The first hour after a verbal instruction

It usually happens on a walkaround. Somebody senior from the main contractor stops, looks at the work, says something like "that'll need to come out and go back in the other way round, crack on and we'll sort the paperwork", then walks on to the next thing. Ten seconds of speech. Depending on what happens in the next hour, those ten seconds become either an instruction you get paid for or a memory two people will describe differently in a meeting room next year.

Because here's the thing about the verbal layer of a construction project: it's where most of the real decisions get made and it's the one layer that keeps no record of itself. The drawings are filed, the emails are filed, the minutes get typed up by somebody with an interest in what they say. The sentence said next to the excavation at ten past nine exists nowhere at all unless you put it somewhere, and the window for putting it somewhere accurately is short. Not because anyone's dishonest, though the eternal site question of have we got that in writing exists for a reason, but because memory is soft and by Thursday even you won't be able to swear to the exact words.

So, the first hour, in order. This is a craft like any other and the people who are good at it are worth their weight.

1. Write it down straight away, while the words are still warm. Exact words as near as you can get them, who said them, the time, where you were stood and who else was in earshot. The back of the diary, your phone, it doesn't matter where it lands first. What matters is that it's written within minutes, not hours, because the version written at half four is already a reconstruction.

2. Confirm it back in writing before the hour is out. An email does the job: "Confirming your instruction this morning at approx 9.10 by the pumping station, to take out the section and rebuild handed, as discussed in front of your engineer. Please issue the formal instruction. We are treating this as a change." Plain words, no lawyering, sent to the person who said it with your office copied in. If they reply correcting you, that's a result too, because now you know what the instruction actually was while there's still time to argue about it.

3. Check what your contract needs before you act on it, because this is where the craft gets real. Most forms want instructions in writing to be valid and some are strict about it. Acting on a bare verbal can mean doing the work and never being paid for it. Your confirmation email is what converts the verbal into something with a date and an author, and if the formal instruction doesn't follow, chase it in writing and let the record show you chasing.

4. Tell your own QS the same day, not at the end of the week. They can't protect a change they don't know exists and a change that misses a valuation cycle has a habit of rolling to the end of the job, where it joins the pile marked "to be agreed" that we all know the fate of.

5. Start the cost record from the first minute of the changed work. Separate lines on the allocation sheet, the gang and plant hours against the change rather than buried in the day's general effort, photos before you touch anything and again as it comes out. Untangling changed work from base work three months later, from a single merged record, cannot honestly be done, and the other side knows it.

None of this is aggressive and none of it needs a single hostile word. Confirming an instruction in writing is what competent people do, the good main contractor QSs expect it and quietly respect it, and the ones who bristle at it are telling you something worth knowing. The whole routine costs perhaps fifteen minutes, which is a decent rate of pay when the alternative is arguing next spring about ten seconds of speech nobody wrote down.

Cut the five steps out and put them on the cabin wall. The first person it saves might not be you.

First in an occasional series of cabin-wall checklists: short disciplines worth pinning up where the kettle is.