£35k average home retrofit cost ‘demonstrably inequitable’

The report, Decarbonising UK housing: The Regional View by property agent and consultant JLL, estimates the average cost of retrofitting an existing home to EPC Grade C or above is £35,000.

JLL said the figures stood ‘in stark contrast’ to boroughs such as Hackney, in east London, where retrofit costs drops to 6 per cent of the average property value.

Responding to the data, Chloë Phelps, chief executive of Grounded, an architecture practice specialising in regenerating council estates, told the AJ: ‘We need to stop looking at homes as commodities and measure the investment in terms of the long-term benefits retrofit will bring – reduced bills, less reliance on the NHS, as well as carbon reduction.’

He said the disparity in affordability was affecting ‘private homeowners, housing associations, private landlords and local authorities alike’, explaining: ‘Upgrading an existing home is a significant undertaking for individuals, while working at scale can see costs rise to an eye-watering level.’

According to JLL’s research, close to half (48 per cent) of all existing UK properties surveyed in 2023 have an EPC rating of D or below, meaning, JLL says, a ‘significant’ programme of retrofit works will be needed across the country.

Many areas with the widest retrofit equality gaps are in the North – eight of the 10 most heavily impacted areas are in the North East and North West.

According to the report, the cost of retrofitting is likely to exacerbate the housing crisis as ‘fewer new homes will be delivered as cash is earmarked for retrofit rather than building’, while a worst-case scenario would see homes potentially ‘left empty to be demolished rather than upgraded, because of the significant cost versus the resulting value of the property’.

Abdul added: ‘Ambitions need to be redoubled, without overlooking the easy wins. If all stakeholders are prepared to collaborate and be transparent, there is huge long-term environmental, social and economic value to be secured.’


Meanwhile, in separate research published this month the UK Green Building Council (UKGBC) found ‘significant opportunities [are] being missed’ to retrofit commercial buildings.

In Burnley, Lancashire, the average house price across all home types is £130,209, meaning average retrofitting costs would account for 27 per cent of a property’s value. This rises to 50 per cent for flats in the region.

But the company’s residential research team found this was more than a fifth of the average house price in 26 local authorities, leading to a ‘gulf’ in the affordability of retrofits across the UK.

Yetunde Abdul, head of climate action at UKGBC, described retrofitting commercial buildings as ‘critical to achieving our net zero carbon goals’.

Phelps insisted the UK also needed to move away from an ‘all or nothing’ approach to retrofit, saying: ‘There isn’t the funding or capacity to undertake the actual construction work to all homes that need it in the timescales we need to take action […] the best approach will be for people to look to tackle each component as and when the funding is available.’

The sustainability group is urging investors and owners to implement ‘easy wins’ – low-cost, low-disruption measures – to reduce energy consumption and avoid stranded assets and has launched new guidance on retrofitting large office buildings.

Dixon added: ‘There is a clear role for UK government to properly incentivise the private market and support the social housing sector to help decarbonise homes across the country.’

Marcus Dixon, director of UK residential research at JLL, described the situation as ‘demonstrably inequitable when taking into consideration that the homes likely most in need of attention are in areas that are typically less affluent, and less able to shoulder the cost’.