Site Diary: What to Record Every Day (and Why It Wins Disputes)

Pro Site Docs · Guide

Ask a construction solicitor which document wins delay claims and the answer is nearly always the same: the site diary, written on the day, by the person who was there. It is also the first thing HSE asks for after an accident. No regulation requires it. Every experienced site manager keeps one.

Why it matters

A diary written at the time is contemporaneous evidence. A statement written six months later is memory. In a dispute about who caused a delay, what was instructed, whether the ground was as expected or whether the site was closed for weather, the party with the diary usually wins. Under NEC and JCT contracts the early-warning and notification clauses have time limits, and the diary is how you prove when you knew.

After an incident, the diary shows who was on site, what was happening, what supervision was in place and what the conditions were. It is the difference between 'we think' and 'we know'.

What to record every day

• Weather - conditions morning and afternoon, temperature, anything that stopped work, with times
• Labour - who was on site, by trade and company, including subcontractors and visitors
• Plant - what was on site, working or standing, and why
• Work done - by area, in plain terms: 'drainage run MH3 to MH4 laid and backfilled', not 'drainage'
• Instructions - anything the client, engineer or principal contractor told you to do, who said it and when, and whether it was confirmed in writing
• Delays and problems - unexpected ground, services not where shown, materials not delivered, areas not available, with times and who was told
• Health and safety - inductions, toolbox talks, inspections, near misses, accidents, visits by HSE or the client's safety team
• Deliveries received and rejected
• Photographs - referenced by number, taken on the day

Who writes it

The person in charge of the site that day. If the site manager is off, the supervisor writes it and says so. One diary per site, not one per person, unless the contract says otherwise. Subcontractors should keep their own for their own works - the main contractor's diary will not be written to protect you.

Keeping it credible

Write it on the day. A diary filled in on Friday for the week reads like one, and a court will treat it as such. Never alter an entry - if something was wrong, add a dated correction. Sign and date each page. If it is digital, use a system that timestamps entries and does not allow silent editing. Keep it factual: what happened, not what you thought of the person who caused it.

How long to keep it

For the life of the project and then for at least six years, which is the normal limitation period for a contract claim - twelve if the contract is executed as a deed. Anything touching on an injury is kept longer. It costs nothing to keep and it has settled more arguments than any other document on site.

Get the documents ready-made

Our Site Manager Toolkit includes a site diary template alongside the daily and weekly records a site actually runs on, or take individual registers and trackers.

General guidance only. This article explains how the rules generally work in UK construction. It is not advice for your specific site, task or project, and it is not legal advice. Your own risk assessment, method statement and arrangements must be prepared and checked by a competent person for the actual work being done.