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Changes to Part L and Part F of the Building Regulations

This consultation set out the Government plans for the Future Homes Standard to be introduced by 2025. It is the first stage of a two-part consultation about proposed changes to the Building Regulations.

Objectives of the consultation

The UK has set in law a target to bring all its greenhouse gas emissions to net zero by 2050. As part of the journey to 2050 the Government committed to introducing the Future Homes Standard in 2025 and an uplift to energy efficiency standards and requirements in 2020 as a stepping stone to the Future Homes Standard. They expect that an average home will have 75- 80% less carbon emissions than one built to current energy efficiency requirements.

The consultation included proposals for revising the Approved Documents for Part L and F to make them easier to navigate and to support efforts to simplify Approved Documents more generally. It set out proposal for changes to transitional arrangements to encourage quicker implementation of the new energy efficiency requirements and also proposed to remove the ability of local planning authorities to set higher energy efficiency standards than those in the Building Regulations.

This consultation closed on 7 February 2020.

Supporting papers

To download documents which supported this consultation, follow the links below.

CIBSE response

CIBSE very much agree with the stated overall ambition described in the Consultation Document, but have strong concerns that the proposals set out are not sufficiently ambitious to deliver significant progress towards meeting the objectives of reducing carbon emissions, annual energy consumption and peak demand, and ensuring affordability to consumers. The proposals for Part L 2020 do not represent the required “meaningful and achievable step” towards zero carbon, and the timeline and content of the Future Homes Standard is not ambitious enough, nor does it begin to address real in-use energy performance and carbon emissions.

In summary, we recommend the following:

  • Tighten requirements on the performance of buildings themselves (independently from grid decarbonisation) to deliver additional savings in carbon emissions, reduce annual energy consumption and peak demand, and keep heating costs lower.
  • Review the notional building, which is currently proposed to have a gas boiler: instead, the notional building should encourage the transition to low-carbon heating and strongly discourage all-electric buildings with poor fabric performance. It should have excellent fabric efficiency and a low carbon source of heating.
  • Ensure that the proposals overall strongly encourage a fabric first approach: currently, the proposals for removing the FEES, combined with a gas-heated notional building and a lower grid carbon factor, mean that a 2020 Part L compliant building could have worse fabric performance than one complying with 2013 Part L. This is clearly very much in the wrong direction in terms of reducing energy consumption and peak demand, and also causes fuel poverty concerns.
  • Assess heat networks on a fair basis: the current proposed “technology factor” for schemes connected to heat networks would provide an excessive (45%!) allowance for additional heating emissions. While we understand heat networks may benefit certain situations, this should not be at the expense of increasing emissions for new development. Fudge factors which distort the assessment of building performance and do not treat technologies equitably are unfair and must be avoided.
  • Review performance metrics: the proposals currently include 2 «system» metrics (carbon, and primary energy), which do not help connecting consumers with actual building performance and do not encourage building performance directly enough, as they are heavily dependent on the wider system. We understand this is considered necessary for the implementation of the Energy Performance of Buildings Directive (EPBD), but we strongly encourage other metrics to be considered e.g. retaining FEES (or other similar heating demand metric).
  • Commit to developing the Future Homes Standard (FHS) in 2020: the current consultation proposes what the FHS should require for fabric, which should allow MHCLG to release the FHS well before 2025, much earlier than proposed. Early certainty about the content and implementation of the FHS will drive market leaders to adopt it early; in addition, government should consider ways to incentivise early adoption.
  • Within the FHS, state a clear trajectory towards operational requirements covering all energy uses and create the necessary legislative framework accordingly. The evidence that this is required is compelling, as the current approach is not delivering the required step changes in energy consumption.
  • Create the legislative framework allowing the introduction of a requirement for disclosure of operational performance. While we acknowledge the required legislative work may now be difficult to complete on time for the introduction of Part L 2020, we recommend that government should publish a statement of intent by the time Part L 2020 is introduced, and prepare the legislative framework to be ready by 2023 at the very latest.
  • Retain the powers for local authorities to set requirements beyond minimum building regulations requirements (subject to the usual viability testing of their local plans and planning applications). Again, this is a crucial part of helping to develop supply chains and expertise, benefiting the whole market. There is evidence from local authorities that preventing this would increase carbon emissions, compared to their current (already tested) plans.
  • Part L and Part F are inextricably linked, particularly as we move towards very low energy buildings. We have indicated in our responses the key links between these documents. This means that government needs to show the direction of travel on Part F, whether in the FHS or in Part F: it needs to be clear that low energy and low carbon buildings will mean exemplar airtightness and appropriate ventilation to deliver good indoor air quality.
  • In order to truly prepare for a net zero carbon UK in a changing climate, the FHS should also include consideration of other elements, including: peak demand (this should at the very least be estimated and reported on), embodied carbon of key building elements (data should be gathered by MHCLG for the purpose of benchmarking and future standard setting), and adaptation and resilience to climate change (including overheating, water consumption, flooding, and drainage).

We have provided a substantial amount of supporting information to illustrate and justify our comments, and point at possible solutions. We would be very happy to discuss this with MHCLG and to review options for revised proposals and the development of the FHS.

To read the full CIBSE response, follow the link below.