More than 100 rental homes on the royal estates of King Charles and Prince William fail to meet legal minimum energy standards for landlords, a Guardian investigation has revealed.

One in five domestic lets have Energy Performance Certificate (EPC) ratings of F or G on the duchies of Lancaster and Cornwall and the Sandringham estate.

It is illegal to rent out properties with EPC ratings below E, unless the landlord can demonstrate that it is exempt. They must spend up to £3,500 on each property to bring them up to standard or cite an exemption. If they fail to do so, but continue to rent out the property, they could face a £5,000 fine.

In the majority of failing royal rentals, no formal exemption has been cited, according to the report. However, in some cases, the royal estates appear to be using gaps in the regulations to continue letting properties out - this includes the homes of dozens of farmers, who are living in poorly insulated and hard-to-heat farmhouses they lease from the two duchies.

Subject

Some farmhouses are not subject to current regulations, depending on the type of tenancy in place. Other homes rented out by the royals aren’t covered by the rules, as they apply only to tenancies that began after October 2008.

The Guardian visited a number of the worst F and G-rated duchy properties, and found many were affected by black mould, with draughty single-glazed windows. Of more than 200 duchy of Lancaster properties identified, nearly 40 have domestic EPC ratings of F or G. One tenant, who has lived for decades in a property that is rated F, said: “They do no repairs. My windows are so rotten I am scared they will fall out.”

The royals could also be forced to spend up to £10 million upgrading hundreds of properties on their private estates by 2030 when landlords will need to ensure their properties have EPC ratings of C or higher.

The duchy of Lancaster’s recent annual report said making improvements could often be challenging due to the listed or historical status of some of its buildings. It said it placed “great importance” on being a responsible landlord and that during the last year it had invested more than £3 million in residential property repairs and upgrades.

Compliant

A spokesperson said Sandringham “has a mixture of property and tenancy types, which are fully compliant with MEES regulations”. They added: “We continue to invest significantly in an ongoing programme of maintenance and improvement works on all properties, including those out of scope of the regulations, to upgrade energy efficiency across the estate."

More than 80 properties on the duchy of Cornwall estate received F or G ratings on their most recent assessments, said the Guardian. A spokesman said it had spent £11 million on home improvements since 2022 and added: “We will continue to work closely with our tenants to identify effective and practical energy efficiency improvements as quickly as possible.”

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