Part L: Why the delay?

It may feel like we’ve written a novel’s worth of articles talking about the new Part L… and we probably have. We’ve been waiting more than three years for the Government to make an announcement and it’s been a turbulent few years for UK politics. But we’re now hoping we see light at the end of the tunnel.

To save you reading back through the Energist archives, here’s a summary of what’s happened so far:

2016 was earmarked as a momentous year for going green.

This was to be the year all new dwellings would be zero carbon. We were not surprised to learn that this goal was going to be missed. We were surprised that the zero carbon homes policy had been completely scrapped rather than just delayed.

We did see one noticeable release in 2016 – a new SAP methodology. Traditionally, a new SAP manual is the aperitif to a new set of building regulations, so we were expecting a new Part L to follow soon after.

Then, we had Grenfell.

Any work on new Building Regulations was suspended while Dame Judith Hackitt reviewed the suitability of our current documents. Nearly a year later and the publication of the Hackitt Review did not make for easy reading.

Despite this, the Government announced it would accept and take on board every recommendation in the Review. The most urgent points (concerning Part B and fire safety) would be addressed as the priority, and other recommendations would be mulled over in Spring 2019.

One could assume this date was chosen so the Government could focus on getting Brexit in the can before tackling the rest of the Hackitt Review. As we know, this bit hasn’t gone to plan.

Being in Brexit limbo makes writing new laws trickier than normal.

Part L is a perfect example of why:

Energy Performance Certificates (EPC), High Efficiency Alternative System reviews (HEAS) and Nearly Zero Energy Buildings are all EU directives. The Government has previously announced they plan to keep EPCs for the foreseeable future, but do we want to keep other EU-led requirements in our regulations if they’re not going to be enforced post-Brexit?

While these riddles continue to echo their way around Westminster, another new SAP methodology was released last summer. Given the previous version was never adopted by any of the UK Governments, we are hopeful SAP 10 (to give it it’s proper title) is a signal that regulation changes are on the way.

Although we don’t yet know what a new Part L might entail, the SAP document gives us some clues about the impact on future dwelling designs.

The biggest impact will surely be the decarbonisation of the National Grid. Since Part L was last updated the carbon intensity of electricity has more than halved. Swapping coal power stations for wind farms has made a substantial difference to the UK’s energy supply, which means Dwelling Emission Rates will certainly be lower under SAP 10. Whether this means electric heating systems will be easier to pass is still unknown, as the new targets are still to be confirmed.

On the flip side, dwellings with district heating networks are likely to see their emission rates increase. Heat losses from these systems is going up, and the carbon offset gained through Combined Heat and Power networks is going to have far less of an impact.

There are still a few weeks remaining before the end of Spring 2019, and we are staying hopeful that some form of announcement will be made concerning a change to Building Regulations.

By the time we’ve gone through the usual evidence gathering and consultation stages it’s unlikely a new Part L will go live until late 2020 at the earliest. We’ll publish the news as it unfolds, so stay with Energist to keep up to date with the latest announcements on SAP and Part L.

Further reading:

• The London Plan adopts SAP 10 emission factors
• Hackitt review and Government response
• What will SAP 10 mean for you?