Josh Collins at Altecnic Ltd explains the vital role of heat networks in the UK’s journey towards net zero and how architects could be key to ensuring their adoption.
The UK’s Energy Act 2023 paved the way for a new regulatory framework for heat networks; they have a vital role in the UK’s journey to net zero, but performance across the sector has been uneven. Currently being developed by the Department for Energy Security and Net Zero (DESNZ), the Heat Network Technical Assurance Scheme (HNTAS) will introduce mandatory technical standards that ensure heat networks deliver consistent performance, reliability, and efficiency across the UK’s built environment.
Historically, many systems were designed without cohesive guidance, leading to high heat losses, inefficient operation, and variable comfort for residents. HNTAS has been developed to change that by defining measurable design and performance standards for every part of a heat network, from initial generation through to delivery in individual dwellings. The framework will establish minimum expectations for insulation, flow temperatures, commissioning, and maintenance, giving architects and engineers a clear benchmark for compliance and quality.
Why HNTAS matters to architects
While mechanical and electrical (M&E) consultants have traditionally taken the lead on heat network design, HNTAS will bring architects into the process earlier, and more centrally. Design coordination will now influence compliance outcomes.
Design decisions such as plant room location, riser routes, service zones, and facade penetrations all affect pipework length, insulation continuity, and heat loss. By planning these elements from the outset and working closely with M&E specialists, architects can help ensure their developments meet HNTAS efficiency requirements and avoid costly redesigns later in the project.
In practical terms, this means integrating energy centre layouts, secondary network pathways, and consumer connection points within the architectural design to optimise efficiency and space use. Early stage design collaboration will be key to achieving the performance metrics the scheme demands.
A performance-led approach
At the heart of HNTAS lies a shift from theoretical compliance to verified performance, where accountability is taken. Networks will be assessed at several stages of their lifecycle:
- Before design – ensuring concept proposals meet the required performance intent
- Before construction, validating that technical specifications align with HNTAS criteria
- Before operation – confirming commissioning quality and control functionality
- Post-operation – reviewing performance data after two years of operation to verify real world outcomes.
This lifecycle approach promotes accountability and continuous improvement. For architects, it highlights the importance of designing spaces that allow adequate access for metering, testing, and maintenance, factors that directly contribute to long-term efficiency.
Technical priorities
Key to HNTAS compliance will be the management of heat losses and flow temperatures. Optimised pipe sizing, effective insulation, and low temperature operation will be fundamental. Architects can support this by:
- Providing well-planned plant rooms and service risers to accommodate insulation thicknesses.
- Designing layouts that minimise pipe runs between energy centres and dwellings.
- Ensuring access for inspection and retrofit where required.
These design considerations reduce operational costs and carbon emissions, aligning building performance with client sustainability objectives.
Component performance & assurance
Heat Interface Units (HIUs) play a pivotal role in the overall efficiency and comfort levels of a network. Their ability to control heat transfer between the primary system and individual homes directly affects compliance.
Under HNTAS, specifying components that have been independently tested and verified, such as HIUs that meet recognised performance benchmarks, will help designers and developers meet the scheme’s technical criteria. Independent validation provides the objective data needed to demonstrate system reliability and consumer protection, without relying on proprietary claims.
Bridging the heat network knowledge gap
For many professionals, HNTAS represents a learning curve. The scheme builds on existing best-practice frameworks such as CIBSE CP1 (2020), but it also introduces new compliance and reporting mechanisms. A coordinated, informed approach between disciplines will therefore be essential. The Building Engineering Services Association (BESA) has been appointed to develop and deliver HNTAS training courses.
Architects can prepare by enrolling in the BESA Training, engaging in technical CPD opportunities, collaborating with heat-network specialists, and ensuring their teams understand how layout and building fabric decisions influence network performance. A successful design process will now increasingly depend on the integration of thermal, mechanical, and architectural expertise.
HNTAS as a catalyst for better design
For forward looking practices, HNTAS should be seen as an opportunity rather than a constraint. The scheme supports broader design goals, where reducing operational carbon, improving occupant wellbeing, and ensuring long term building value are prioritised.
By embedding efficiency principles early, architects can help deliver developments that are not only compliant but also resilient and adaptable to future energy requirements. In mixed-use or regeneration projects, for instance, an efficient heat network design can underpin the sustainability of an entire masterplan, supporting shared energy resources and reducing peak demand pressures.
Conclusion
The Heat Network Technical Assurance Scheme marks a pivotal moment for the UK’s approach to heat decarbonisation. For architects, it signals a more active role in ensuring the success of low carbon energy systems.
DESNZ is currently working on the technical documentation, and scheme pilots started in summer 2025, with formal implementation anticipated in 2026. Once the framework is in place, Ofgem will assume regulatory oversight, monitoring compliance and ensuring accountability across the sector.
By engaging early, coordinating across disciplines, and prioritising performance in both design and delivery, architects can help ensure that future heat networks meet regulatory standards, support national carbon goals, and deliver lasting comfort and value for the people who live and work within them.
Josh Collins is heat networks manager at Altecnic Ltd