Baugruppen & infra

The organisation responsible for the redevelopment of London’s Olympic park held a public consultation recently – specifically a consultation on a parcel allocated to residential development – so I went along. The offer was a fairly standard mix of private for sale and affordable (i.e. subsidised) housing; no baugruppen in sight. I had a couple of minutes with one of LLDC’s development professionals – at a senior level – and asked about baugruppen. They’re not being considered for any of the Olympic site, and the reason given was that a baugruppe would be making use of new infrastructure (i.e. roads, piped services) while not paying for it. In essence, a free-rider argument. Justifiable? I don’t think so, not without more detail. There are lots of implicit transfers going on in any kind of urban development and quite often private for-profit development benefits without paying. For example, the Docklands Light Railway was upgraded at taxpayer expense in advance of the Olympics. It now serves Westfield Stratford, a major new mall. It’s true that Westfield’s developers paid for some local transport upgrades, but not – as far as I know – any part of the DLR. But perhaps this sort of accounting is always going to be imprecise. Some transfers a city planner will simply allow, with a shrug. For example, the homeowners now living near the location of the planned Northern Line extension into Battersea are likely to benefit from that piece of infrastructure, but no one is going to impose some special tax on them.

My hunch is that the LLDC simply prefers to work with big players; organisations that can be leaned on for some sort of contribution towards something. In that context, would-be baugruppen are just irritating small fry. They could be tolerated – or even welcomed – but no luck this time.

Anyway, the model looks good:



Berlin baugruppe projects compared

Dessau graduate student Winnie yuen-pik Chan has done a comparative study of Berlin baugruppe projects:

The comparison between a private developer project and a baugruppe project on pp. 61-64 is interesting. This is a German private development, so decently large. The baugruppe advantage here is cost.

Danish density

Following the last post, I thought I should try to get some data on housing density in Copenhagen, which is widely taken as a model for urban development. From this paper by Jin Xue at Aalborg, I get a figure for habitable space in Copenhagen of 51 m2 per person. Interestingly, this is at a population density of 27.7 pers. / ha, which is relatively low. There’s further interesting commentary on Copenhagen’s housing model by Greg Bamford, Queensland, who supports the Danish approach, emphasising building separation and generous provision of usable semi-private / shared outdoor space.

British density

Britain is often described as crowded. London? Well, it seems stupid even to ask the question: of course it’s crowded. But I’d like to flip the question around. How much space can a person in Britain reasonably expect? And, for comparison, how much space does he or she actually have?

Some back of the envelope arithmetic. The UK has a land area of 243,610 km2. The population is 62.5M or so. That gives 3,900 m2 per person, or 0.39 ha. A decent amount. Of course, most people live in urbanised areas; let’s concede that this is desirable for economic reasons. So, how much space can a person living in a British town or city reasonably expect?

Leeds, my home town, has an area of 562 km2 and its population is around 750,000 (source). That gives 749 m2 per person (0.075 ha). But two thirds of this area is designated as green belt (ibid.). For now, let’s accept this planning designation: it curtails the area per person to 250 m2. That’s land area. Of course, we have the technology to build multi-storey structures on the land, potentially increasing the area per person. So there’s a multiplier: the plot ratio. Let’s assume, conservatively, that Leeds can be developed to a plot ratio of 2. This ratio can be taken to allow for open space such as roads and private gardens, and hence a typical structure might be 3-4 storeys. Sounds like a reasonable development goal? OK, then. A plot ratio of 2 gives us 500 m2 per person.

Now, how much area does a person living in Leeds actually have to swing a cat? This is a hard question to answer with elegance or precision, but here goes. Around half of the dwellings in Leeds are classified as having three bedrooms; this is the most common dwelling type (source). Take this as representative. The median gross internal area, for a three bedroom house in the UK, across all tenure types, is 92 m2 (source). If you take it that a three bedroom house in Leeds is lived in by three people (this might be conservative), then around 30 m2 per person looks plausible. So what happened to the other 470 m2? Is it all given over to employment use? Railway lines? Schools? Hospitals? Parks? Is it just wasted? Reserved for grouse shooting? It’s possible I’ve gotten my sums wrong, but I have to say I find this difference – between the space people could have and the space they actually have – just flat out boggling. Call it naivety if you like.

Coincidentally, when the LSE Cities project looked in detail at the Green Street East district of Newham, London, they found 27.8 m2 of habitable space per person, comparable to my (very rough) estimate of living space in Leeds (source). In the same study, the LSE project also looked at the Town district of Hammersmith and Fulham and found 49 m2 per person. However – and this is the interesting part – when measured in terms of persons per hectare, both districts had very similar densities: 176 pers. / ha in Green Street East versus 153 pers. / ha in Town. So in Town, Hammersmith & Fulham, for a given land area, more area is available to people. It’s also the wealthier district of the two. Conceivably, the provision of this extra space in Town is explained by a higher plot ratio, although not necessarily: the only firm conclusion I can draw is that this part of Hammersmith & Fulham just does better at land utilisation. Less land is wasted: more is converted – perhaps by building higher – to habitation. Which is what we want, right?

Update: On re-reading this, it occurs to me that a problem with the topic might be equivocation over the term ‘density’. Building taller increases built form density but doesn’t have to result in higher population density (and perhaps shouldn’t). A lot of UK discussion focusses on population density while glossing over the issue of habitable space. For example, Ed Glaeser:

We maximise our damage when we insist on living surrounded by greensward. Lower densities inevitably mean more travel, and that requires energy. While larger living spaces certainly do have their advantages, large suburban homes also consume much more energy. Anyone who believes that global warming is a real danger should see dense urban living as part of the solution.

This misses something important. Energy-intensive ‘sprawl’ is bad, yes, but people like living space; we should somehow try to arrange things so that they can have more of it.

UK self-build pioneers

Oliver Wainwright describes two group self-build schemes; one in Lancaster, another just outside Leeds. These two projects both emphasise building a sense of community, and have design features – such as a communal kitchen in Lancaster – to reinforce that. This might be a step too far for some, so it’s worth bearing in mind that you don’t have to sign up for everything good and holy just because you’re building as part of a baugruppe.