Heat network regulation: what it means for a block of flats
Since 27 January 2026, Ofgem has regulated heat networks in Great Britain, and that includes communal heating in a block of flats. A block where one central plant supplies heating or hot water to separate flats is usually a communal heat network. Its operator and its supplier must register the network with Ofgem by 26 January 2027.
What changed on 27 January 2026
The rules come from the Heat Networks (Market Framework) (Great Britain) Regulations 2025. Ofgem’s regulation of heat networks began on 27 January 2026, when new consumer protection rules took effect.
Heat networks already running on that date were automatically authorised to carry on supplying heating, cooling or hot water. Ofgem calls this deemed authorisation. It does not replace registration: the operator and the supplier of each network still have to register it by 26 January 2027.
Which buildings count as a heat network
Ofgem sorts heat networks into two kinds:
- a communal heat network supplies heating, cooling or hot water to a single building divided into separate premises, such as flats
- a district heat network supplies heating, cooling or hot water to 2 or more buildings
A block with one boiler house serving every flat is a communal network. An estate where one energy centre serves several blocks is a district network.
Ofgem also lists cases that do not need to register, including:
- a single house in multiple occupation with a shared heating system
- a converted building divided into flats, with one energy source of no more than 45 kW of thermal capacity
- a single building with shared facilities that is not divided into separate premises, such as a care home
- a communal network that gives heating and cooling only through air conditioning and supplies no hot water
The full list is on Ofgem’s page on who needs to register a heat network.
Operator and supplier
Ofgem defines two roles for each network:
- the operator is the organisation that has control over and responsibility for the transfer of heat on the network, for supplying heating, cooling or hot water
- the supplier is the organisation responsible for the contractual and customer facing arrangements for supplying heating, cooling or hot water to the people on the network
The same organisation can hold both roles. Ofgem says each organisation involved should check what it does against those definitions to work out whether the operator or supplier duties apply to it, and the operator and supplier of each network must be identified when the network is registered.
The dates
- 27 January 2026: the rules took effect, and networks already running were given deemed authorisation.
- 26 January 2027: operators and suppliers must have registered, giving Ofgem details of the network’s organisation, ownership, financial resilience and consumer protection arrangements.
Registration is done online: Ofgem has launched a digital service for operators and suppliers to register their networks and tell it about their organisation.
What does not change
Regulation by Ofgem sits beside the duties a block already had. It does not replace them.
- Where flats are rented, a communal gas boiler that serves them still needs the yearly landlord gas safety check under regulation 36 of the Gas Safety (Installation and Use) Regulations 1998. See whether a communal boiler needs a landlord gas safety check.
- BS 6644 still sets how gas boilers of more than 70 kW and up to 1.8 MW net input are installed and maintained, including groups of smaller boilers that add up to more than 70 kW.
- In England, works that will cost any leaseholder more than £250 still need a section 20 consultation under the Landlord and Tenant Act 1985. See section 20 and communal boilers.
Plant records and where Neos Engineering fits
Separately from registration, a block needs its own record of the plant: each boiler, pump and pressurisation unit, its age and condition, and its service history. A condition survey produces that record, and it helps when budgeting for a replacement.
Neos Engineering maintains plant rooms, communal boilers and heat networks across all of London, with planned servicing, combustion checks, flue testing and condition surveys. The work is priced after a site survey, with a written quote before anything is booked. Registering with Ofgem is the operator’s and the supplier’s job, not the maintenance contractor’s. To arrange a survey, see plant room maintenance or contact the office.
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