Greater Ōtautahi supports minor amendment to District Plan to enable perimeter housing

Greater Ōtautahi has a plan to unlock perimeter housing in Christchurch. By making one tiny amendment to the district plan, we can enable housing density to be done better.

Spokesperson Jack Gibbons says: “We’re relatively happy with the proposed District Plan as it stands, as it will encourage more housing within Christchurch. We’re glad the National government, and especially Minister Chris Bishop, has continued to push for housing affordability in New Zealand. However, we think by making a small amendment to the height limits, we can enable housing density done better.”

Perimeter block housing builds high at the front of the property, creating a shared outdoor space.

Perimeter block housing refers to situating buildings at the front of a site, and building to the full height allowed, usually up to six  storeys. This leaves a large shared yard at the back of the site. As the city grows and each plot on the block is redeveloped in this style, a large green space is then created in the middle.

As Jack says: “The perimeter blocks in Barcelona are probably the most well known example of this done well, but they’re pretty common all over Europe. In the large capitals, but also in Christchurch-sized secondary cities like Brno, Czechia.”

“I was travelling around Europe this year, and seeing how much better their cities are when it came to housing and getting around, I understood why so many of my friends have left to come here. But it also left me wondering - why are so many back home afraid of multi-storey housing?”

The benefits of perimeter housing are numerous - sunlight access is plentiful, green space is maximised, and the balance of privacy and street visibility can be managed. This allows for safer streets, and the shared communal space within the block helps build communities, something sorely lacking with the current status quo.

New Zealand is still in a housing crisis, with some of the highest ratios of income to house prices in the world. Christchurch, while fairing slightly better than Wellington and Auckland, is not immune to these issues. With thousands of people, mostly younger, leaving for Australia and Europe, it is essential we bring the cost of housing down and give them a reason to stay.

The typical infill housing development built today is a series of two or three-story townhouses, with window outlooks facing neighbours. These have become known as “sausage flats”. This natural infill has been going on since the 1960s.

This pattern is infinitely better than building nothing; they do provide a lot of housing in places people want to live. But there are some suboptimal urban design outcomes - privacy implications for neighbours, everyone gets a small yard (that you can’t do much with), and high lot coverage means trees and nature are replaced by concrete car parks. 

This isn’t necessarily developers choosing such outcomes,  it is mandated by our planning rules. Mainly by requiring height in relation to boundary controls - with buildings having to be a certain distance away from the boundaries at different heights.

The proposed district plan is closer to enabling perimeter housing than in the past, but unfortunately it adds quite restrictive height in relation to boundary controls. For example, within the ‘Four Avenues’, parts of a building higher than 14 metres have to be set back between six and eight metres from both side boundaries. This effectively caps buildings at just four stories when plots are narrow, as they almost always are in older central parts of the city, because there is simply not enough building width left to have any usable space above 14 metres.

But it gets even worse! In New Zealand, when buildings go over three stories, a raft of additional regulations are triggered, i.e., fire safety, structural engineering, and lifts. This means four-story residential buildings have much higher build costs per square metre, and so the de facto cap on building height will likely remain at just three stories.

The fifth, sixth, and onwards stories are cheaper because everything is already in place, it just has to be extended. This means a six-story building has a lower cost per square metre than a four-story building - enabling more housing supply, at a lower cost.

For these reasons, we believe that buildings of at least six stories must be enabled on these common, narrow, high-density-zoned plots within the four aves in order to break out of the awkward “sausage flat” topology.

The solution

By changing one line in the district plan document - amending 14 metres to 18 metres in section 14.6.2.2.c.iv. of the proposed district plan, we can enable practical  perimeter block housing. There was substantial evidence in favour of perimeter housing supplied to the IHP during the hearings process.

Media contact: Jack Gibbons, greaterotautahi@gmail.com, 021 546 545