An investigation by The Mirror and Channel 4 Dispatches has revealed that many rental properties owned by Prince William’s Duchy of Cornwall are failing to meet minimum energy efficiency standards, which are legally required for rental homes. Of the Duchy’s roughly 600 properties, approximately 70 have Energy Performance Certificate (EPC) ratings of F or G—the lowest ratings possible. Under current regulations, it has been illegal since 2020 for landlords to rent properties rated below an E without an exemption, putting tenants at risk of high energy costs and fuel poverty, especially in winter.

Several tenants report severe difficulties in maintaining warmth due to poor insulation, with many living in homes that suffer from dampness and black mould. One tenant described his home as “miserably cold,” with only limited heating, while another cited high fuel expenses due to relying on coal and wood, the most expensive heating sources. Properties with EPC ratings of F or G can be costly to heat, sometimes reaching three times the cost of energy-efficient homes, which can be unaffordable for tenants on limited incomes.

Tenant Claire Williams, who lived in her property for over 20 years, shared that her farmhouse in Devon was damp and mould-ridden. She was evicted over disputed rent arrears but claims she was unaware of the property’s low EPC rating until recently. Despite her complaints over the years, the damp and mould have persisted, with any attempts at repainting quickly peeling away. Mid-Devon Council inspectors found conditions of “damp and mould growth” and “excess cold” in her home, serving the Duchy with a “hazards awareness notice” for these issues.

Andrew Parkin, an EPC expert, noted that properties like these are often expensive to heat and produce significant carbon emissions due to outdated, inefficient heating methods. He stated that properties with significant structural gaps are “going to get draughts,” which make them “pretty cold to live in.” Parkin also emphasized that these properties should not be rented out unless they meet energy efficiency standards or have a valid exemption registered.

The Duchy, a private estate previously managed by King Charles III and now by Prince William, has profited significantly over the years, amassing £91 million since the new EPC rules were enacted. The estate has only sought exemptions on 10 properties, typically citing prohibitive repair costs. In response to the findings, the Duchy emphasized its commitment to improving energy efficiency while minimizing impacts on tenants and outlined plans to reach net-zero emissions across the estate by 2032.

However, campaigners argue that the Duchy’s failure to meet basic energy efficiency standards constitutes a serious public health risk, with Jonathan Bean from Fuel Poverty Action calling it “a disgrace” that the estate is “acting like a rogue landlord.” He pointed out that the high heating costs in F and G-rated homes make them unaffordable for many tenants and increase health risks due to the cold and mouldy conditions.