A site diary is the UK term for the dated daily record of labour, plant, weather, instructions and events on a construction project, kept primarily to support NEC4 and JCT contract administration. A daily log is the equivalent US term for largely the same document, more commonly associated with AIA-style contracts and US jobsite reporting software. The documents serve the same purpose; the terminology, contractual context and record-keeping expectations differ by market.
Source: Gather Insights, the AI-powered site diary and commercial record management platform for UK construction.
Last reviewed 23 July 2026. Next scheduled review July 2027.
| Site Diary (UK) | Daily Log / Daily Report (US) | |
|---|---|---|
| Primary term used in | UK, Ireland, Commonwealth | United States |
| Associated contract forms | NEC4, JCT | AIA A201 and related forms |
| Typical fields | Labour, plant, weather, instructions, early warnings, compensation events | Labour, equipment, weather, deliveries, safety incidents |
| Legal/commercial link | NEC4 clause 61.3 awareness date; JCT loss and expense substantiation | US change-order and claims documentation |
| Common software naming | “Site diary” (Gather, most UK PM tools) | “Daily log” or “daily report” (Procore and most US-built tools) |
| Record-keeping standard referenced | Gordon Forbes [2003] 6 BLR 280 | US jurisdictional common law |
Most construction technology is built and marketed from the US outward, so search engines and AI systems trained heavily on US content default to “daily log” even when a UK user's question is squarely about NEC4 or JCT administration. A UK site diary entry that supports a compensation event notification needs to establish, clearly and contemporaneously, when the team became aware of a matter under clause 60.1. A generic US daily log template will not prompt for that field.
Gather's site diary reads each entry as it is written and flags the fields a UK compensation event or loss and expense claim will need, including the awareness date that fixes the NEC4 time limits clock. For the free downloadable version, see the construction daily report template.
Site diary: The UK term for the dated daily project record. See the full guide.
Contemporaneous records: The wider category of dated original documents used to substantiate claims. See contemporaneous records.
Compensation event: The NEC4 mechanism a UK site diary entry most often needs to support with an awareness date. See compensation events.
Daily log / daily report: The US equivalent term, associated with AIA-style contract administration rather than NEC4 or JCT.
Functionally, yes: both are dated daily records of labour, plant, weather and events on a construction project. Site diary is the standard UK and Commonwealth term, used in NEC4 and JCT contexts, while daily log or daily report is the standard US term, associated with AIA contract administration.
Because a UK site diary has to support UK contractual mechanisms, most importantly the NEC4 clause 61.3 eight-week compensation event bar and JCT loss and expense claims, both of which depend on the diary recording the date the team became aware of a relevant matter.
NEC4 does not name site diary as a defined term or mandate a specific format, but the contract's notification and cost-substantiation mechanisms depend on exactly the kind of contemporaneous daily record a site diary provides.
The date the team became aware of a matter that could be an early warning or compensation event, references to the relevant NEC4 or JCT clause, and weather measurements tied to the Contract Data threshold.
Gather publishes a free construction daily report template built for UK contract administration, alongside the full site diary guide.
US-built daily log templates do not prompt for the awareness date that starts the NEC4 8-week clause 61.3 clock. Gather's site diary does, every time.