Minimum Energy Efficiency Standards decide whether you can legally let a property. They are also the area where landlords get the worst advice, usually from people quoting a deadline that has moved.

Where the rules stand now

It is currently unlawful to grant a new tenancy — or continue an existing one — on a domestic property rated F or G, unless a valid exemption is registered. Band E is today's working minimum.

That changes. The Warm Homes Plan, published in January 2026, confirmed a firm date: privately rented homes in England and Wales must reach a C-equivalent standard by 1 October 2030. This is no longer a consultation or a proposal — the deadline is set, after several years of it moving.

Two details matter as much as the date:

  • The cost cap rises to £10,000 per property, up from £3,500. That is a substantial increase in what a landlord can be expected to spend before an exemption applies.
  • A secondary standard applies too. Alongside the C-equivalent rating, a property must meet either a heating system performance standard or a smart readiness standard — with the landlord choosing which.

Roughly 60% of privately rented homes currently sit at D or below, so this is the majority of the sector rather than a stragglers' problem.

Why the ten-year rule matters more than the deadline

Certificates last ten years, and a property rated C before 1 October 2029 is treated as compliant until that certificate expires. Work done now can therefore carry you past the 2030 deadline without a second assessment — which is a real argument for finding out where you stand while there is still time to plan the work rather than rush it.

Exemptions that actually exist

  • All relevant improvements made — you have done everything that can be done within the cost cap and the property still falls short.
  • High cost — the improvements would exceed the cap that applies.
  • Consent — a tenant, lender or freeholder has refused permission.
  • Devaluation — evidenced by an independent surveyor.
  • Wall insulation — where an appropriate expert says it would damage the property.

Exemptions must be registered on the PRS Exemptions Register to have effect. An unregistered exemption is not an exemption, and this is the most common enforcement failure we see.

The London problem

Much of London's rental stock is solid-walled Victorian terrace and converted flats, where the cheap wins simply do not exist. There is no cavity to fill. The measures that move these properties are loft insulation where a loft still exists, heating controls, a modern boiler, and glazing — and in conservation areas the glazing is often off the table.

The hardest stock of all is the electrically heated ex-council flat. Old storage heaters weigh heavily in the calculation because of how electricity is costed, and replacing them is usually the only thing that moves the letter. That is a planned capital job, not a weekend.

If you own several flats in one building

Do not assume one certificate tells you about the others. In a converted house, the top-floor flat carries the roof and the ground floor carries the floor, while the middle flat loses heat through neither. They routinely land a band apart on identical construction. Each dwelling needs its own assessment.

If you let in London, the useful first step is knowing the real number rather than an estimate. You can book online per property, and we will tell you plainly which improvements are worth the money and which the certificate will recommend but planning will never allow.