Photographic evidence is now part of the BREL As-Built submission under Approved Document L 2021, in force since 15 June 2022.
The reason is straightforward. Before 2022, Part L compliance was based largely on paper. The drawings said one thing, the SAP modelled another, and what got built was often a third thing. The "performance gap" between modelled and measured energy use sat at 20–40% on a typical new build. The photographic evidence requirement closes that gap.
What the evidence has to prove
For every element listed in the Design Stage report, the photos taken on site have to demonstrate four things:
The product is the one specified. A label, badge or commissioning sheet showing the manufacturer, model, U-value or efficiency matches the design.
The product was installed continuously. Multiple shots across the dwelling showing the insulation, membrane or system isn't patchy or interrupted.
The detail was built correctly. Photos of the junction before it is covered — IWI return at a window reveal, perimeter strip at a floor edge, insulation overlap at the eaves.
The dwelling really is this one. Location-tagged and timestamped photos so each shot is verifiably from this site, taken at the right stage of construction.
Who checks the evidence
The Approved Inspector or Building Control body reviews the As-Built BREL submission, including the evidence pack, before issuing the Final Certificate. In practice, enforcement during the first wave (2022–2024) has been variable — some inspectors have still issued certificates without a complete pack — but the requirement itself is not optional. Treat it as mandatory on every project.
Why photos and not site inspection
In-person inspection of every new dwelling by a qualified surveyor would cost more than it saves. Photos work because:
Site teams already have phones — no new hardware.
Photos create a digital, dated, location-tagged audit trail.
Building Control can spot-check a percentage of projects rather than visit every site, because the evidence is consistent across the cohort.
AutoBREL's job is to make that capture process structured rather than ad-hoc. The separate article What photographic evidence is needed walks through exactly what to capture for each element.
Tags: evidence, why, regulations.