Hidden work: which photos and certificates to keep

What hidden work is

Hidden work is work that the next stage will cover for good. Afterwards it can only be checked by opening it up. In the app's route, such work appears in these stages:

• “Partitions” - framing, backing plates, cables inside the partition;
• “Plumbing” - pipes, manifolds, outlets;
• “Electrical” - cables, back boxes, the panel, equipotential bonding in the bathroom;
• “Air conditioning” - copper lines, drainage, power;
• “Rough finishing” - the window seam under the reveals, cables before the second side of partitions is boarded;
• “Floor preparation and screed” - pipes and cables in the floor, underfloor heating, sound insulation, the drain;
• “Waterproofing” - tapes, collars, the height on the walls;
• “Ceilings” and “Stretch ceiling” - framing, backing plates, lines and ducts above the ceiling;
• “Tiling” - underfloor heating mats under the tiles.

In a private house, the roof membrane and the heating pipes before the screed are added to these. The full list of photo items by stage is in Photos of hidden work.

Photos: how to take them so they're useful

The route's hints repeat one rule: the contractor photographs before closing, the owner or designer checks. A photo that will help you find a cable five years from now looks like this:

• each wall in full, from corner to corner, then the joints close up;
• a tape measure in the shot - from the floor or a corner, so you can measure the spot from the photo;
• the room and wall are labelled;
• before closing, not “roughly how it was”.

A photo without a tape measure shows that a cable is there, but not where. And wiring embedded in a wall or screed can't be replaced (that's how SP 256.1325800.2016, clause 15.5, describes it), so its routes must be photographed before plastering.

Tests: the numbers worth recording

A photo shows that the work is there. A test shows that it works. The app's route has these items:

• water pipes (“Plumbing”) - a photo of the pressure gauge at the start and end of the pressure test;
• electrical circuits (“Electrical”) - insulation tester readings, at least 0.5 MΩ, in a photo;
• underfloor heating cable (“Floor preparation and screed”, “Tiling”) - resistance before and after laying;
• waterproofing (“Waterproofing”) - the flood test result: a day, and the neighbours below are dry;
• air conditioner lines (“Air conditioning”) - a pressure test before the walls are closed;
• heating in a private house (“Heating and boiler room”) - a pressure test certificate with the pressure and hold time.

For the underfloor heating cable the route's hint says specifically: the warranty asks for the layout with a tape measure and the resistance. More on tests in Plumbing: pressure testing and checks before boxing in and Apartment wiring: what to check before plastering.

Diagrams

Besides photos, it's worth keeping diagrams:

• the electrical panel diagram - which breaker does what; it'll come in handy with any fault;
• the utility line plan on the plot for a private house - it saves the pipes during digging;
• the working drawings the crew used: elevations, wiring and plumbing diagrams, the tile layout.

Acceptance before closing

The last item of a stage with hidden work is acceptance. For example, “Accept the work before the screed is poured” or “Accept the lines before plastering”. The point is that the next tradesperson doesn't start until the hidden work has been checked.

In the app it looks like this:

1. The contractor attaches photos to the items and taps “Send for review”.
2. You or the designer look at the photos and tap “Accept work” or “I have remarks”.
3. Who accepted the work and when stays in “Property history”: the bell on Home → “Property history”.

Photos of an item sent for review or accepted can't be deleted - they are proof of the work. How to review work stage by stage is in How to accept a crew's work stage by stage.

A hidden work certificate

The term comes from construction: there, certificates for hidden work are part of the as-built documentation. In an apartment renovation under a contract with a crew, such a certificate is whatever you agree on. A convenient option is to write into the contract:

• which work is accepted before closing: pipes, wiring, underfloor heating, waterproofing;
• what counts as confirmation: photos following the rules above, test results, a signature or an acceptance mark;
• that the next stage doesn't start without acceptance of the previous one.

How to put the contract together is in The contract with a renovation crew: what to include. If you sign a paper certificate, photograph it and put it in the “Documents” tab, the “Contracts” folder.

Where to keep everything

• Photos for items - the “Stages” tab, the “Photo records” block of the item. All property photos are collected in the “Documents” tab, the “Photo records” folder.
• Certificates and reports - “Documents” → “Contracts”.
• Spec sheets for equipment and meters - “Documents” → “Spec sheets” and “Meters”.
• Export - “Documents” → “Property passport export” → “PDF” or “Excel”.

How long to keep these documents after the renovation is in Which documents to keep after a renovation.

Checklist before each closing

• Each wall is photographed in full, the joints close up.
• The photos have a tape measure and a room label.
• The test is done, the number recorded and photographed.
• The panel or pipework diagram is saved.
• The stage is accepted in the app before the next one starts.
• A paper certificate, if there is one, is photographed and in “Documents”.