So-called 'hidden homes' could be a fast, low-impact solution to New Zealand's housing crisis, according to new research.
At least 180,000 extra homes could be created either by partitioning existing residential properties or adding extra units on to existing sections, the report found.
In Auckland alone, 45,000 properties are suitable for partitioning, report says Photo: 123RF
The report – by the Centre for Research Evaluation and Social Assessment (CRESA) – was carried out as part of one of the government's National Science Challenges.
Discussion of the housing crisis has largely focused on the constraints on mortgage finance and arguments over land supply and land prices, but there is an under-utilised housing resource right under our noses, CRESA's director Kay Saville-Smith says.
The report estimates 12 percent of NZ's housing stock – up to 45,000 homes in the Auckland region alone – could be partitioned.
It also found complicated and inconsistent council rules mean too few additional dwelling units (ADUs) are being put on spare land.
“There was a mushrooming of granny flats in the 1970s, but times have changed. It’s probably Granny that’s got the house now!
“The reality is there are a lot of older people with space to spare that could have a proper unit put on.”
The idea of partitioning homes has fallen away in recent decades, Saville-Smith says.
“This is not new in New Zealand. If you think about all those great big houses that were built in the 1880s through the ‘20s, ‘30s, ‘40s and again in the ‘50s and ‘60s there was a lot of partitioning in those great big villas.”
Many four-bedroom homes today are eminently dividable and building techniques such as kitchen pods make this a relatively easy thing to do.
Empty-nesters might find this a particularly attractive option, she says.
“It gives those that need to downsize the opportunity to partition their home without leaving the community.”
The advantage of an ADU is that land needn’t be subdivided and new ADUs, when prefabricated, can be developed quickly.
But people aren't clear on what's allowed as every council has different rules or no rules at all governing ADUs, Saville-Smith says.
“If you go to one council the ADU might be allowed to be 35 square meters, another it might be 80 square metres and it might vary within a council area according to zone.
“Some councils even specify who can live in an ADU. You can have an ADU but it can only be a family member. There’s all sorts of variety of stuff going on and there’s no logic to it, no coherence, no reason for it. It’s just rollovers from old planning decisions of 50 years past.”
National leadership is needed to get councils all on one page, she says.
“We need a national policy around ADUs and a national policy around portioning and that needs to be led by central government and it means all the councils need to come together.”
Housing minister Phil Twyford has a copy of the report, Saville-Smith says.
