Unitary Plan – Is there a devil in the detail?

This is a guest post from Andre de Graaf who is a principal at Construkt

We are all still slowly digesting the ramifications of the Draft Unitary Plan and I suspect it will be a while yet before further scenario testing and some prudent ground “truthing” moulds the Plan into a mechanism that will allow the aspirations of the Auckland Plan to be executed in any real sense. The essence of the Unitary Plan is certainly to be applauded. The creation of a more compact city is paramount for many reasons.
But like with many things, I think there are parts of the Unitary Plan where the overwhelming tendency is to simply offer up that, which already has tried and tested patterns established. To support this so called line-of-least-resistance, we are inadvertently ensuring that portions of the planning frameworks do not stray too far from the past. Perhaps it’s also a case of – if it ain’t broke don’t fix it.
While there is always a good argument to be made for that, I can’t also help but think, ok so it works, but could it work better!

Although the draft Unitary Plan is a great step in the right direction, I do have some concerns about the detail (specifically some development controls) that I believe will frustrate good compact urban form.

Given my involvement both at masterplan[1] level and with some of the housing designs[2] , I thought it useful to reference the mostly completed (stage 1) housing at Hobsonville Point to demonstrate my thoughts. However rather than simply offering an overview of the actual designs, I want to focus on some alternate thinking in respect of the development controls that guide the urban form and have a substantial effect on the streetscape and density of our neighbourhoods.

Fig 1: View of stand-alone houses along Station Street, Buckley Precinct, Hobsonville Point.

Fig 2: View of stand-alone houses facing laneway (off station Street), Buckley Precinct, Hobsonville Point

Figures 1 and 2 show stand-alone houses already completed within the first stage of the Buckley Precinct. These have proven to be very popular and whilst I do not necessarily advocate these to be a perfect example of housing to be rolled out across the wider Auckland – in fact there are always lessons to be learned – the feedback has been very positive and they have sold very well.

At this point it is worth noting that the development controls developed for the Buckley Precinct (as part of the masterplan) include neither a Minimum Lot Size nor HIRB control.
It is these two particular development controls, so ubiquitous in all our planning documents I wish to discuss.

Minimum Lot size:

Whilst this varies depending on current zoning provisions across Auckland, and whilst this makes sense in certain character areas, one has to question why this provision should be there at all for other zones that anticipate intensification – perhaps it comes down to how one defines medium density as this appears to be a relative term. The following are site size requirements for current and proposed zones that contemplate medium density housing:

Operative District Plan – Residential 6A zone, stipulates 375m² as a minimum lot area.

Draft Unitary Plan, this density appears to be captured by the Residential – Mixed Housing zone, which imposes a minimum site size of 300m² (unless total site area is 1200m² or greater in which case no minimum applies).

Fig 3 below is a snap shot of the first stage housing that was constructed at Hobsonville Point. I have shown in red the lot area for some of the sites that we have designed the houses. As you can see most of these sites are below 300m² and in some cases well below.

Fig 3: A portion of the Buckley Precinct already constructed at Hobsonville Point

Escalating house prices seem to have many reasons in Auckland (too complex to go into here), however a large component of a ‘house and land package’ is the value of the land. For this reason the land component to house type should be keenly interrogated such that – what I call “slop” land – is eliminated or at the very least reduced to a minimum. Within the Auckland isthmus a single section is now likely to sell[3] for approximately $750.00 per m².

The example above of stand-alone house sections on lots of say 275m² (vs the current minimum of 375m²) gives an area difference of around 100m² – producing a cost difference of around $75 000.00 for the land alone. Of course under the Draft Unitary Plan, with a minimum lot size of 300m², that difference reduces to $18,750. But 18k…. is… well 18k, and for many families possibly the difference that determines where and how they live.
In my view we should also consider terraced houses as single or individual sites as they do in countries like The Netherlands, but this is worthy of a separate discussion that I will not progress here.

