Wales published changes to Part L in May 2022, the UK government's Building for 2050 research report states1. Part L is the Building Regulation that sets the standard for the energy performance of new and existing buildings1. The report, published by the then Department for Business, Energy & Industrial Strategy and updated on 5 December 2022, records the Welsh publication alongside the English timetable1.
The same report says that in December 2021 the UK government published the Part L 2021 standard as a stepping stone to the Future Homes Standard1. It adds that the government has consulted on a Future Homes Standard for England, to be brought into force in 20251. The standard, as described in the report, will ensure that new build homes are future-proofed with low carbon heating and high levels of energy efficiency, with 75% to 80% lower emissions than those built to current Building Regulations standards1.
The report does not set out the content of the Welsh changes, the standards they introduce, or the dates they took effect. Those details have not been reported in this document1. The document is a research report rather than a regulatory impact assessment, and it gives no figures for costs to households or builders in Wales1.
The wider research project ran for five years, begun in 2017 and completed in 2022, and investigated low carbon housing through four in-depth case studies of schemes across England and Wales1. It notes that homes, both new and existing, account for 17% of greenhouse gas emissions in the UK, against the government's commitment to achieve net zero greenhouse gas emissions across the UK by 20501. The Climate Change Act commits the UK government by law to reducing greenhouse gas emissions by at least 100% of 1990 levels, net zero, by 20501.
"Wales published changes to Part L in May 2022"
Why it matters for households
Part L governs the energy performance of a home, so changes to it shape how much energy a new or altered dwelling is expected to need for heating, hot water and lighting1. For a household in Wales, the practical effect runs through the standard a builder must meet rather than through anything the occupant buys or installs. Because Wales sets its own building rules in devolved areas, the Welsh timetable can diverge from England's, and the report records that divergence without describing it1. The report's framing is that building to a low carbon standard now avoids the need to retrofit those homes before the 2050 net zero deadline1. That matters for energy independence at the level of the individual home: a dwelling built to a tighter fabric and low carbon heating standard is less exposed to the cost of the fuel it burns and to later remedial work. The report also notes that no major housebuilder was building low carbon homes at scale at the time of the research, with the case studies drawn from small and medium-sized developers1.
What happens next
The report states that the government has consulted on a Future Homes Standard for England, to be brought into force in 20251. No next steps for the Welsh changes are given in the document1.