Toby Howard-Willis, Technical Sales Engineer for RWC, has created this guide to outline the key regulations that are shaping 2026 and explain what they mean for installers.
2026 is a milestone year for the plumbing and heating industry, due largely to the rapid shift towards decarbonisation, smart technology, and strict sustainability regulations, all of which are driven by the UK’s Net Zero targets.
This year brings into effect a series of evolving standards that place greater emphasis on system efficiency, installer competence and long-term performance. And with these standards come greater expectations on installers to demonstrate not only technical ability, but also a deeper understanding of how components, controls and system design interact.
Low-carbon heating in newbuilds
The push towards higher energy efficiency performance continues into 2026, with the updated Part L and Part F of the Building Regulations introduced in 2025 now fully embedded across residential and commercial projects. Together, they are reshaping how heating, hot water and plumbing systems must be designed, installed and commissioned, particularly in increasingly airtight and energy-efficient buildings.
With an objective to dramatically reduce carbon emissions while improving both energy and water efficiency, the target is clear: new homes should produce 75-80% lower carbon emissions than properties built to 2013 regulations. To achieve this, the updated regulations call for a more rigorous, system-wide approach to energy efficiency and mandate that homes are designed around low-carbon heating solutions from the outset.
Expected in 2028, the Future Homes Standard represents a major change in the construction of new homes. With gas boilers banned from new build homes, as part of the government’s commitment to reducing carbon emissions by Net Zero 2050, low-carbon heating is becoming the default and alternatives such as heat pumps and heat networks will become the new standard. This move from traditional fossil fuels will improve overall energy and water efficiency for homeowners by installing hot water systems designed for efficiency, safety and future adaptability. The Future Homes Standard, therefore, shifts the installer’s role from replacement work to using trusted, compliant components that help ensure installations are ready for long-term, regulatory expectations.
Likewise, the Part L and Part F regulations remove straightforward like-for-like replacements and introduce stricter performance targets for boilers, heat pumps and heat interface units, requiring whole-house energy performance to be considered. Products must be suitable for low-temperature, high-efficiency operation, and installers will increasingly be assessed on the overall performance of a system. This includes the delivery of low-temperature heating and the provision of appropriate ventilation strategies within airtight properties.
Together, Part L, Part F and the forthcoming Future Homes Standard are redefining best practice. It is therefore advised that the installers adopt a whole-house perspective and prioritise measurable outcomes at every stage, to be in the best position to meet regulatory expectations in 2026 and beyond.
Heat networks enter a new era
Heat network regulations have been in force since 2014, but January this year marked a significant shift in oversight, with Ofgem becoming the statutory regulator for heat networks. While the regulations themselves aren’t new, the transition brings all heat networks into a fully regulated status that sits under a broader regulatory framework. With this, new standards are introduced: expanded consumer protections, formal licensing requirements, higher technical standards, and strengthened reporting and enforcement powers.
Greater regulatory scrutiny from Ofgem also means that incorrect metering or substandard installations can now lead directly to non-compliance and potentially costly corrective action. As a result, the correct installation of meters, valves and heat interface units is no longer simply a matter of best practice; it is fundamental to regulatory compliance. Valve selection, flow control and overall installation quality all play a direct role in ensuring that heat is delivered efficiently, and that metering remains precise and reliable.
There are a variety of components that installers can utilise to help them meet regulatory requirements. Firstly, Pressure Reducing Valves (PRVs) from Reliance Valves, are important within heat networks as stable system pressure is essential for accurate metering and consistent operation. By maintaining controlled downstream pressure, PRVs help prevent excess flow rates and offer a level of stability that not only protects equipment and components but also supports billing accuracy and overall system efficiency.
Secondly, high-quality push-fit connectors and twist-and-lock fittings supplied by John Guest are well suited to the demands of communal and district heating systems, where durability and long-term integrity are critical. When combined with careful pipework design and proper commissioning, these components help ensure that communal heating systems remain efficient and compliant. Thirdly, the Tenant Valve Advance combines the functionality of a water meter carrier port for usage monitoring or billing. A one-piece combination, it controls water pressure and monitors usage and supply across multi-occupancy buildings.
With Ofgem now in place, compliance is closely linked to performance, transparency and accountability. For installers, this means technical understanding, careful product selection and precision installation are more crucial than ever in ensuring that heat networks meet the standards expected under the new framework.
Increased scrutiny on RPZ compliance
This year sees a heightened focus within the Water Supply Regulations, for the most part, in relation to the installation, testing and ongoing maintenance of Reduced Pressure Zone (RPZ) valves. While RPZ backflow protection is not a new practice, the enforcement and oversight of it has increased significantly and placed greater responsibility on the installers carrying out the work.
The revised Approved Installation Method for RPZ backflow valves came into force in early 2025. It introduced updated technical expectations and mandates that testers are required to have compliant, updated test equipment in place by the 30 June 2026. While the principles of correct installation and annual testing remain familiar, this formal equipment deadline represents a new requirement that installers and testers must plan for to avoid falling foul of compliance rules.
As well as the requirement for compliant equipment, there is the broader move towards demonstrable competence, documented procedures and auditable compliance. Water companies are now placing stronger emphasis on formal competence and certification for RPZ testers and for installers this means that incorrect installation, or inadequate testing, can result in enforcement action, mandatory retesting or even system shutdowns.
Backflow protection is under particular scrutiny in commercial, mixed-use and higher-risk domestic settings, where the potential consequences for contamination are greater. As a result, the use of WRAS-approved products is fundamental. Reliance Valves offers dedicated backflow prevention valves designed to meet regulatory requirements, alongside isolating valves that support safe servicing and maintenance. Here, high-quality push-fit connectors can also help reduce the risk of installation errors and minimise the likelihood of corrective work.
Overall, backflow prevention can no longer be treated as a “fit and forget” activity. Rather, it demands compliant products, correct installation practices, certified testing and ongoing maintenance. As enforcement tightens, installers who prioritise competence, documentation and product compliance will be best positioned to meet the evolving demands of water supply regulation.
Choosing the right components
Meeting these regulations, as they come into force throughout the year, relies on choosing components that support efficiency, safety, and compliance across the whole system. It also means that valves, fittings and controls are no longer secondary; in fact, they are central to meeting modern building and water regulations, which is why installers must align the regulatory requirements with the demands of everyday usage.
Reliance Valves and John Guest, both part of the RWC family of brands, manufacture market-leading plumbing and heating solutions that support installers to get every project right. In practice, with effective product selection from trusted manufacturers, installers can shape homes for the future.
For more information, visit: www.reliancevalves.com/gb/en
