100,000 new homes - 70,000 of them in Auckland - to meet the demand for housing.

A prefabricated house being put together at Hobsonville Pt.

A prefabricated house being put together at Hobsonville Pt. Photo: Supplied / Fletcher Building

Would ramping up the construction of prefabs help address the accelerating housing shortage?

Prefab houses are 60 per cent quicker to build, cost 15 percent less, have fewer defects than traditional builds and are more sustainable, according to the industry body Prefab NZ, who for years has been pushing the benefits of off-site component manufacture.

Currently, 2 percent of complete buildings are fabricated, but in 10 years that is predicted to become 20 percent, chief executive Pamela Bell says.

Last week, Fletcher Living built a 170 square-metre house in just under 10 hours made largely of panels constructed off-site and assembled on a site at Auckland's Hobsonville Point.

So why has this method of construction, so prevalent elsewhere, remained so overlooked in New Zealand?

When it comes to building, New Zealand is "risk-averse", Bell says.

"We've been quite happy with the status quo. There's an aversion to risk and doing new things when actually we're making quite good profits the way we operate at the moment in the traditional building sector."

Prefab techniques are long-established in countries such as Sweden, Austria, Germany and Japan - and New Zealand has some catching up to do, she says.

"They've been going for 60 years. We're nearly there, what we are missing is a visible demand. There is a lot of potential for Housing New Zealand."

Compared with manufacturing, traditional house-building is very inefficient and off-site fabrication is more suited to the yacht building industry, she says.

"In Japan, one factory churns out as many houses as we build in an entire year, over 25,000. They will tell you also that no two are alike."

Prefabricated houses in Germany and Japan have a 30-year guarantee, while new builds in New Zealand have a one-year guarantee, she says.

Such long guarantees are possible because quality can be controlled in a factory in ways that are not possible on-site. A roof can made at floor level, for example.

"In New Zealand we go for the lowest cost [for building] up front. We need to look at all-of-life costs," she says.

Get the RNZ app

for easy access to all your favourite programmes

Subscribe to Nine To Noon

Podcast (MP3) Oggcast (Vorbis)