A quick guide to HNTAS – the Heat Network Technical Assurance Scheme
The UK government is consulting on new performance requirements for heat networks, which are set to affect the entire heat network supply chain.
From 2027, heat networks will be subject to formal technical standards and certification under the Heat Network Technical Assurance Scheme (HNTAS). The changes are likely to impact heat suppliers and network operators, landlords of communal heating systems, developers, designers, contractors, local authorities and other consultancies involved at any stage of a network’s lifecycle.
We’ve written a quick guide to HNTAS to help you understand what it means for you.
What is HNTAS?
HNTAS sets the technical requirements that new and existing heat networks must meet, alongside an assessment and certification process to ensure compliance. The new consultation outlines the scope of these, with regulation coming into force in 2027. The consultation closes on 15 April 2026.
HNTAS standards are largely based on CIBSE CP1 (2020) and new supporting documents, including the Heat Network Technical Standard (TS1), and a new Metering and Monitoring Standard.
Compliance applies to each stage of a network’s lifecycle (including feasibility, design, construction and operation).
Why HNTAS is needed
Evidence of poor heat network performance and consumer outcomes has driven the move from voluntary guidance to mandatory regulation. Heat networks are expected to grow rapidly and be treated as a regulated utility, with stronger consumer protection and performance assurance.
What is in scope of HNTAS?
Both new and existing heat networks (district and communal) are likely to be in scope. The consultation proposes a minimum size:
- Domestic networks serving 6 or more properties
- Non-domestic or mixed-use networks –450kW connection capacity threshold for existing networks, and 225kW for new networks
- Ambient loop and shared ground loop networks are included, with requirements under development.
Industrial heat networks are excluded with possible future inclusion.
What will be assessed?
Six elements of the heat network system will be assessed:
- The Energy Centre – e.g. the plant room containing heat generation equipment (heat pumps, CHPs), boilers and BMS/control equipment
- District Distribution Network (e.g. pipework, valves, heat meters)
- Substation
- Communal Distribution Network (e.g. pipework, valves, heat meters)
- Consumer Connection (e.g. hot water storage, meters and monitoring equipment)
- Consumer Heat System (e.g. radiators, AHUs, fan coil units, underfloor heating, hot water systems)
Each element will have minimum requirements at every lifecycle stage.
Metering and monitoring
HNTAS places strong emphasis on heat metering and performance monitoring. Networks will need metering at the energy centre, building entry points and dwelling level, supported by automated and remote monitoring systems to report KPIs and evidence compliance.
Responsibility and enforcement
Ofgem will be the regulator for HNTAS. Each network must have a named Responsible Party (typically the operator) accountable for meeting HNTAS requirements.
DESNZ will act as Code Manager, overseeing the scheme.
Existing heat networks have more time to comply
DESNZ says it recognises the cost and disruption of upgrading legacy networks. Existing schemes will follow a less stringent, phased pathway, with transitional milestones over several years rather than immediate compliance with new-build standards.
Incentives and opportunities
DESNZ is considering financial and non-financial incentives, recognising the cost of compliance:
- Grants and/or financial support for installing equipment required by HNTAS, such as metering and monitoring equipment or HIUs
- Grants and/or financial support for undertaking services required by HNTAS(e.g. the development of Performance Improvement Plans or subsidised assessment costs).
- Financial incentives for early movers toward HNTAScertification
- Deadline extensions for early movers with very large portfolios
- Fast tracks to encourage early adoption and certification under HNTAS
- Subsidised training to support all the above
What happens next
Consultation and technical feedback continue during spring 2026.
Final standards, guidance and assessor training are expected in 2027, ahead of HNTAS coming into force that year.
Advice and support
HNTAS represents significant new responsibilities for the heat network supply chain, including network operators and landlords of communal systems.
Concept’s consultants have undertaken HNTAS training and bring extensive experience across heat network feasibility, design review, performance optimisation and compliance.
We can:
- Help you understand your obligations under HNTAS
- Review existing networks to identify compliance gaps and performance improvements
- Assist with compliance administration and documentation
- Help you access funding for heat network upgrades
- Help ensure your heat network is technically robust and ready for certification
If you have questions about how HNTAS will affect your organisation, or would like support preparing for compliance, get in touch.
