For developers, operators, asset owners and suppliers, HNTAS will represent a step change. From 2027, heat networks will be required to meet mandatory technical standards, backed by formal assessment and certification. This will apply not only to new schemes, but also to much of the existing estate.
This news is important for owners and operators of networks where Building Management Systems (BMS) are part of the heat network’s control and monitoring systems — specifically as part of the energy centre and substation elements.
What is HNTAS?
HNTAS sets out the technical requirements that heat networks must meet, alongside a framework for assessment and certification to demonstrate compliance. The scheme is largely based on CIBSE CP1 (2020), supported by new documents including the Heat Network Technical Standard (TS1) and a newly published Metering and Monitoring Standard. Importantly, compliance is not limited to design alone. HNTAS applies at every stage of a network’s lifecycle, from feasibility and design through to construction and long-term operation.
Why regulation is being introduced
The shift from voluntary guidance to mandatory regulation has been driven by consistent evidence of poor performance across parts of the sector. Issues such as high heat losses, inefficient operation and weak consumer outcomes have undermined confidence in heat networks. At the same time, heat networks are expected to expand rapidly as part of the UK’s net zero strategy. The UK Government's policy is therefore to treat them as a regulated utility, with stronger performance assurance and consumer protection.
Which heat networks are in scope?
The HNTAS consultation proposes that HNTAS will apply to both district and communal heat networks, subject to minimum size thresholds. Domestic networks serving six or more dwellings are expected to fall within scope. For non-domestic or mixed-use networks, the proposed thresholds are 450 kW of connection capacity for existing schemes and 225 kW for new ones. Ambient loop and shared ground loop networks are also included, although some requirements are still being developed. Industrial heat networks are excluded for now, but may be considered in the future.
What will HNTAS assess - and are BMS in scope?
In short, yes, BMS are in scope if they are linked to heat networks. HNTAS takes a whole-system approach. Rather than focusing only on generation plant, it assesses six elements of the heat network system, from the energy centre and distribution pipework through to consumer connections and internal heat systems. Each element will have minimum requirements at each lifecycle stage. In practice, this means that everything from plant room controls and BMS, to substations, meters, HIUs and in-home heat emitters, will be subject to technical standards.
Metering and monitoring move centre stage
One of the most significant changes introduced by HNTAS is the emphasis on metering and performance monitoring. Networks will be expected to install heat metering at the energy centre, at building entry points and at dwelling level. These meters must be supported by automated and remote monitoring systems that can report performance data and key metrics. The aim is to move the sector towards evidence-based performance management, rather than reactive problem solving.
HNTAS as an opportunity: what will happen to existing networks?
The Government recognises that upgrading legacy networks can be costly and disruptive. As a result, existing schemes are expected to follow a phased and less stringent pathway to compliance, rather than being held immediately to new-build standards. The Department for Energy Security and Net Zero (DESNZ) is also considering financial and non-financial incentives to support compliance. These may include grants for metering and monitoring equipment, support for developing performance improvement plans, and incentives for early movers. It is currently unclear if there will be financial incentives and support to upgrade legacy BMS systems - however, we further detail is expected as the consultation progresses.
What happens next?
Consultation and technical feedback will continue through spring 2026. Final standards, guidance and assessor training are expected in 2027, ahead of HNTAS coming into force later that year. HNTAS will fundamentally reshape expectations around heat network performance and accountability. For organisations active in the sector, the consultation period offers a critical window to engage, influence the final framework and begin planning for a regulated future.
