TradeStampAlways follow your scheme provider’s latest guidance.
This page sums up public guidance as of October 2026. Requirements change, and your provider or retrofit coordinator may ask for more.
Why photo evidence matters
TrustMark’s quality assurance covers government-funded work that must be lodged in the TrustMark Data Warehouse, including ECO, the Great British Insulation Scheme and the Warm Homes Plan. Salix Finance, a government-owned body that administers several retrofit funds, says plainly that “photographic evidence is a requirement for TrustMark lodgement.”
Salix also warns that return visits raise the risk you can’t get back into the home. Getting the photos right first time saves time and money.
What the guidance says
Geotag, date, time and location on every photo
Salix’s tips for TrustMark photo evidence say:
“All photos must be geotagged and include the date, time and location.”
It adds that geotagging and timestamp camera apps “can help to save time and meet requirements”. Photos should be clear, well lit, free from tools, hands or people, and in landscape where possible. Label each file clearly, for example ASHP_mid_install_pipework.jpg.
Mid-installation and post-installation
Salix lists two stages: mid-installation, “to show the work being done (e.g. insulation before boarding)”, and post-installation, to show the final result, “labels and any controls or meters”.
Evidence for the retrofit coordinator
For PAS 2035:2023 projects, TrustMark’s site visit requirements say photo or video evidence of the progress and quality of the installation must be recorded. As a minimum, it should include:
- Images specific to the measure, in line with the relevant PAS 2030 annex or MCS standard
- Ventilation in place at the time of the visit
- How measures meet, where there’s more than one
- Any significant building detail, areas of concern and anything that doesn’t match the design
A site visit is mandatory for external, internal, room-in-roof, underfloor, park home and flat roof insulation. TrustMark can withdraw the option to use digital evidence if it finds evidence missing, incomplete or unsuitable.
If an audit finds a problem
TrustMark’s Remediation Evidence Guide says new photos must mirror the original, “taken from the same angle and location wherever possible”, close enough to show the fix, and in good light. “Blurred, dark, or obscured photographs will not be accepted.” Since 13 July 2026, TrustMark also requires a video walkaround after on-site remediation, where an audit found open non-compliance.
Photo checklist for every job
- Location services on, and your phone’s date and time set automatically
- Before you start (good practice): the front of the property and the areas you’ll work on
- Mid-installation: the work before it’s covered, such as insulation before boarding
- Post-installation: the finished measure, labels, serial numbers, controls and meters
- Ventilation, inside and outside
- Wide shots for context, plus close-ups of junctions, edges and seals
- Landscape, well lit, in focus, nothing in the way, plus a few extra angles
- Every photo checked on site before you leave
- File names that say what each photo shows
- Photos moved to your company’s secure system, not left on a personal phone
What to capture, by measure
A summary of Salix’s tips. See the full list for other measures.
| Measure | Mid-install | Post-install |
|---|---|---|
| Cavity wall | Open drill pattern | Ventilation inside and out, thermal bridging addressed, all walls treated |
| External wall | Junctions around windows and key areas | Full coverage, ventilation, edges, seals and finishes |
| Internal wall | Insulation and vapour control layers | Ventilation, thermal bridging measures, final finish |
| Loft | Not required | Full coverage, insulation depth, insulated loft hatch, ventilation |
| Room-in-roof | Work in progress | All key roof elements, difficult areas, ventilation |
| Air source heat pump | Pipework, radiator fitting | Unit with serial badge, cylinder, controls, labels and model numbers |
“Geotagged” or “stamped”? Ask what your provider checks
- Geotagged usually means the location is saved inside the photo file as hidden data (metadata). You can’t see it on the image.
- Stamped means the date, time and location are printed on the image itself, so anyone can see them, even on a printout.
To be clear about our own app: TradeStamp stamps the date, time, street address and GPS coordinates onto each photo and lists them in its PDF report, with map links. It does not save the location as metadata inside the photo file. If your provider checks metadata geotags, confirm with them before you rely on a stamp alone.
TradeStamp’s Before, During and After tags line up with pre-, mid- and post-installation photos, and reports can be set to A4.
Keep photos safe and lawful
Photos taken in someone’s home are personal data, so UK GDPR applies. TrustMark’s draft guidance on photos and video walkarounds (July 2026) says to:
- Tell the homeowner why you’re taking photos, and get consent before recording inside
- Only photograph what you need to evidence the work
- Check each photo for reflections and personal items before you save or upload it
- Store photos in a secure, access-controlled system, and not leave them “on a personal camera roll or personal cloud photo storage”
TradeStamp keeps photos inside the app on your phone and never uploads them. Once the job is done, move them to your company’s secure system.
Date, time and location on every photo
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