64% of FTBs in the UK, and 73% in London, believed it was important to live in a home with an EPC rating of C or above, according to Fairview New Homes.
Only 2% said they would pay significantly more for an efficient property, while 26% said they would pay a little more.
Southwark followed with a score of 9.63, with 77% of homes rated A to C and 297 installers per 10,000 D to G rated homes.
50% said EV charging was important, 47% said smart technology, and 43% said solar panels.
The lender is offering 1,000 free property assessments aimed at showing landlords what improvements are needed to reach an EPC ‘C’ rating.
Michael Davey said: "Reducing the environmental impact of housing is no longer a future challenge – it is one of the biggest climate opportunities in front of us today."
The three-year scheme will target homes that need the most improvement, aiming to bring all properties up to at least an EPC rating of C.
The data from Emperor Paint revealed that 55% of properties fall into bands D to G, indicating average to very poor energy efficiency.
The first homes are expected to be finished in Autumn 2026.
Robert McCoy said: “Partnering with eco-Landlord allows our members to offer practical, forward-looking support to landlord clients."
The study showed new builds are 21% cheaper to run, with average annual energy costs at £1,574, compared to £1,995 for older homes.
The organisation is calling for a clear roadmap for non-domestic energy standards, alongside a more flexible approach for the private rented sector.