Colin Timmins, H&V Portfolio Manager at BEAMA, addresses incoming requirements for TRV installations on boiler replacements.

The recent consultations on Part L of the Building Regulations for existing homes in both England and Wales propose a small but significant step forward in addressing one of the areas that can be reasonably described as low hanging fruit for better levels of energy efficiency in our homes. 

That change will make it a requirement for individual room temperature controls such as thermostatic radiator valves (TRVs) to be installed when replacing a boiler. 
It is one of the longstanding gaps in Part L, which deals with energy conservation, that the addition of TRVs when a boiler is replaced only appeared in the Domestic Building Services Compliance Guide as a ‘good practice’ recommendation. 

This is despite the fact that TRVs are a proven energy saving measure and highly cost-effective when done while the heating system is already drained down. What’s worse is that this was actually a step backwards from the 2006 regulations when systems were required to be zoned, and installing TRVs in bedrooms was a common means of compliance. 

This time round, the new version of Part L for both England and Wales proposes that a requirement for “self-regulating devices”, such as TRVs, for new systems and with boiler replacement, will be introduced as a new regulation rather than being part of guidance. 

This will actually make it a cornerstone of compliance as they will be a clear legal requirement, not just listed as something that ‘should’ be done. Of course, there are situations where such an addition to an existing system may not be technically or economically feasible but, as the Welsh regulations bluntly state, “in normal circumstances, the installation of thermostatic radiator valves in wet central heating systems is likely to be economic feasible”.

Other ways of complying are also possible, such as room thermostats in each room, which is usual with underfloor heating systems for example, but it is likely that in most cases fitting TRVs to existing radiators will be the route to comply. The terminology used in the new regulations of “self-regulating devices” has not been commonly used before and actually came about as part of negotiations in the European Union for the Energy Performance of Buildings Directive, which was revised in 2018. 

Several years before this, BEAMA and its European counterpart eu.bac had identified that regulations to drive the installation of individual temperature controls were piecemeal across Europe, despite it being an established energy saving technology that had actually been compulsory in German homes since the 70s. 

BEAMA worked on the development of a white paper explaining the benefits of such a no-regrets policy action to both the environment and consumers, as well as carrying out research and analysis to show the scale of the savings potential – both financial and in terms of carbon emissions. Ultimately these documents persuaded policy makers across Europe to address this largely missed opportunity. 

It is to the UK’s credit that, despite leaving the EU, the government has committed to implement what it previously agreed in the EPBD revision. That said, it would be hard to argue that we are working towards ‘world-leading’ environmental standards if we fell behind the rest of the EU in requirements for individual room temperature controls, which are such a simple but fundamental energy saving measure.

The new versions of Part L of the Building Regulations are due to come into force in England and Wales early in 2022. Details for Scotland and Northern Ireland are yet to be determined, but it is expected that they will follow suit in this respect. 

The new regulations will be a boost to the many installers who have long considered the addition of TRVs at the time of boiler replacement to be an essential factor in providing customers with an efficient system, but have been at risk of being undercut by others content to deliver minimum standards only. At last there will be a level playing field in this respect.

A willingness to aim for best practice will still be desirable. One of the common reasons why adding TRVs to an existing system may not prove to be practical is a lack of compatibility with older radiator fittings, or simply the condition of those radiators. 

In such cases, the renewal of such radiators will benefit customers, both by facilitating the fitting of a TRV and also by removing a radiator that is likely to have poor performance compared to newer emitters, particularly if it has a build-up of sludge that has developed over time and will impact on its operation. 

As outlined at the start, this regulatory change is a small step but a very important one that will benefit householders and move us forward on the path to having more sustainable homes.