Addressing New Zealand’s housing problem
Most of us know two key issues facing housing in New Zealand are affordability and availability. Fortunately, modular homes, prefab buildings and pre-built homes are set to become part of the solution. With modular construction, the challenge is in meeting NZ’s seismic requirements. But the answer is finally here, with world's first Seismic Damage-Resistant System (SDRS) for multi-storey modular buildings. More on this in a moment. First, let’s take a look at NZ’s housing situation.
When considering affordability and availability, Auckland is the worst affected area, but it is also a problem in other regions. And some of the statistics in recent years have been alarming:
On average, 51% of a household’s disposable income is needed to service a mortgage
New Zealand has a house price-to-income ratio of 10 to 1, making NZ house prices amongst the most unaffordable in the world
The average Auckland house price is NZD$1 million
Contributing factors
Many factors affect NZ’s housing market in recent years. Some of the most prevalent include:
A small construction industry with construction skill shortages and resulting low productivity
Kiwi’s desire for bespoke home design and build
Highest ever level of immigration affecting housing demand
The Canterbury earthquakes and the Christchurch rebuild demand for construction skills and resources
Building up to meet demand
Once upon a time, Kiwis aspired to the New Zealand Dream of a family home on a quarter-acre section. However, for most Kiwis, this is no longer viable. High density housing is the key to solving New Zealand’s housing problem. Multi-story apartments are the norm in many countries and are urgently needed in New Zealand’s major cities, especially in Auckland.
The Auckland Unitary Plan is designed to help Auckland meet its economic and housing needs by determining what can be built and where, and by encouraging a higher quality, more compact Auckland, with more multi-story apartments.
Making modular housing part of the solution
Modular housing units are prefabricated off-site in a factory, then transported to the intended site. International research shows us that with modular building:
Construction speed is 30 – 50% faster
Construction cost can be reduced by 10 – 12%
Funding-related costs can be reduced by 35 – 40%
Thermal performance can be improved by 30%
Construction waste can be reduced by 50%
Impact on the local community is minimised
Multi-story modular building in New Zealand
Multi-story modular building uses factory-made volumetric units (modules). These are fitted-out and serviced building blocks that are stacked on top of one another to form a building. Such modules can be used for rooms, corridors, stairways, lifts and the roof of the building.
Seismic Requirements and Issues
However, in New Zealand, seismic vulnerability around modules is a concern. Seismic requirements of the NZ Building Code limit the use of modules to low-rise buildings only, such as houses, sheds, site offices and the ubiquitous prefab classroom.
A separate conventional Reinforced Concrete (RC) or steel support structure is often required in modular construction that is higher than low-rise. This results in limited use of modules in New Zealand, with increased construction costs and a longer build time. If only there was a solution. Well, now there is.
Introducing the Earthquake-Resilient Solution for Modular Construction
Dr John Jing has been instrumental in the development of the world's first Seismic Damage-Resistant System (SDRS) for multi-storey modular buildings. By allowing prefabricated modules with fitouts, services, insulation, enclosure and fire protection elements to be stacked up to 12 storeys high in New Zealand without any separate conventional RC or steel support structure this system means significant savings in both construction costs and build time. The good news? The SDRS will soon be used to create safer, more resilient and sustainable housing in New Zealand.