Increased housing choice and a shift in expectations on the ability for households to pay are backed up by sales evidence that smaller homes are proving very popular at developments like Hobsonville Point .
With a shift in housing choice, and affordability a real issue, one has to wonder why setting minimum lot sizes (for a zone clearly anticipating intensification), is sensible at all?  In answering that question we of course need to consider the intention of minimum lot sizes and why they are imposed in the first place, but I will come back to that later [5].

Height in Relation to Boundary (HIRB):

Below is an extract of this development control contained in the Draft Unitary Plan (only slightly different from the current Operative Plan that has the boundary height at 2m).

Fig 4: HIRB diagram – example from draft Unitary Plan

The purpose of this control is stated as;

Manage the bulk and scale of buildings at boundaries to provide sunlight access to neighbouring properties and provide space between buildings.

Now, while such controls are well intentioned to preserve these amenities, the reality is that section sizes historically have been larger and these controls have allowed sufficient design “wriggle” room to create our desired suburban form and landscape. However in the last decade or so with the progression to more tightly spaced, yet increasingly larger dwellings [6], we have ended up with some very poor outcomes. In my view this particular control has simply not adapted.

An example of this is depicted below – redolent of many areas around Auckland housing built in the last decade or so.  Ignoring architectural merits, what I see more than anything else here, are houses as “slaves” of the HIRB control, all the more so as lot and house sizes have inversely grown.

Fig 5: HIRB as typically denoted by red lines.

Below is an example of stand-alone housing at Hobsonville, where the development controls for this precinct do not impose HIRB.  A clearly defined street edge becomes possible.

Fig 6: Note – Windows to side boundary are secondary windows. The primary window faces the street boundary.

Of course the other housing form that was exempt from the HIRB (as they pre-date), are around the older parts of Auckland.  A typical example is shown in Fig 7 below.

Fig 7: An example of housing from the older parts of Auckland.

So coming back to the intention of minimum lot size and the purpose of HIRB – sunlight and space between buildings, I have contemplated some alternatives that nevertheless seek to protect the same amenity values.

If we take a ‘let-the-design-dictate’ approach we might consider setting distances from boundaries relative to the rooms or spaces that they relate. For example the distance from a living space to an adjacent boundary would be much greater than say from a garage or bathroom. This is actually a concept covered in the Moreland Higher Density Design Code, specifically the section dealing with Building Separation of which I have extracted the relevant page below:

Fig 8: Building separation guidance from Moreland Higher Density Design Code.

Of course the context is very different, but I did find the very notion of outlook as a separation control intriguing.

We interpreted this for the Hobsonville Point project and developed this idea with Council. Essentially it is a building spacing or separation based on outlook rather than a generic default boundary control. By way of example the following scenario was proposed:

Primary Outlook: This relates to living spaces (lounge, living, dining) and requires a min 6m setback from Lot boundary

Secondary Outlook: This relates to private spaces (bedroom, study) and requires a min 3m setback from Lot boundary

No Outlook: This relates to service spaces (garage, laundry, passages, bathroom) and allows a min zero setback from Lot boundary

Note: These are to lot boundaries – so it is the cumulative total of two outlook types on either side of the lot boundary that will determine overall building separation.
If a room has more than one external wall you simply nominate the wall that is subject to the outlook setback requirement.

We have tested many different scenarios with actual house designs to see how this would unfold and I have included one example as Fig 9 below – lot no. 2 being the subject site.

Fig 9: Scenario testing diagram.

Essentially the outlook setback attempts to give the designer greater freedom, to place and manipulate, the house form and space allocation to best suit the site conditions, orientation and context (including neighbouring properties).

Now what I have not yet mentioned is that additionally there is an overall height limit and importantly that there are specific requirements to ensure solar access to the private open space (POS) is achieved.  This can easily be demonstrated by way of shadow analysis along the lines of the example diagram in Fig 10 below:

Fig 10: Example of shadow analysis diagram.

Note: Whilst unit 2 is in this case the subject site, all neighbouring properties (either as existing or as proposed) must be included to demonstrate that they either retain solar access to their POS or for a vacant site that the POS for a proposed house can be located in a way that meets all the development controls.

