Urban Form: Ponsonby and Takapuna

One of the most damaging features of the Draft Unitary Plan is its proposal that it should be possible to subdivide existing residential lots down to 300 square metres. The main reason given is to allow developers or land-owners the ability to provide for an affordable home on their title. But the controls in place to ensure that the second unit, or minor unit, or secondary dwelling will be in keeping with the neighbourhood are very limited.....

This map shows about how much of Auckland was urbanised by 1915. The green line shown is today's (or yesterday's) Metropolitan Urban Limit.

This aerial is of a section of old Ponsonby. Sometimes known as "the worker's cottages". Now part of Auckland City's heritage....

This is a typical street view. Narrow streets. Limited on street parking. Low fence lines. Great family neighbourhood. Close to shops and schools and CBD and frequent bus services. Interestingly - you can see a two story home - built to replace one of the old cottages....

Built in the time of tram public transport, and very few cars.

Now let's do a bit of analysis of how the land is actually used. I've gone in closer here. You can still see that 2 storey place - built on a diagonal (so contrary those Ponsonby types) - across the street from the parked red car. I look at the space taken up by 10 houses - pretty much chosen at random...

The Council GIS system allows you to measure the land taken up by these 10 residential lots. So, for 10 homes, land required is 3,819 square metres....

The footprint of the 10 homes on those 10 residential lots can also be measured. They add up to 1,265 sq metres.

This table shows the simple calculation of the average lot and home footprint size in the sample area of 10 homes. About a third of the lots is taken up by the home, and the rest is garden or driveway etc. The key thing here is that the average roof area is 126 square metres (which means the average floor area is a bit smaller - allowing for the width of gutters). And the average lot area is 380 square metres.

Jumping forward in time, this map shows how much of Auckland was taken up by urban development by 1975.

This aerial shows a section of "old" Takapuna. It would have been planned and developed under the jurisdiction of the old Takapuna Borough Council. The streets shown here include sections of Jutland and Norman Roads.

Here is the streetview. Typical of the land use in the area. Much wider street than in Ponsonby. Built in the era of the motorcar. Very little public transport. Everyone had a car. Could park it off the street....

Doing the same exercise as with Ponsonby, I have chosen an area with 13 typical properties. You can see here the total area for the 13 original residential properties - as subdivided when the area was first developed.  

This image shows the original homes that were built on the 13 original lots, and calculates the footprint area of those homes... I will come to the other buildings a bit further down this posting...

This table shows the calculation of average lot size and house area for the 13 lots. If you compare with Ponsonby, you will see that these Takapuna residential homes are on average almost twice the size of the Ponsonby cottages, and that the lots they are built on are almost 3x the size of the Ponsonby lots.

The new North Shore City Council was established around 1989 (after amalgamation). And then in 1991 the Resource Management Act became law, and NSCC adopted a new District Plan. This enabled complying minor units to be built on sections that were big enough, and also enabled lots to be subdivided down to 450 square metres. This marked the beginning of the age of Takapuna infill. The purple shaded buildings shown in this image, have been built since the new plan enabled them.

So, based on this small sample, 7 new home units were built on these 13 lots. Two of the lots have been formally subdivided. Thus most of the minor units are still incorporated into one single land title. It would be fair to say that the low hanging fruit offered by minor units for affordable housing in Takapuna has been plucked. Whether these are used as granny flats, or for older children, or students living at home, or members of the family who can't afford anywhere else to live - is unknown.

The Ministry of Business, Innovation and Employment has recently prepared a very useful assessment of what land there is in Auckland for affordable housing. This slide is drawn from it. In summary it declares that "Infill has a more limited dwelling capacity than redevelopment" - and defines redevelopment is what happens when you demolish and start again.

For a variety of reasons infill is a problematic way to solve the problem of affordable housing supply. Much of the minor unit accommodation that has infilled residential property on the North Shore is already in place, and has replaced trees and outdoor space, and in many cases provided homes that are not of a high standard in terms of insulation, energy efficiency and other aspects of household amenity.

The Unitary Plan provisions which drop the 450 square metre limit down to 300 square metres will likely unleash another round of slap-dash minor unit construction and slum-lords. It is a short-term short-cut. What Auckland needs now is a more concerted look at urban areas that are crying out for redevelopment, rather than the ad hoc piecemeal approach of infill.