1.7m 'dirty' UK homes can't improve energy efficiency in blow to net zero plans

Some 1.7 million UK homes have a very poor energy efficiency rating that cannot be improved, new data revealed, amid ambitious net zero plans by the government.

The government hopes to reduce the country’s emissions by 78% by 2035 compared to the 1990 level, and bring the UK more than three-quarters of the way to net zero by 2050.

It also wants to have as many homes as possible reach a C rating by 2035 in England and Wales, with a target of 2030 for private rented homes.

However, new analysis by property website Rightmove (RMV.L) has found that there are about 1.7 million homes currently rated between D and G for energy efficiency that cannot be improved to reach a C rating.

It also found there are some further 11 million homes in England and Wales that do not yet have an Energy Performance Certificate (EPC) rating, likely as they haven’t been sold or let out since the certificates were introduced.

When a home is built, sold or rented in the UK, it needs an EPC. This shows you how much a building will cost to heat and light, what its carbon dioxide emissions are likely to be and what improvements can be made to improve its energy efficiency.

Read more: UK motorways to get 1,800 new car charging points in £300m green investment

New-build homes tend to have high EPC ratings, while older homes often have lower ratings of around D or E. The average EPC rating for a home in the UK is D, according to consumer group Which?.

“Some lenders are now starting to introduce green mortgages as incentives, but homeowners need to be better informed that how green your home is will become increasingly important as we aim to move towards a net zero society, and they need more help to understand why making improvements are so important for the long term," said Rightmove’s director of property data Tim Bannister.

Rightmove’s EPC study analysed the energy efficiency ratings of over 15 million homes.

Across England and Wales, 59% of homes have a D, E, F or G rating and there is the potential for this to be reduced to 11% of homes if recommended improvements were made, the study said.

Crawley has the potential to drop to the lowest proportion of homes with a rating of D or below if improvements were made, which would reduce the proportion from 47% to just 5%.

Tower Hamlets (27.4%), Hackney (39.2%) and Southwark (41.7%) are the top performers for the lowest proportion of properties with a current rating of D or below.

The most common improvement that is recommended in EPCs is to install solar panels, although these will cost thousands of pounds, the report said.

The second most common recommendation, mentioned in over five million EPCs, is to switch to use low energy lighting. This is one of the cheapest ways that can help improve energy efficiency.

Watch: The £2bn Green Home Grants scheme explained