Building new homes under a ‘business as usual’ scenario, combined with current trends to make existing homes more efficient, would mean the housing system would use 104% of the country’s cumulative carbon budget by 2050. Radically rebuilding existing homes, reducing the number of second homes, dissuading people from buying homes as financial investments and giving people to live in smaller buildings would be more sustainable ways of dealing with the housing crisis, the paper says. The carbon budget is the cumulative amount of emissions that a country can emit in a given period. England’s 1.5C budget means limiting total emissions to 2.5 gigatonnes of CO2 between 2022 and 2050, say the researchers, who have not looked at the comparison in Scotland, Wales or Northern Ireland, but believe it is likely to it’s a similar picture. “In the longer term, we argue that England cannot keep building new homes forever and needs to start thinking about better and more systematic solutions to how we house everyone within our environmental limits,” said lead researcher Dr. Sophus zu Ermgassen, from the Durrell Institute of Conservation and Ecology at the University of Kent. The paper, published in Ecological Economics, is the first to comprehensively analyze the impact of the government’s response to the housing crisis on national carbon and biodiversity targets. The researchers write: “Safe housing is a fundamental human right. However, potential conflicts between housing and sustainability goals remain underexplored.” They looked at two existing models, one to assess the emissions needed to run homes in the UK and the other, emissions from building new homes. The figures come from looking at trends in decarbonising housing between 1990 and 2019, meaning housing will be 50% more efficient by 2050. For England, if current trends continue, 92% of emissions will come from existing homes and 12% from emissions from building and running new homes, the study finds. There are around 25 million homes in England and the amount of emissions from existing homes is high because large parts of the housing stock are pre-war and harder to insulate. For example, half of the houses built between 1919 and 1930 have uninsulated solid walls that account for almost half of the heat loss. The thermal image of terraced houses in Guildford illustrates the energy cost of heat loss. Photo: Jason Alden/Bloomberg/Getty Images The researchers looked at the biodiversity and climate impacts of these ongoing trends. “Our scenarios show how drastic the problem is and how ambitious the solutions need to be if we want to stay within our 1.5C carbon budget,” said Ermgassen. The paper also warns that policies to protect wildlife will need to be “very effective” if housing is not to undermine the government’s big biodiversity target of halting species decline by 2030. The government has pledged to implement legally binding targets to halve wildlife decline by 2030, which requires all new developments to have a “net biodiversity gain”. Globally, 24% of threatened species on the IUCN Red List are threatened by commercial and residential buildings. Retrofitting the existing stock to make all homes carbon-neutral by 2050 would save 38% of the cumulative carbon budgets for 1.5C, the researchers say, adding that this is “by far the most impactful policy for reducing conflict of housing with the climate goals”. Meeting housing needs without rapidly expanding the housing stock is theoretically possible, although the paper did not look at how many houses the government would have to build. Using data from the English Housing Survey, researchers estimate there are 1.2 million empty or underused homes. Dr Kate Simpson from Imperial College London, who was not involved in the study, said: “This is an ambitious paper which highlights some of the big problems with the current UK housing system, our collective lack of a coherent strategy for covering carbon budgets. and fundamental biodiversity considerations. We urgently need more united thinking like this. “As my research is on home renovation, I agree that we need to find incentives to reuse empty homes, protect the embedded carbon of existing homes and prioritize retrofitting efforts to reduce energy demand, ensuring affordable housing and comfort for all. “ Find more coverage of Age of Extinction here and follow biodiversity reporters Phoebe Weston and Patrick Greenfield on Twitter for all the latest news and features
