Good news for those who care about housing supply – a team of researchers have found that we can meet our housing target of 300,000 new builds a year, while staying within our carbon commitments.
When modelling the UK’s current housing strategy, they find that, by 2050, just 8% of the total carbon cost of the sector comes from the construction of new homes, with another 3% from operation of those new homes. The remainder, 89% of the carbon cost, comes from the operation of our existing housing stock. The conclusion seems obvious – we need an immediate effort to retrofit and decarbonise our existing housing stock.
Unfortunately, that wasn’t what the researchers concluded. Through their twitter accounts, media reports, and the paper itself, they ignore their own findings completely. Here is the first two lines of the paper:
The primary government response to England’s housing affordability crisis is to build 300,000 new homes per year. Using embodied and operational emissions models we estimate the government’s business-as-usual housing strategy consumes England’s whole cumulative carbon budget [1.5°C] by 2050
A natural reading of this is that the ‘business-as-usual housing strategy’, which consists of building 300,000 new homes a year, will consume England’s whole cumulative carbon budget. But that’s not what the paper demonstrates at all.
Or consider tweets from the researchers about the paper:
Again, I cannot stress enough that this is not what the paper finds. The paper actually found that building 300,000 new houses a year will not blow out the UK’s 2050 net-zero carbon budget (but failing to decarbonise existing houses will). I guess Sophus’ use of the ? emoji is a bit ambiguous, but I don’t think the rhetorical answer to his question was yes.
So what’s going on?
The first thing to note is that this isn’t really a paper about carbon budgets. Of the 14 pages of the paper, a bit less than 1.5 pages cover their carbon model. Another page or so examines biodiversity impacts, and the remainder argues that building houses does not improve housing affordability, a brief digression into the political economy of housebuilding, and a list of possible policy implications.
As you can imagine I strongly disagree with their conclusion that building houses does not affect house prices. But regardless of your views, it’s odd to lump them together into a single research paper. Housing supply might be both a key determinant of house prices, and a critical environmental problem. Or it might be irrelevant to both housing affordability and the environment. The authors construct a narrative against housebuilding – regardless of the fact that their own findings do not support their argument.
The modelling itself shows a similar lack of curiosity. The authors squash together two models, one assessing embodied carbon in construction, and the other assessing embodied carbon in emissions. The models are fine – but the authors show little interest in their applicability to the real world. What happens if we build high-density homes closer to where people want to live, allowing them to use public transport rather than cars? What happens if we assume different speeds of decarbonisation of construction? What if we replace low-density housing with high-density, providing more space for biodiversity? Plenty of our housing stock dates from Victorian times – is it even feasible to decarbonise it fully? The researchers do not spend time exploring the implications and nuances of the argument.
The climate impacts of construction is a serious topic, and deserves scrutiny. There is a genuine question to be asked about how to weigh the benefits of additional construction, with the costs for our environment. Unfortunately, this paper brings us no closer to an answer.
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PricedOut is England’s campaign for affordable house prices. We are the only group campaigning exclusively for policies to bring down the cost of housing for everyone: buyers and renters. We fight for everyone who is priced out of the home they want, where they want to live. We can only do this work with your help. We rely on volunteers so can you spare just just £5 per month to help end the housing crisis?
