Part L - Conservation of fuel and power

Publication title: Approved Document L, Conservation of fuel and power, Volume 1: Dwellings, 2021 edition incorporating 2023 amendments 
Date published: December 2021
Last updated: 2 February 2023

Summary

Approved Document L Volume 1 applies to dwellings only and contains current and future guidance covering the energy efficiency requirements as set out in Part L of Schedule 1 to the Building Regulations and in a number of specific building regulations.

Approved Document L is split into two volumes; Volume 1 covers dwellings, Volume 2 covers buildings other than dwellings.

Guidance provided includes information about limiting heat gains and losses, air permeability and pressure testing, insulation regulations, boiler productivity, lighting, and storage techniques for hot water. Further information covered includes fixed standards for Carbon Index ratings, solar emissions, heating and ventilation systems, space heating controls and air conditioning systems, amongst other fuel and power systems. 

These documents are updated regularly due to improvements in technologies and materials available in the construction and modification of buildings, so please ensure you are reading the most up to date copy of the document. 

Download

The Merged Approved Documents¹

A consolidated version of the individual Approved Documents published by the government, now presented as a single, searchable PDF.

Non-consolidated version

Approved Document L, Conservation of fuel and power, Volume 1: Dwellings, 2021 edition incorporating 2023 amendments² 

Changes in this version

As of 15 June 2022, the guidance will change due to The Building Regulations etc. (Amendment) (England) Regulations 2021³ and the following two approved documents will be in force:

• Approved Document L, Conservation of fuel and power, Volume 1: Dwellings
• Approved Document L, Conservation of fuel and power, Volume 2: Buildings other than dwellings

These will replace the following four Approved Document L parts:

• Approved Document L1A, Conservation of fuel and power in new dwellings
• Approved Document L1B, Conservation of fuel and power in existing dwellings
• Approved Document L2A, Conservation of fuel and power in new buildings other than dwellings
• Approved Document L2B, Conservation of fuel and power in existing buildings other than dwellings

Previous versions

Previous versions of Approved Documents can be found in our archive list⁴.

1. https://www.gov.uk/guidance/building-regulations-and-approved-documents-index#approved-documents
2. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1133079/Approved_Document_L__Conservation_of_fuel_and_power__Volume_1_Dwellings__2021_edition_incorporating_2023_amendments.pdf
3. https://www.legislation.gov.uk/uksi/2021/1391/contents/made
4. https://www.planningportal.co.uk/applications/building-control-applications/building-control/approved-documents/part-l-conservation-of-fuel-and-power/previous-editions