New Part L 2021: Government finally responds to Future Homes Standard Consultation

The government response to the Future Homes Standard was published in mid-January 2021, almost a year after the consultation closed. It should be reviewed in detail by developers to understand implications on new developments and those already under construction.  This article summarises six key points relating to the interim Part L which will be implemented while the government consults and develops further technical details on the Future Homes Standard to be introduced in 2025.  Additional information on Part F and the new Approved Document for Overheating will follow.

When will the new Part L come into effect? 

From June 2022.  Developers must submit a building notice/initial notice or deposit plans by June 2022 and commence work on each individual building under that notice by June 2023 for transitional arrangements to apply.  If work has not started on a building by this date, it will be subject to the new requirements, increasing the chances of multiple different versions of Part L being applied to a single site.

The response is not explicit on how this will affect sites already under construction with a building notice covering buildings where work will not commence prior to June 2023.

The Government will consult on the Future Homes Standard in the spring of 2023.

What level of uplift to the energy standards will be introduced in 2022?

The uplift will be equivalent to a 31% reduction in regulated CO­₂ emissions compared to a home built to meet Part L1A (2013).  Homes built to the new standard will be required to meet carbon, primary energy, affordability and fabric energy efficiency standards (the government had proposed removing the fabric standard in the consultation but has reintroduced it in this response).

A further consultation is now underway to determine the level of the Fabric Energy Efficiency Standard in the Future Buildings Standard consultation.

Can gas boilers still be used in new homes?

Yes, although our analysis suggests that it will be cheaper to install a heat pump in most cases due to the significantly higher fabric and services standards and onsite renewable energy generation required to achieve compliance where gas boilers are installed.  Direct electric heating will also struggle to meet the new standards without very significantly higher energy efficiency standards and onsite renewable energy generation.

Can gas CHP still be used to supply heat networks serving new homes?

Possibly.  Under the consultation versions of Part L and SAP, gas-CHP performed very poorly and it was unlikely that dwellings connecting to existing heat networks served by gas CHP would be capable of complying with the CO₂ or primary energy standards.

The government now intend to change the emissions and primary energy factor in SAP to reflect ‘the carbon emission reduction benefits of gas CHP’, but little detail is given in this response.  They will be carrying out a separate consultation to address this issue in early 2021.

Can Local Planning Authorities set higher standards for energy efficiency at a local level?

Yes. The government are not going to amend the Planning and Energy Act 2008 at this stage, but will review this position ahead of the implementation of the Future Homes Standard in 2025 based on responses to the recent planning white paper consultation.

Will all new dwellings be required to have air tightness tests carried out?

Yes. Although on many developments subject to additional planning energy targets already do this, it will become mandatory under the new Part L.  New CIBSE airtightness testing methodology and an optional Pulse testing alternative to the door blower method will be introduced to improve the accuracy of air pressure tests.