The temperature hit 32°C in Cambridge last week. For the 19 million UK homes built before 1980, that means solar gain turning bedrooms into ovens and fans running through the night. It also means a spike in electricity demand that the grid is not designed for. As reported by BusinessGreen, heatwaves and rising energy bills have pushed home efficiency back into the political spotlight. Tony Blair’s Institute has added its voice, calling for a national retrofit programme that would insulate millions of homes and install heat pumps at scale. But for the homeowner staring at a £2,200 annual bill, the question is not whether the policy sounds good. It is: what can I do now?
Why heatwaves expose the retrofit gap
The UK’s housing stock is the oldest and leakiest in Europe. A typical 1930s semi loses heat at three times the rate of a modern passive house. In summer, that same lack of insulation turns the loft into a heat trap. The Energy Saving Trust estimates that topping up loft insulation from 100mm to 270mm saves around £35 a year on heating, and keeps bedrooms 2–3°C cooler in a heatwave. Yet fewer than one in five homes has adequate insulation. The catch is that most retrofit policies focus on winter savings, ignoring the summer penalty. Blair’s proposal, as outlined in a report from the Tony Blair Institute for Global Change, calls for a 10-year, £200bn programme to retrofit 29 million homes. But the report does not specify how much of that money reaches individual households, nor does it address the immediate cost of cooling during a heatwave.
What the Blair plan would mean for your EPC
An Energy Performance Certificate rates homes from A to G. The UK average is D. Getting to a C typically costs £5,000–£15,000, depending on the property. The Blair plan proposes a ‘Retrofit UK’ body to coordinate grants, low-interest loans, and a national skills programme for installers. Ofgem data shows that the current Boiler Upgrade Scheme pays £7,500 for a heat pump, but uptake has been slow, just 30,000 installations in 2023 against a target of 600,000 by 2028. The gap is partly because homeowners do not know what grant they qualify for. A single application portal, which the Blair Institute recommends, would help. But without a binding deadline for landlords and a clear subsidy floor for owner-occupiers, the voluntary approach leaves households waiting.
Three actions you can take before the next heatwave
While Westminster debates, your house is still sweating. First, draught-proofing: seal gaps around windows, doors, and floorboards. Cost: £100–£200. Saving: £60–£90 a year. Second, reflective radiator panels behind radiators on external walls. Cost: £15 each. Saving: £10–£15 per radiator. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The scheme covers cavity wall and loft insulation for low-income households and those in council tax bands A–D. Applications are open now via gov.uk. None of these steps require a new government programme. They work with the existing grants and can shave £200–£500 off your annual energy bill while keeping your home cooler in summer.
Who qualifies, and who falls through the cracks
The Blair plan targets owner-occupiers and private renters. But the 4.4 million households in the private rented sector face a specific barrier: landlords have no obligation to improve EPCs until 2028, and then only to a C. The cost often gets passed to tenants via higher rent. Meanwhile, social housing has a separate target of EPC C by 2030. The gap between policy ambition and delivery is widest for the 2.3 million households on prepayment meters, who pay the highest standing charges and have the least ability to finance upgrades. Ofgem’s latest data shows prepayment customers paid £80 more on average than direct debit households last year. Any retrofit programme that does not address this inequality will leave the most vulnerable paying for the transition they cannot access.
The next general election will likely feature retrofit as a manifesto line. But the heatwave is here now. Homeowners should check their EPC, apply for available grants, and start with the cheapest measures. The government’s own analysis shows that every £1 spent on insulation saves £3 in health and energy costs over a decade. That is a return worth taking, regardless of what Tony Blair says.
Frequently Asked Questions
Typically £5,000–£15,000, depending on the property size and current insulation levels. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing.
Not immediately. The proposal is a policy recommendation, not a government scheme. Homeowners should use existing grants like the Boiler Upgrade Scheme and Great British Insulation Scheme to reduce bills now.
