This is a guest post from Brendon Harre in Christchurch. It addresses an issue that’s near and dear to Transportblog: How do we better enable positive change in the built environment?
Solving the housing crisis in New Zealand will require many reforms and much effort. Some of the needed reforms will face opposition and will be difficult to implement. There will be tension between the national concern about improving housing supply versus some local interests in retaining the status quo.
I want to focus on one particular easy to implement policy option, which I think could successfully navigate this political dynamic. The essence of the proposed reform is to establish a nationwide intensification right for situations where neighbours agree. A right to reciprocal intensification will create a new urbanist tool for New Zealand, allowing a better housing intensification supply response, so that people can build in parts of our towns and cities where people want to live.
The first step would be to agree as a country on a height limit that all property owners could construct up to as a right. I would suggest three stories would be reasonable, as this is a similar scale to natural features like trees.
Local areas through zoning provisions would still retain existing setback and shade planes rules that determine how far buildings must be constructed from site boundaries. For instance, a shade plane is an angle going inwards, which building height and bulk cannot exceed. It is taken from a certain height directly above the section boundary -2.5 metres in the below diagram. These rules also limit the size of buildings – and hence reduce the number of dwellings that can be built on a given site.
The second step, which is the main thrust of my proposal, is that New Zealand should adopt a system where neighbours can reciprocally agree to drop the shade plane and set back restrictions along their common border. This reciprocal intensification right could be implemented as a national policy statement under the RMA, which local authorities would then be obligated to implement. So in the above diagrams, if there was a section to the north or south and if the two property owners agree, then they would both have the right to build up to their adjoining boundary – utilising the appropriate building code for firewalls etc. If other adjoining neighbours disagreed, then on those boundaries the standard setback and shade plane rules would apply.
Of course there would be many property owners who wouldn’t want their neighbour to build right up to their boundary. But some would see the advantage in co-operating, so they have the option of adding a granny flat or redeveloping their entire site. Making this reciprocal intensification right a choice eliminates the major criticism of up-zoning. Being, up-zoning dictates an exchange of a neighbour’s access to sun, views and privacy for the opportunity to intensify. Some property owners believe they will be worse off if this exchange is codified into the zoning map.
If reciprocal intensification rights were spread across a large enough area, then this would give the opportunity for a lot of intensification – in the form of duplexes if two neighbours agree and European style terrace housing if many neighbours agree. There are 1.8M private dwellings in New Zealand – if just 1% of those properties were intensified from one dwelling to three per site over, say, ten years, that would net an additional 36,000 new homes. I am not sure if 1% and one house intensifying into three are reasonable expectations, but it shows that even with modest assumptions this proposed policy reform could have an impact on the housing market.
The main benefits of a right to reciprocal intensification are:
- It decreases transaction costs for site assembly. The national policy statement would mean no resource consent or property purchase would be required to develop sites more comprehensively. Currently to achieve site assembly, either neighbours would have to go through a complex and uncertain RMA process or a property developer would need to buy up the neighbouring sections.
- It encourages a more desirable urban form as it gives property owners the ability to build across their property frontage so that new housing faces the street. Currently our zoning rules encourage infill housing that goes down the length of the property.
- It gives greater housing supply options for building types with construction costs per square metre comparable to standalone housing. Small apartment buildings tend to be cheaper to build compared to high rise apartments because they can be built as 3-story walk-up units. There is no need for an expensive concrete elevator core, mechanical ventilation, sprinkler systems, underground parking and expensive structural engineering.
- It allows housing supply to respond to locational demand.
- It allows housing supply to respond to housing size demand. There is evidence of an under supply of 1–2 bedroom homes in the property market: The largest increase in household groups are singles and couples, yet very few one or two bedroom homes are being built.
I believe reciprocal intensification will be driven by both supply – in terms of its ability to lower the cost of infill and redevelopment – and demand. Demand will come from urban areas with high amenities – like proximity to employment, easy public and private transport access, markets/shops, entertainment and desirable natural environments like beaches, parks and forest.
In Auckland not all high amenity areas have been up-zoned by the new Unitary Plan. So for the city most suffering from New Zealand’s housing crisis there is an opportunity for reciprocal property right supply to increase housing supply in places where there is a demand for it. Density maps of Auckland indicate that outside of the city centre there is a sudden drop-off to a flat density gradient, unlike similar sized and geographically constrained cities –such as Stockholm. Economic theory indicates density should gradually decline with what is labelled the ‘missing middle’ housing.
Reciprocal intensification rights will not by itself be enough to enable all of the development we need. Other intensification restrictions such as minimum section sizes, minimum car parking requirements, site coverage rules, viewing shaft restrictions, heritage restrictions, secondary kitchens, etc may be as or more significant in the way they restrict the supply of housing intensification options and should also be reviewed by affordable housing policy makers.
However, I think reciprocal intensification rights would be a less controversial first step to intensification compared to widespread up-zoning, which results in some property owners who oppose intensification to fight such measures. These local interest groups which may only represent a minority of locals obstruct reasonable efforts to address restrictions on housing supply.
I believe New Zealand should give greater weighting to the national concern about affordable housing supply compared to the minority local interest in retaining the status quo. It has been my goal with this reciprocal intensification proposal to create a fair and appropriate first step to address this imbalance.
- This article was based on an article for Interest.co.nz titled Brendon Harre and David Lupton set out the case for more, and more variety of intensive housing options in New Zealand’s urban areas and a longer version of the article which also discussed the possibility of larger co-operative neighbourhood schemes.
- There are some architectural slides from a US city that transformed traditional standalone housing suburbs into suburbs of duplexes and terraces by reducing allowable section sizes to a little over 100sqm and by not having side yard setback and shade plane restrictions. The end result is quite pleasing.
- There is an article and podcast of an academic economic discussion of the wider costs to the economy that unaffordable housing imposes, how the various restrictions on house building contribute to this and some possible remedies, H/T Facebook group Market Urbanism.