Note: The minimum solar access requirements are defined in terms of min number of hours (in this case 3) at set times of the year when at least 50% of the POS must receive sunlight.

I assume that for some designers demonstrating shadow analysis can be somewhat intimidating and or technical, but if a clear and simple methodology is established, that all designers can easily follow, it is actually quite straightforward. In my view shading diagrams (particularly as urban form intensifies) should form part of any basic analysis in arriving at a preferred design.
How Council vet or test an applicant’s proposal for accuracy would of course also need to be considered.

One last thing I will touch on is the issue of privacy and overlooking, as this is invariably raised when attempting to work with medium density environments.

In terms of physical separation the outlook setback control would deal with this in the same way that say; yard setbacks, HIRB or minimum lot sizes would have influenced building separation.
Design (again particularly as urban form intensifies) should always contemplate the issues of privacy and overlooking at the outset, and just as shading analysis, should be a basic up-front consideration long before secondary yet simple mechanisms such as screens and planting, assist in maintaining privacy.

I do think we sometimes have an unhealthy obsession for privacy. As long as people have privacy when they choose it and can adjust their environment to invite neighbourly interaction when they do seek it – is in that, not the real value and health of communities?
As Jane Jacobs in her seminal work, The Death and Life of Great American Cities, observes;

“Architectural and planning literature deals with privacy in terms of windows, overlooks, sight lines. The idea is that if no one from outside can peek into where you live – behold, privacy. This is simple-minded. Window privacy is the easiest commodity in the world to get. You just pull down the shades or adjust the blinds. The privacy of keeping one’s personal affairs to those selected to know them, and the privacy of having reasonable control over who shall make inroads on your time and when, are rare commodities in most of this world, however, and they have nothing to do with the orientation of windows.”

Summing Up:

We live in an ever-changing world with ever-changing life styles. We need to ask ourselves if some current development controls have kept pace and are they the best we can do in enabling innovative design without necessarily precluding a more traditional approach. I am not talking about architectural merits here but more about the placement, size and footprint of houses. I would argue that the notion of minimum lot size is premised on the site coming first and a house design that follows. This is true for the past several decades, but the fact is many new land developments in Auckland (both brownfield and greenfield) has moved on and a masterplan focus is brought to bear that clearly contemplates a particular urban form long before lot size and its shape factor is settled on.

The question is when more often than not the house comes first and the lot is sized around it to preserve certain amenity and outlook – is a min lot size the best way to achieve this? And if the site (say infill) comes first and the house design follows does an outlook setback control still hold?

Additionally – if space between buildings can be more responsive to the actual house design through an outlook setback control, whilst preserving solar access to Private Open Space – do we need a HIRB control at all?

We can play around with development controls, and it is important that we do to ensure good outcomes, but in the end the real test must be that of quality and beauty. Nick Boles [7] a planning minister in the UK makes the point:

“In a nutshell because we don’t build beautifully, people don’t let us build much. And because we don’t build much we can’t afford to build beautifully.”

Hobsonville Point has its own design guide and a design review panel. Every house design is subject to the design review panel process. Good design and quality, no matter what the urban form, must be at the core of everything we do if we truly want to make Auckland the world’s most liveable city.

[1] Both in association and in a joint venture with Isthmus Group, providing urban design services to Hobsonville Land Company (HLC).
[2] Under a separate engagement with Universal Homes, one of several builder partners involved with the construction of housing at Hobsonville Point.
[3] Depending where in Auckland you are this would be higher or lower – I have simply averaged this for the purposes of this discussion.
[4] Chapter 11 (Priority 2) of the Auckland Plan gives a good overview of the shifting demographics and household make-up.
[5] See first two paragraphs under: Summing Up.
[6] See Auckland Plan, Chapter 11 – Priority 2, Increase Housing Choice to Meet Diverse Preferences and Needs.
[7] See the Spring issue 2013 of Urban Design Group Journal – 126 (Page 34, A manifesto on 21st Century suburbs).

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