This looks like a safety document and it is a commercial one
Site diaries get filed under paperwork and forgotten, and then a job goes wrong and the diary is the most valuable document anybody kept.
A delay or disruption claim is built almost entirely out of contemporaneous records: who was on site, what stopped, from when until when, and who said what. An entry written on the day is evidence. The same account written from memory six months later, when the argument has started, is a recollection, and everybody in the room knows the difference.
That is the whole reason to spend five minutes on this at the end of a day rather than reconstructing a fortnight of it later.
The three fields that do the work
Headcount, by trade
Standing time is priced per man hour. "The metalwork lads were held up most of the morning" cannot be costed by anybody. "Four metalworkers, held up 11:00 to 13:30" is ten man hours, and ten man hours has a rate against it.
So the labour block asks for a number and hours rather than a description, and totals the man hours present as you fill it in. Present, not worked, which is exactly the distinction a claim turns on.
Times on every delay
Duration is the claim. A delay recorded as "waiting on drawings, most of the afternoon" is an anecdote.
Delays with no times are counted separately and left out of the total, and the tool tells you how many there are. That is deliberate: a total that quietly includes guesses is a total somebody else can pull apart, and it is better to show a smaller defensible number plus a note than a larger one that will not survive being questioned.
A name on every verbal instruction
Verbal instructions are the ones that get disputed, every time. Somebody says leave that bay open, the crew leaves it open, and two months later nobody remembers agreeing to it.
Writing down who said it and when, on the day it was said, is frequently the difference between a variation and an argument. The tool nags about an instruction with nobody named and does not nag about a delivery, because only one of the two needs a name to be worth anything later.
Weather, because it is the most disputed cause there is
Exceptionally adverse weather is one of the most commonly claimed causes of delay and by a wide margin the most commonly challenged.
Naming the weather is not enough. "Rain" on its own proves nothing, because it rains and work continues. "Rain from 11:00, standing water on the level 3 slab, edge work stopped and the crew moved inside" describes a consequence, and a consequence is what is being claimed.
The temperature is worth recording even on an unremarkable day, because it governs concrete, mortar and some hot work, and nobody ever remembers it afterwards.
What a diary is not
It is not a notice. This is the one thing on this page that could cost somebody real money if it is misunderstood.
Most construction contracts require formal notice, in a stated form and within a stated period, for delay, variation or an extension of time. Writing something in a diary gives notice to nobody. The diary is what supports the notice when it is challenged; it does not replace it, and a perfect diary alongside a missed notice period is a familiar and expensive combination.
Check what your own contract requires and by when. That is a question about your contract, not about this tool.
One caution about how it saves
Nothing is uploaded, which is the point, and nothing is kept between visits either. Download the PDF at the end of each day rather than intending to come back to it, because closing the tab loses it.
That is the trade for having no account and no server holding your commercial records. On a document that names who was on your site and what went wrong, it seems the right way round.
Common questions
What is a site diary actually for?
Money, mostly. The safety value is real but modest. What pays for the five minutes is that a diary written on the day is contemporaneous evidence, and a delay or disruption claim is largely built out of contemporaneous evidence: who was standing about, from when until when, and why. A recollection written six months later is worth very little by comparison.
Why does it want the number of people rather than just the trades?
Because standing time is priced per man hour. "The metalwork crew were held up all morning" cannot be costed. "Four metalworkers held up from 11:00 to 13:30" can. The tool works out man hours present as you go for the same reason.
Why does it keep asking for start and finish times?
Duration is the claim. A delay with no times is an anecdote, and the tool says so rather than quietly totalling it as zero. Delays with no times are counted separately and left out of the total, because a total that includes guesses is a total somebody can attack.
Why does it single out verbal instructions?
Because they are the ones that get disputed. An instruction given on the phone or across a slab, with nobody named and nothing written, is very hard to rely on later. Writing down who said it and when, on the day, is often the difference between a variation and an argument.
Is this a notice under my contract?
No, and this matters. Most construction contracts require formal notice within a set period for delay, variation or extension of time, and writing something in a diary does not give notice to anybody. The diary supports a notice; it does not replace one. Check what your contract requires and by when.
Is my diary saved anywhere?
No. Nothing is uploaded, and nothing is stored between visits either, so download the PDF at the end of each day rather than intending to come back to it. That is the trade for a tool with no account and no server holding your commercial records.