What to photograph before building services are concealed
A field protocol for ducts, cable trays, wiring, pipes, wall chases, risers, penetrations and seals before suspended ceilings, boards, finishes or screeds hide them. The aim is not to collect more images, but to make hidden work findable and understandable later.
1. Plan the hold points before opening the camera
Use the programme and look-ahead plan to identify every area that will lose visibility: suspended ceilings, dry lining, chases, risers, raised floors, screeds and penetrations. Assign an owner and a check before each close-up milestone.
In chases and linings: conduits, boxes, water pipes, drains, insulation, backing and changes of direction.
In risers: floor-to-floor routes, brackets, joints, valves, manifolds, slab penetrations and access panels.
Below floors or screeds: conduits, underfloor heating, drainage points, joints and offsets from fixed references.
Through walls and slabs: cables, pipes, ducts, sleeves, edge protection and seals.
3. Ceiling voids: follow each service instead of photographing a tangle
Start from a doorway, column, façade, grid line or other fixed reference. Then follow each duct, tray or pipe in recognisable sections with overlap between frames. Include the ceiling grid whenever it helps relate the service to future access panels.
AI-generated editorial image illustrating the correct moment: services remain visible, ceiling references are present and the capture is made from a safe position.
Room overview with walls, openings and part of the ceiling grid.
Overlapping route views for ducts, trays and pipes.
Congested interfaces between structure, HVAC, electrical, fire and plumbing systems.
Dampers, valves, junction boxes and maintainable items that require access.
Supports, hangers, insulation, flexible joints, falls and terminal connections.
Safety: do not improvise access for a better angle. Use the planned access equipment and site procedure for any work at height.
4. Wall chases and dry lining: record the complete route
A close-up of one box does not explain where its conduits run. Capture the whole wall first, then each section, including corners, room transitions and the connection between chase, lining void and ceiling.
AI-generated editorial image. A scale can support a detail view, but the frame should retain enough wall and fixed openings to locate the work.
Photograph each complete wall before plastering or fixing the second board face.
Include boxes, conduits, pipes, manifolds, supports, backing and unfinished ends.
Record bends, groups, separation and crossings between systems.
If a dimension matters, take one view with a scale and another unobstructed view.
After a repair, repeat the image so the latest record shows the current condition.
For electrical work, photographs help recover the route but do not establish safety. The UK Approved Document P distinguishes design, installation, inspection, testing and information handover.
5. Risers, penetrations and firestopping: capture before and after
Relate the passing service, the wall or slab, the opening and the completed seal. Photograph the opening and services before sealing, then repeat the same viewpoint after completion and include the label or system reference where required.
UK fire guidance warns that gaps around cables and pipes can allow fire and smoke to pass and highlights risers and service cupboards. See the official guidance on penetrations and compartmentation. As one documentation example, the Hilti CFS-DM instructions explicitly separate pre- and post-installation photos.
Limit: a photo supports traceability, but it does not prove on its own that a seal, damper or service complies with the tested system, design or applicable rules.
6. The five views that make hidden work recoverable
View
What it must show
Common failure
Location
Room, grid, door, column, façade or another recognisable reference.
Starting with an impossible-to-place close-up.
Overview
The systems and their relationship to the space.
So wide that the services cannot be read.
Route
Continuity from origin to destination with overlap.
Gaps that prevent the route being reconstructed.
Detail
Branch, joint, box, valve, support, penetration or issue.
Blur, poor light or no scale where size matters.
Final state
Repair, completed seal or area ready for closure.
Keeping only the earlier defective condition.
7. Organise the protocol with Pic on Site
1. Define areas and milestones
Prepare the list of floors, rooms and planned close-ups before the trade finishes the area.
2. Capture one sequence per point
Keep the order location, overview, route and detail; add the corrected state where needed.
3. Relate the photo to the project
When valid GPS exists, Pic on Site can help position it. Indoors, verify the point against the plan, area and fixed references.
4. Retrieve by date, author and content
Centralisation keeps the record independent of one person's phone and makes later technical review easier.
5. Finish with a decision
Record whether closure can proceed, what remains, who owns it and when it will be checked again.
The floor, area and camera direction can be identified without relying on memory.
An overview and a continuous route are present.
Branches, boxes, valves, supports, access points and changes of direction have detail views.
Wall and slab penetrations are recorded before and after sealing where relevant.
Images are sharp, exposed correctly and unobstructed.
Corrected issues have a comparable follow-up image.
Date, author, area, system, status and document reference can be retrieved.
Required inspections, tests and approvals are recorded separately.
9. Safety, privacy and evidence limits
Do not remove protection, change a safe route or approach live equipment to improve a frame. Avoid faces, screens, documents and unrelated personal information. The European Commission explains when GDPR applies.
A photo shows: a visible condition from one viewpoint at one moment. It does not show: what is out of frame, internal performance, a test result, full regulatory conformity or contractual acceptance.
10. Questions and references
When should photos be taken?
After installation and checking, but before the element that hides the work is installed. Repeat after any correction.
Does a photo certify the work?
No. It supports a technical record but does not replace inspection, testing, measurement, certification or contractual as-built information.
