What's wrong with using a spreadsheet for construction daily reporting?
Spreadsheets are office tools applied to a field recording problem. They require a desk to use properly, don't timestamp entries automatically, can't attach photos to specific events, and get filled in from memory at end of day. They solve the formatting problem. The recording problem, capturing what happened at the time it happened, they don't touch.
What are the problems with using a spreadsheet as a site diary?
The issues aren't about preference. They directly affect the value of the record.
No automatic timestamps. In a spreadsheet, you type the time, or you don't. There's no system record of when an entry was actually made. In a dispute, the other side can challenge when entries were really created. You have no proof of when entries were really made.
No photo linkage. Photos taken on site live in your camera roll. The spreadsheet entry references them, maybe. Cross-referencing photos to specific log entries requires manual discipline that doesn't survive a long shift. The photo and the entry exist in separate systems and drift apart.
Not usable on site. Try opening a spreadsheet on your phone in gloves. Navigate to the right row. Tap into a cell. Type something coherent with noise around you and rain on the screen. It takes two minutes minimum, so entries get deferred. Deferred means end of day. End of day means from memory.
Written from memory by design. That's not a side effect — the whole workflow is built around end-of-day completion. Every entry ends up made from memory, and a record written from memory can be challenged on exactly that basis. In adjudication, when the other side says "this was written up after the fact," a spreadsheet gives you nothing to push back with.
Can you use Google Sheets or Excel for a site diary?
Technically yes. In practice, the record you get has the same weaknesses as a paper diary, sometimes worse, because spreadsheets create an illusion of organisation while the underlying entries are still written from memory hours later.
A structured spreadsheet looks more credible than scrawled handwriting. But in adjudication, what matters is whether entries were made at the time. A tidy spreadsheet filled in from memory after knockoff doesn't answer that question any better than a messy paper diary does.
What does the timestamp actually prove?
An automatic system timestamp, applied the moment you log an entry and stored with it in the cloud, proves that the record was made at the time. That's what adjudicators look for when deciding whether a diary is genuine or written up later.
A spreadsheet where you typed "07:45" into a cell proves nothing about when you typed it. A system-generated timestamp is a different category of evidence entirely.
What does a better alternative look like?
Built for the field: phone-first, minimal interaction to log an entry, voice input so you don't need to type, automatic timestamps at the moment of recording, photos that link directly to the relevant entry, and PDF export that generates without reformatting.
The record is built throughout the day, entry by entry. End of day is a 60-second review and one tap to generate the PDF. That's what the difference looks like in practice.