Climate change is causing another change – in building regulations

Climate change is causing another change – in building regulations

Climate change and an increase in extreme weather events has caused the UK government to update building regulations, as part of their wider commitment to achieving net zero by 2050.

The changes to regulations have been designed to provide a foundation for more energy efficient homes, with improved ventilation and protection from overheating.

Here is everything you need to know about changes to Part L and Part F of the Building Regulations, the Future Homes Standard and the Future Buildings Standard.

What are we responding to?

When it comes to man-made climate change, few sceptics remain. This means two things:

• We have to cause less climate change in the future
• We have to deal with the effects of the climate change that has already happened

In 2015, the UK signed up to the Paris Agreement on climate change and also the UN’s 2030 Agenda for Sustainable Development, including commitments to climate action. In 2019, the government went further, pledging to reach net zero greenhouse emissions by 2050. Since 40% of CO2 emissions come from building operations and construction, these goals are unattainable without a central focus on reducing the carbon footprint of buildings.

On the topic of existing climate change, the Met Office, among other sources, discusses the steady rise in intense storms, floods, and periods of extreme heat and drought. As the Royal Institution of Chartered Surveyors notes, “the UK has experienced more extreme weather events in recent years, and these have damaged buildings and infrastructure. More frequent and intense winter storms have caused strong winds and heavy rain, resulting in both structural damage and flooding.”

Dealing with existing climate change

Because buildings can be expected to see more wind load over their lives, the regulation in this area has changed, with BS EN 1991-1-4 replacing BS 6399-2.

Part F of the Building Regulations, which covers ventilation, has also been updated, and there is a new document, Document O, which sets out what construction firms must do to mitigate overheating in new buildings.

In other areas, however, there is no regulatory change. Flood events have been increasing steadily in the UK, and are expected to rise further, but almost no mention of floods exists in the Building Regulations.

Causing less climate change

Two public consultations were held recently, in connection with the UK’s goal of reaching net zero emissions by 2050. The first was called The Future Homes Standard and explored proposed regulatory changes for the construction of dwellings. The second, The Future Buildings Standard, focussed on other structures.

Some aspects of the new standards have been established, but further consultations will occur in 2023, before implementation in 2025. However, the government has already made changes to the Building Regulations – changes that can be considered an interim step towards the 2025 full implementation. These changes came into effect in June 2022, although projects that were already underway can, in some cases, proceed under the old rules. Specifically, the old regime can be followed if two boxes are ticked:

• Building notice, initial notice, or full plans for building work were submitted to a local authority before 15 June 2022
• Work commences by 15 June 2023

Note that if you are developing several plots on the same site, you must start construction on the particular building by the date above, to qualify for this transitional provision use of the old regulations. What you must start by June 2023 is “substantial” work – excavation for strip or trench foundations or for pad footings, or digging out and preparation of ground for raft foundations, for example.

As discussed above, if you are working under the new regulations, there are revisions to the rules governing ventilation, and new requirements regarding overheating. In addition, substantial changes have been made to Part L of the Building Regulations. Part L governs the conservation of fuel and power, setting standards for the energy performance of buildings. Two documents exist, one for dwellings and one for other buildings. Note that Document L says that a dwelling is “a self-contained unit designed to accommodate a single household…Buildings exclusively containing rooms for residential purposes, such as nursing homes, student accommodation and similar, are not dwellings”.

The aim of these new rules is to reduce CO2 emissions from new build by 30% (homes) or 27% (other buildings). The standards introduced in 2025 will improve that reduction to 75-80%.

Do the changes go far enough?

Despite the reduction in carbon emissions, not all sources agree that the changes are sufficient. “While a 75-80% reduction in carbon emissions is welcome, we’d like to see government implement specific targets for carbon emissions, rather than continuing to compare emissions from existing buildings”, comments the website architecture.com. “Disappointingly – and quite significantly – the government has made no commitment calculating the operational energy or embodied carbon of new homes.”

From an operational perspective, however, even the implemented changes are significant. If you would like us to help guide you through this evolving regulatory landscape, please get in touch via our contact page.