Few things in life are certain. That the taxman will want his share. That, one day, you will die. And that, within three minutes of any discussion of how to solve Britain’s housing crisis beginning, someone who thinks they are clever will use the word “brownfield” as if it amounts to an answer and not simply a declaration that they haven’t done the reading. Which is what it actually is.

Brownfield, for those who haven’t had the pleasure, does not literally mean brown fields. In British planning circles, it generally means land that has been developed in the past, in some way or another. Often it’s used more colloquially as if it carries a more specific mean, that of “former industrial land” – depressing looking places of the sort which nobody would mourn if they were redeveloped as housing.

The idea of redeveloping brownfield as opposed to virgin, ‘greenfield’ land is an attractive one. It means keeping our towns and cities compact; regenerating abandoned sites; and protecting the great British countryside, all rolled into one. Why wouldn’t you favour a brownfield first housing policy?

Well, actually, there are several reasons why one wouldn’t. Some brownfield land is in places people don’t actually want to live, so is effectively of no use whatsoever. Some is, confusingly, too green to be worth concreting: there are brownfield sites in North Kent that are currently nature reserves. And some brownfield land was so contaminated by industrial uses that government can either spend a fortune to clean it up or risk weeks of headlines about the sudden appearance of kids that glow in the dark like the Midwich cuckoos.

Strong arguments all. But there’s a bigger, simpler retort to the brownfield first argument: we’ve tried it, and it hasn’t worked. And a significant reason for that is that there isn’t enough of the bloody stuff.

A couple of weeks back, the National Housing Federation, the umbrella group for housing associations, published an interactive map of all England’s brownfield land. It’s fun, if you’re into that sort of thing. Here’s central London:

 

And here’s Liverpool, with details of one site pulled up:

As fun as the map is, though – which it definitely is – the more important point is the figures that accompany it. The NHF found more than 17,000 brownfield sites in England, totalling around 27,700 hectares. At average densities – which, extrapolating, the researchers assume to be around 35 homes per hectare – that would be enough land for around 961,683 homes.

Which, as the NHF’s executive director Simon Nunn notes, is a bit of a problem:

“England is short of four million homes. If we’re to meet this demand by 2031 we need to build 340,000 homes every year…

“Even if this map can help housing associations build more quickly on brownfield sits, there is only enough brownfield land in the country to build a million new homes. This is of course significant, but it is not enough to end the housing crisis altogether.”

The NHF’s conclusion is that actually meeting housing targets will mean looking beyond brownfield, and expanding the land on which we build:

“We also need to look at building homes on disused public land, as well as sites that have not been built on before. This will have to include some parts of the Green Belt where appropriate”

I am shocked. This is me looking shocked. This is my shocked face.

There’s stuff in this report that one could argue with. For one thing, I’m not sure it’s comprehensive. There is not a single site in the London borough of Havering, which seems unlikely to me, so I suspect there’s stuff it’s missed:

One could also argue that, at a time of crisis, we should build at higher than average densities – on which basis perhaps there is room for more than a million homes here. And, actually, there is another option, which the NHF ignores: to, in effect, create more brownfield, by knocking stuff down and rebuilding at higher densities than before.

But there are obvious responses to all of these questions. People don’t want to live at higher than average densities. If the NHF has missed some brownfield sites, it seems unlikely it’s missed the enough to undermine its basic point. And if you think building on greenfield is unpopular, wait until you try telling people that the solution to the housing crisis is to demolish their low-rise homes.

So the basic point remains. We should build on brownfield over greenfield, where possible. But it’s not actually a solution to the housing crisis. And the idea we can fix this mess without taking some hard choice is nothing but a comforting lie, put about by people who haven’t done their research.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.

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