Section 5: Rebuilding the nation · Chapter 21
The Retrofit Blitz
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We’ve discussed the economics, shown where the money comes from. Where do we start fixing things? A comprehensive, street-by-street national home insulation programme. We call it the Retrofit Blitz.
Britain has some of the oldest, coldest, and leakiest housing stock in Western Europe. Every winter millions of citizens blast expensive, imported gas through their boilers to heat their radiators, only for that heat to escape straight through their uninsulated walls and single-glazed windows. It is a catastrophic waste of energy, a major source of carbon emissions, and a primary driver of the cost-of-living crisis.
Successive governments have offered small scale stop-start schemes. We should replace this piecemeal approach with a comprehensive state-directed industrial rollout.
Instead of waiting for individuals to apply, local councils or regional authorities will be contracted to retrofit entire streets at a time. Teams of specialised workers will move down a neighbourhood systematically, installing high-quality external wall insulation, loft insulation, double glazing, and smart energy management systems. Where it works for a building, we should install heat pumps and microgeneration such as solar panels. Doing this at a civic scale creates demand certainty, economies of scale, and an efficient supply chain.
“Modelling submitted to Parliament puts the return on large-scale retrofit at £3.20 of GDP and £1.25 of tax for every pound of government investment.”
That is the optimistic end of a range. At the other end sits the OBR’s working assumption of a pound of GDP per pound spent, returning 40p in tax. Chapter 19 sets out why the range is so wide, and why the case holds at either end.1
That multiplier doesn’t leak abroad. You can outsource electronics manufacturing to Vietnam. You can’t outsource the insulation of a Victorian terrace in Newcastle or Leeds. Every pound of off-market credit spent on retrofit lands in the wages of local surveyors, scaffolders, heat-pump engineers, and electricians. It stays in the homes it’s spent on, feeds the local high street, and boosts the regional tax base.
This isn’t theoretical. Sunderland tried it. From 2013, the housing association Gentoo ran a scheme called Boilers on Prescription – GPs referring patients with cold-related respiratory conditions straight into home retrofits. New boiler, double glazing, insulation, for about £5,000 a property. The results, in Gentoo’s own figures: GP appointments among those patients fell 60%. Emergency admissions fell 25% and visits to A&E fell by 30%.2
It’s easy to miss how much that’s worth. Free at the point of use doesn’t mean free. A patient admitted to hospital with a COPD flare-up typically stays three days, and costs the NHS somewhere between £1,900 and £5,000 each time.3 Cut a quarter of those admissions across a street, a town, a region, and the savings stack up fast – money the NHS never has to spend treating an illness that a warm, dry house would have prevented in the first place. And these savings are on top of the multiplier quoted above.
The downstream savings are permanent. Energy bills drop for ordinary families, recycling millions of pounds of disposable income back into our high streets. Lives are saved, cold-related admissions to our overstretched NHS hospitals plummet, and the nation’s total energy demand drops permanently.
“Retrofitting Britain lowers our bills. And it lowers global emissions. This is national security.”ther the money exists. It is what we are prepared to do with it.
- Washan, P., Stenning, J. and Goodman, M., Building the Future: The Economic and Fiscal Impacts of Making Homes Energy Efficient, Verco and Cambridge Econometrics, October 2014. The modelling projects £3.20 of additional GDP and £1.25 of tax revenue per £1 of government investment, a 0.6% relative GDP improvement by 2030 worth £13.9 billion in that year, up to 108,000 net additional jobs, and a 26% reduction in natural gas imports — the principal driver of the GDP effect. The report was sponsored by a coalition including the Energy Bill Revolution, Kingfisher plc, the Mineral Wool Insulation Manufacturers Association, the Sustainable Energy Association, the UK Green Building Council and Willmott Dixon; the modelling was carried out by Cambridge Econometrics and has been cited in written evidence to several parliamentary select committees. Subsequent modelling by Cambridge Econometrics for Greenpeace in 2022 reached comparable conclusions.
The modelling dates from 2014 and its central mechanism is import substitution, so the value of the projected gain moves with gas prices and should be read as indicative of direction rather than as a current estimate. ↩︎ - Gentoo Group Annual Report 2015/16. The Boilers on Prescription scheme, run in Sunderland from 2013, referred patients with cold-related respiratory conditions into home retrofits at a cost of approximately £5,000 per property, and recorded a 60% reduction in GP appointments, a 25% reduction in emergency admissions and 30% reduction in A&E attendance among participants. ↩︎
- Academic Health Science Network case study on COPD admission avoidance, which puts the cost to the NHS of a COPD-related hospital admission at £1,900 to £5,000 per patient per admission. NHS Digital data indicates a median hospital stay of around three days for COPD exacerbation admissions. ↩︎