Part L is a ripple – don’t miss the sea change

Neil Hargreaves is managing director of Knauf Insulation

It is simultaneously the biggest change to building energy efficiency standards in a generation and a mere stepping-stone towards bigger change to come. But, while construction in England and Wales focuses on the details of the new Building Regulations England Part L (BREL), it is important that we don’t miss the wider context.

A more substantive shift is under way that will fundamentally transform the way we design and build in this country, and our industry needs to get ahead of it.

What’s new?

First, the headlines on BREL. It mandates a 31 per cent reduction in new-home carbon emissions (with a similar target of 27 per cent for non-domestic buildings). Fabric efficiency standards are higher, with a new Primary Energy metric to ensure a fabric-first approach is maintained, even as energy sources are decarbonised.

And it is all happening at a much faster pace, with the new regime already in place for new applications. It applies to all building work starting after June 2023.

But, arguably, the most significant change in the new regulations is the beefing up of testing and quality assurance. Every single home must now be tested for airtightness, as a sample is no longer acceptable, and a new BREL report is required that includes photographic evidence of installation quality.

Real performance

For the first time, the construction industry faces scrutiny of ‘as-built’ fabric quality at scale. And, while these are small waves, they are indicative of a sea change across multiple policy areas – one that can be summed up in two words: real performance. It’s time for buildings to deliver their promised performance in the real world.

The arguments for real performance in terms of energy efficiency are compelling. It is critical if we’re to hit the nation’s net-zero goals – climate crisis does not respond to theoretical efficiency. Today’s energy security and cost-of-living concerns make the need even more acute. And, frankly, it’s the right thing to do, for construction to deliver on the promises it makes, and for clients and homeowners to get what they pay for.

“All of this means that the industry must start preparing to deliver genuinely efficient buildings that stand up to scrutiny”

That’s why regulation is moving. The government’s EPC Action Plan is a statement of intent (EPCs must move from a reflection of the features of a building to the true measure of in-use building performance), enabled by innovative technologies that can measure fabric efficiency at scale.

Obligations for more widespread as-built performance measurement will be baked into 2025’s Future Homes Standard, with the Social Housing Decarbonisation Fund acting as a test bed for the approach in retrofit applications.

Enforcement will be courtesy of the New Homes Ombudsman, which has energy efficiency in its remit, and the power to enforce redress and issue fines of up to £50,000 per home where performance falls short.

All of this means that the industry must start preparing to deliver genuinely efficient buildings that stand up to scrutiny. But energy use is not the only aspect of building performance under the microscope.

Fire safety

Consider fire safety, and the ongoing ripples from the Grenfell Inquiry and Hackitt Review. National regulations have already changed, with combustible materials banned on the external walls of high-rise dwellings and some local planning standards going even further. Even where regulation falls short, pressure from insurers, mortgage providers and occupiers has kept the spotlight firmly on fabric fire safety.

Now the new Building Safety Bill will turbocharge accountability for safety across the construction supply chain. As the impact of noise on health becomes clearer, I anticipate seeing a similar shift in market attitudes to acoustic performance.

These are different issues, but at their heart is the same question: are buildings performing as people need them to? Compromises are no longer acceptable. Construction must be ready with answers.

Get ahead

My message to industry colleagues is this: see Part L for the opportunity it is. There’s no need to panic. Its requirements are easily met with existing products and solutions today.

It is a chance to get ahead of the sea change to come and a reminder that scrutiny is here to stay. All of us – manufacturers, specifiers, contractors and clients – have a role to play in delivering higher standards. We have just enough time to test and adopt the new processes, practices and products that will be required.

Let’s ride the wave, instead of being swamped by it, and deliver the genuinely efficient, safe, quiet and comfortable buildings the world needs – and the nation now demands.