Monthly Archives: September 2015

Building in the green belt: 1

This is a post in two parts. In this first part, I’ll set out some reasons for considering green belt development. In the second part, which will follow (eventually), I’ll describe a test case proposal for a specific green belt site.


People have made good arguments for developing some of London’s green belt as housing. After thinking about this for a bit, I agree. The quantity of land designated as green belt is excessive, given the intense pressure on London’s existing housing and the escalation of house prices. Green belt designation helps to create that pressure and the rise in prices: it is inequitable policy.

I’m not arguing for the abolition of green belt: I think it should be reformed. Not all green belt land is of equal quality. This helps enormously when it comes to considering how some of it could be converted to housing. We are not talking about national parks, or anything much resembling ’nature’. Instead, large tracts of green belt are used as monocultural farmland (leading to the argument that suburban housing, with extensive hedge planting and gardens, delivers better biodiversity). Big chunks are laid out as golf courses. Some green belt is not even green, and of non-existent amenity value: gravel pits, surface car parking.

Still, there are people who believe that the green belt shouldn’t be touched. What are their arguments?

1: Limiting the city

One argument for retaining the green belt is that limiting the city is good in itself: why should the city be allowed to grow indefinitely? This connects with arguments about immigration: why should the population grow indefinitely? Here I think we run into a kind of fallacy where principle is argued against degree. Most would accept that at some point a city, or a region, or a nation, is ‘full’ and should not grow further. The issue is whether or not we’re at that point. I don’t think London is ‘full’. I also don’t think that the very high densities typically now proposed for urban sites are acceptable, or that existing lower density areas can be made denser to a sufficient degree (I will discuss this further below). Therefore, to allow for growth, the green belt constraint on the city should be relaxed. Exactly how far is a matter for further argument, but it’s an argument in which all sides can accept the principle that there should be a limit to growth. Advocates of green belt development are not saying that the city should grow forever, until everything is ‘covered in concrete’. Instead they tend to agree, as I do, that there should be a green belt; just not the green belt that we have.

2: Non-green belt solutions

Another argument accepts that the green belt contributes to the pressure on housing but claims that this pressure can be relieved in other ways. Development of the green belt is therefore unnecessary, at least for now. This is a much better argument. But let’s look at how urban intensification is currently done.

Open market sites

The key fact here is that suitable open market urban sites in London are scarce and expensive. This has led to a very large increase in density in those places where development is happening. The London Plan calls for a maximum residential density, for sites with the best access to public transport, of 1,100 habitable rooms per hectare. A typical modern housing development will tend to exceed this density by a large factor (2,000-3,000 habitable rooms per hectare is not uncommon). This has two consequences. One is height: London is rapidly acquiring towers, or high slab blocks. These are relatively expensive to build and carry significant environmental penalties: poor daylight, wind at street level, and visual impact on the skyline. Another is intense pressure on the amenities that go with housing: child play space, car parking, schools. Partly as a result, developers have aimed this style of development at people without families: that is, occupants who can accept relatively small dwellings, don’t need cars, and don’t call on facilities such as schools or parks.

Non-traditional urban sites

In response to tower proliferation some people have called for moderated density, albeit still an increase, and have looked for alternative urban sites across which non-high rise housing might be distributed. A recent competition organised by New London Architecture threw up a range of ideas. In addition to (the usual?) capsules and houseboats we saw residential schemes that in effect double count land: housing on top of retail car parks, on top of schools and hospitals, on top of railway lines, and in one perverse proposal, instead of roads (refuse collection and fire brigade access to be determined). But the thing to note here is that the principle of mixed use development already informs planning policy in every London borough and has not significantly moderated the cost of land or reduced pressure on housing. Stacking uses is hard. The 2005 Gerrard’s Cross tunnel collapse shows the risk of building over a working railway line. It is almost impossible to imagine building on a working hospital, or even on top of a school. How do you connect services? How do you guarantee un-interruption of existing services? (Hospitals are very highly serviced.) How do you even get to your front door? (Hospitals are secure buildings, and schools require secure sites.) Housing on top of shops is feasible if starting from scratch: this was first seen on a large scale in the 1990s with the development of the Cromwell Road Tesco, and is a feature of the recent Woolwich Central development (and perhaps undeserving winner of the 2014 Carbuncle Cup). Large scale stacked use schemes may have a place but raise liveability questions and are difficult to construct: I don’t foresee them arriving in quantity.

