How to keep a construction site diary
A site diary is the chronological, day-by-day account of a construction project, kept by the site manager. In UK, Irish and Australian practice it is the document adjudicators reach for first — provided it was written contemporaneously, covers bad days as honestly as good ones, and never leaves a gap.
What goes in a site diary entry
Every working day, without exception:
- Resources: labor by trade and subcontractor, plant on site and whether it worked.
- Progress: activities carried out, by location, with approximate quantities.
- Conditions: weather at intervals through the day and its effect on the work.
- Events: instructions received, inspections, visitors, deliveries, stoppages, disputes, near misses.
- Information flow: drawings received or missing, RFIs raised and answered.
The test for every entry: could someone who was not there reconstruct the day from it? If yes, it will serve you in a dispute three years from now.
Why site diaries win (or lose) disputes
Adjudicators and courts weight evidence by when it was created. A diary entry written the day of the event, in the normal course of business, outweighs almost any witness statement drafted after the dispute began. That cuts both ways:
- A diary with gaps on the critical days reads as though something is being hidden.
- A diary that records only progress, never problems, gives you nothing to build a delay or disruption claim on.
- A diary obviously written in one sitting — same pen, same phrasing, dated across three weeks — gets discounted entirely.
Digital diaries with immutable timestamps sidestep the authenticity question completely: each entry proves when it was made.
Keeping it sustainable
The classic failure mode is the site manager saving the diary for the evening, then losing the evening to a subcontractor call. The fix is to capture in fragments during the day — a photo here, a delay note there — and let the diary assemble from the fragments. That is precisely what field apps changed about diary-keeping: the diary became the byproduct of running the site rather than an extra hour after it.
Doing this in TerenIQ
TerenIQ works as a site diary app that fills itself in as you run the day:
- Photos, tasks, inspections, briefs and deliveries logged during the day become the diary's entries — each stamped with author, GPS and time.
- Weather is recorded automatically for every site, every day.
- History is preserved: nothing can be quietly edited after the fact, which is exactly what makes a diary credible.
- The iPhone app is offline-first, so the diary keeps building in basements and dead zones and syncs when coverage returns.
Frequently asked questions
Is a site diary a legal requirement?
Rarely by statute, but very commonly by contract — and practically always in your interest. If the contract names a site diary, keeping it badly is a breach; keeping it well is leverage.
Who owns the site diary?
The party whose employee keeps it — usually the main contractor. Subcontractors should keep their own records rather than rely on someone else's diary.
Site diary vs daily report — do I need both?
They overlap heavily. Keep one complete daily record and generate the distributable report from it; see our guide on the construction daily report.