Existing district heat network
Approved document L, Conservation of Fuel and Power, Volume 2: Buildings other than dwellings, 2021 edition incorporating 2023 amendments, defines an existing district heat network as:
A district heat network that is either in operation or is under construction on 15 June 2022. For these purposes, under construction means any of the following.
- The building to house the energy centre has been constructed.
- There is a heat offtake agreement signed between the heat network and a third party.
- Excavation for pipework has been completed.
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