An estimated 2.9 million properties need to be improved under the government’s proposal for rental homes to reach a minimum EPC rating of C by 2030, costing £23.4 billion – an average of £8,074 per property

The new analysis, revealed in Rightmove’s third Greener Homes Report, also found that half (50%) of landlords say they are concerned about potential financial penalties if rental properties fail to meet EPC C standards by 2030.

The report also revealed that a green wealth divide has emerged – analysing EPCs created over the past year found 50% of £1m plus properties had significantly improved their rating since their previous EPC, compared with only 32% of properties worth under £400,000

In addition, the majority – 72% – of people would be willing to change how and when they use energy if it meant they could access cheaper energy rates at different times of the day

Ahead of the Autumn Budget, Rightmove warns that without financial help to accelerate the upgrades, the move could reduce the availability of rental properties in the market if some landlords choose to sell up rather than make the changes.

The latest real-time market data from Rightmove reveals that the proportion of former rental properties moving into the sales market is already at its highest point on record, suggesting more landlords are selling up. Some 18% of properties for sale in August were previously on the rental market, compared with 8% in 2010.

Rightmove also surveyed more than 14,000 home-owners and renters, along with over 1,000 landlords for the report.

The survey found that while half (50%) of landlords are concerned that the government will introduce costly charges for not meeting EPC requirements, one in five (19%) renters think stricter energy efficiency regulations should be the top priority for the new government.

Ahead of the Autumn Budget, Rightmove is asking the government to consider support for landlords which in turn will benefit tenants, and more mass market help for home-owners of lower value homes

Tim Bannister, Rightmove’s director of Property Science, said: “It’s clear from our analysis that more needs to be done to help the mass market transition to greener homes, especially those living in homes worth under £400,000.

“In the rental market, through discussions with agents and our research, we know landlords want to provide comfortable, energy-efficient homes, but green upgrades can be costly. For landlords of lower-value properties, the financial returns may not always justify the investment.

“Now that the government has confirmed there will be a consultation on raising the minimum energy efficiency standards in rental homes, we look forward to seeing much needed clarity, and ideally support, for landlords, which in turn should benefit tenants over the medium to long term.”

Johan Svanstrom, Rightmove’s CEO, added: “Our Greener Homes Report this year highlights the barriers that remain in the journey to greener homes, from the financial challenges, to the need for clearer guidance on what support is available. It’s clear to us that consumers’ interest in greener options continue to steadily rise.

“At Rightmove, we’ve been increasing our efforts to better educate homeowners, renters, and landlords about the cost and environmental benefits of more energy-efficient homes. By leveraging our extensive data, covering the entire property market across Great Britain, we will continue to support people in making more informed choices and equip the industry with the latest insights into home-mover behaviour.”