The latest attack on landlords by Generation Rent director Baroness Alicia Kennedy concerns insulation and household warmth.

She claims a quarter of a million landlords are letting families live in homes “that are so expensive to heat they are illegal to let out,”

The Baroness claims tenants in these properties spend £321m more on energy bills this year than they would if their homes met what she calls “basic standards.”

South West England is where she claims private renters are most likely to live in a home that fails Minimum Energy Efficiency Standards – nine percent of households, compared with six percent in England as a whole.

The former Labour peer also attacks councils over enforcement, claiming just one in eight local authorities enforce MEES.

The Baroness and her Generation Rent group want councils to identify local private rented homes that fail these standards, and take action to bring them up to standard while giving tenants protection from eviction and a chance to claim back rent.

Generation Rent says it has analysed EPC data to assess the scale of the problem in each region in England. A total of 201,000 homes recorded as private rented are classed as F on their EPCs and 62,000 are classed as G, out of a total of 4,265,000 with an EPC.

Recent research by property consultancy JLL found that following the increase in the energy price cap, the average energy bill for a Band G property is now £4,950 per year and £3,587 for a Band F home.

For a home at the legal minimum of Band E, the average bill is £2,687. Upgrading a Band F home to the legal minimum would therefore save the average tenant £900 per year and upgrading a Band G home is worth £2,263.

Private renters in London are least likely to be in what Baroness Kennedy calls “an illegal home” with 3.3 per cent failing standards, followed by the North East with 4.0 per cent.

Generation Rent made Freedom of Information requests to councils accounting for two thirds of England’s private renter population.

Of the 101 councils that provided information about their MEES enforcement work in 2020-21, just 13 issued enforcement notices, a total of 359. Barnsley Council issued the most notices, with 181, followed by Bristol with 35 and Thanet with 30.

Generation Rent is calling on councils to commit to using publicly accessible data on EPCs to identify tenants in cold homes and all their enforcement powers, including improvement notices, to protect them.

The Baroness herself says: “A quarter of a million households are in homes too cold to be legal and with energy bills through the roof, they are paying hundreds, if not thousands, of pounds more than they should as a result.

“People will miss meals, get ill, and fall into arrears as a result of their landlord’s negligence.

“Councils have the data and the powers they need to protect the most vulnerable tenants – but at the moment most are not using them.

“The government needs to act much faster to ensure that private landlords insulate their properties, including by reforming tenancies to give tenants more confidence to exercise their rights.”