Boiler Plus Regulations Explained for London Landlords

What Is Boiler Plus?

Boiler Plus is the name given to the requirements introduced under the Energy Efficiency (Private Rented Property) (England and Wales) Regulations 2018, effective from 6 April 2018. The regulation mandates that any new combi boiler installed in England must incorporate at least one additional energy efficiency measure beyond the boiler itself.

The regulation was introduced to reduce the energy consumption of the 12.7 million combi boilers in the UK — which represent the most common heating system in London rental properties. Combi boilers with better controls waste less energy on heating that is not needed.

What Counts as a Compliant Efficiency Measure?

Four measures satisfy the Boiler Plus requirement — at least one must be installed with any new combi boiler:

• Time and temperature zone controls: The heating system must be capable of independently controlling temperature in different zones (typically, separate upstairs/downstairs or living/sleeping zones). This is achieved with a two-zone programmer and two sets of thermostatic radiator valves (TRVs) or a room thermostat in each zone.
• Smart thermostat with automation and optimisation functions: A thermostat that can be remotely controlled and that includes auto-adaptation (learning usage patterns or adapting to weather). Nest (Google), Hive (British Gas/Centrica), tado°, and Honeywell Home T6R all qualify.
• Load compensation: A thermostat that adjusts the boiler's flow temperature based on how much heating is actually required. When the room temperature is near the target, the boiler runs at lower flow temperature — reducing cycling and improving efficiency. Available as a feature on certain thermostats (e.g. Worcester Bosch Wave, Hive with load compensation mode).
• Weather compensation: The boiler's flow temperature is adjusted based on outside temperature. Requires an external temperature sensor and a compatible boiler control. More technically involved but highly effective — potentially 5–12% efficiency improvement.

What Does This Mean for London Landlords?

If you are replacing a boiler in a London rental property — whether on a like-for-like basis or as an improvement — the new boiler installation must comply with Boiler Plus. Your Gas Safe engineer is responsible for ensuring compliance and will typically recommend the most practical option for your property.

In practice, the most common compliance route for London rental properties is a smart thermostat (such as Nest or Hive) or a time and temperature zone control (a room thermostat with TRVs on all radiators except the bathroom). Both options are already standard installation practice for most London heating engineers.

Cost Implications for Landlords

• Time and temperature zone controls (room thermostat + TRVs): typically included in a standard boiler installation quote — no significant additional cost if TRVs are already fitted
• Smart thermostat (Nest, Hive, tado°): supply and install adds £150–£350 to the boiler installation cost
• Load compensation: available as part of manufacturer control systems (Worcester Bosch Wave) — typically £80–£200 additional
• Weather compensation: requires external sensor and compatible boiler — typically £200–£400 additional for the sensor and setup

Which Boiler Plus Measure Is Best for London Rentals?

For most London rental properties, a smart thermostat such as Nest or Hive offers the best combination of Boiler Plus compliance, tenant convenience, and landlord benefit (remote monitoring, fewer complaint calls about heating). Nest and Hive both allow the landlord to view heating usage remotely and set minimum temperature schedules — useful for preventing frozen pipes in empty properties.