Suburban intensification

More promising is the idea of suburban intensification. Much of suburban London is low density: it is largely under-utilised land. But simply observing that large areas of London are low density is not enough. It is true that, were these areas to be rebuilt at the density of Islington or Chelsea, there would be a large increase in housing stock, and without need for high rise. But these areas cannot easily be rebuilt wholesale: the land is already divided and owned. Hence one line of investigation is to see if existing households could be helped or incentivised to sell, for higher density replacement development. But even taking an optimistic view, land release here is likely to be slow.

Council estate redevelopment

Perhaps most promising of all is redevelopment of low density council estates (and some are low density overall despite inclusion of high rise). This type of redevelopment is already happening in several central London boroughs (I live in the recently redeveloped Myatt’s Field North, Lambeth), and the model could be extended to outer boroughs. It is politically sensitive, and tends to be described as ‘social cleansing’ if existing council homes of similar quantity and quality are not re-provided in the new development. There is a risk that sites that are made available in this way will be unpopular with purchasers, who do not always want council tenant neighbours; this, in turn, pressures developers to reduce or exclude the social housing component. And again the land is not empty, it is built; hence there is sometimes a risk to significant existing architecture, such as Robin Hood Gardens in Poplar, East London, which is to be demolished as part of an estate intensification scheme. This is a conservation issue, which should be weighed against the desire to retain green belt: is it really better to sacrifice a good example of modern housing over even the lowest quality green belt?

Council estate redevelopment at higher density – combined with whatever can be gained from suburban intensification – can help to grow the city while leaving the green belt untouched. But is it enough? And are advocates of this route to growth adopting a balanced, moderate, or fair position? When combined with fastidious preservation of green belt, advocacy of estate redevelopment looks partisan. Advocates of this route only to growing the housing supply are open to the accusation that they favour one constituency, those who enjoy green belt adjacency, over others; those who live in and around council estates, and those who live in suburbs targeted for densification.

3: Escape from urban life

A final argument for leaving the green belt untouched is that it provides essential amenity – an escape from urban life. I agree that some of it does: I spend plenty of my weekend days biking up and down the Surrey lanes popular with cyclists. However, a point made by Howard – the originator of the garden city idea – still stands: the ‘countryside’ is often not accessible. It has open spaces but also ‘no trespassing’ signs. Knowing that much green belt is farmland, this shouldn’t be surprising: farmland is rural industry; someone’s productive resource, not a leisure resource. And then there are the golf courses and country clubs; also typically enclosed, with no right of access. There is also the issue of infrastructural barriers to access: the green space exists, and perhaps you have the right to go there, but can you as a practical matter get there?

Howard answered both of these challenges with one idea: the garden city would enfold the green, developing some as housing and employment and making the rest more accessible than before, both as a matter of right, and physically. Howard is often taken for an advocate of the suburb but he envisaged small, relatively dense and delimited settlements, interspersed with a mix of public parks and farmland, and linked by fast rail connections. Compactness produces practical variety: if you live two hundred meters from a green space, you are likely to be able to go there often. Rail connections give further choice: if you are bored with the settlement where you live, and with its amenity offer, you can quickly travel to another. His emphasis on rail as a key enabling technology is in part down to context – cars existed only as prototypes when he wrote Tomorrow (published 1898) – but increasingly, rail – efficient, sustainable – is vindicated as the transport mode of choice. But new rail links are only justified when they serve development. Counter-intuitively, development – by bringing the railway – helps with the escape from urban life.


There is huge demand for housing in London. Although the green belt brings certain benefits – principally leisure – through restricting supply it also harms. As it stands, green belt legislation is bad policy. It preserves open land of questionable quality. It preserves land that is often hard to access, undermining the claim that what is being preserved contributes to London’s amenity. Efforts to find non-green belt sites for increasing housing supply not only risk falling short, they risk leading to extremes, such as planning to redevelop most of London’s council estates. That we are contemplating such extreme measures only highlights the unfairness of the institution of the green belt. It deserves reform.