MEES = Minimum Energy Efficiency Standards. Introduced in 2018, MEES makes it illegal to let a property in England and Wales that doesn't meet a minimum EPC rating.

Current rule (in force): All let domestic properties must have at least an EPC E rating. This applies to new tenancies and renewals since April 2018, and to all existing tenancies since April 2020.

Upcoming change: Government has confirmed that the minimum will rise to EPC C — for new tenancies from April 2028, and for all existing tenancies from April 2030.

Spending cap: Landlords are not required to spend more than £10,000 (inclusive of grant funding received) to bring a property up to standard. If you've spent £10k and still can't get there, you can register a cost-cap exemption.

Penalties: Up to £5,000 for non-compliance under the current E rule. Penalties for the upcoming C rule are expected to be higher — government has consulted on £30,000 per breach.

Sources: The Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2015, BEIS Consultation on Energy Performance of Buildings (2020+).

Typical SAP point gains by measure:

• Cavity wall insulation: +6 to +12 points (£1,000–£4,500, often grant-funded)
• Loft insulation (none → 270mm): +4 to +8 points (£900–£2,500)
• Internal/external wall insulation (solid wall): +8 to +15 points (£4,000–£15,000)
• A-rated boiler: +4 to +8 points (£2,500–£3,500)
• Air source heat pump: +5 to +10 points (£10–£14k; £7,500 BUS grant)
• Solar PV (4kW): +4 to +8 points (£6,000–£8,000)
• Double/triple glazing: +3 to +6 points (£4,000–£10,000)
• LED lighting: +1 to +2 points (under £200)

To lift a property from E to C you typically need 14–25 SAP points. From D to C, around 8–13 points.