Photographic Evidence in Appendix B of Approved Document L Volume 1: Dwellings

2021 edition – for use in England

18 April 2023

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Approved Document Part L Volume 1: Dwellings has introduced the requirement for photographic evidence to be provided in order to address the gap between what has been agreed in relation to a building’s energy performance as designed and what is handed over to the customer (the performance gap).

There is also a requirement for a BREL report to be provided at both design and as-built stage, again with the aim of closing the performance gap. This article will focus on the photographic evidence and review how the images will be collated and to whom they should be provided.

Design Stage

The required photographs are listed in Appendix B of Approved Document L the list is not complete and different dwelling types may have differing requirements. The photographs can be taken by anyone, but do need to be of sufficient quality and high enough resolution to allow for a qualitative audit, the images should also be time stamped and geo-tagged to ensure they relate to the building being reviewed. The photographs should show continuity and type of insulation, detailing in relation to thermal bridging and airtightness, insulation of pipes/ducts where required and the installed building services.

The photographs required for each dwelling should be agreed prior to construction work starting, this may be done alongside the OCDEA (on construction domestic energy assessor), designer and/or builder. As noted the images can be taken by anyone and it is important that the duty is embedded in that person’s role on site, other site roles need to be made aware of these requirements in order to ensure pictures are taken before being concealed by follow on trades.


During Construction

Once a photograph has been taken on site this needs to be forwarded to the OCDEA for review, and consideration. The assessor is governed by a set of conventions which will determine the level to which they review the image, what actions they need to take and the consequence of the non-provision of images during construction (this may include elements of construction subject to off-site manufacture). In instances where the photo shows a change to a detail, for example the ground floor insulation, the assessor will need to review the SAP Calculations and update the Part L compliance metrics, depending on the outcome of this review further changes may be required elsewhere to ensure continued compliance with Part L.

Additional close up photographs may be needed where a long shot image provides insufficient detail.

You need to…

  • familiarise yourself with the photographic evidence required (Approved Document L Appendix B)
  • consult with your energy assessor to agree required images for each plot
  • train site staff in the requirements of photographic evidence.


On completion the OCDEA should be in possession of a full suite of photographs at which point they will also look to conclude the As-Built BREL and the EPC for the dwelling. It is expected that at this point the building control body will be provided with the EPC, BREL and Photographs as evidence that the building complies with the energy efficiency requirements of Part L.

The EPC, BREL and photographs should also be provided to the building owner during the handover.

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