Capturing variations, time and materials on site by voice note

To record a variation on site, send a voice note within minutes of agreeing it: job, what changed, who asked, the time and materials, and the price agreed. Then send the customer a written confirmation the same day and get a "yes" back before you do the work. A dated message trail settles most arguments at the final bill.

Why do variations go unpaid?

Because they're agreed in a conversation and remembered differently at the end. A homeowner asks for two more sockets while you're there, you say "no problem", and by the final invoice they remember it as included. Owners told us the evening write-up is where it fails. One renovation builder said of his site agreements: "By the time I sit down to write it down, it's gone."

The fix is to capture the change where it happens and confirm it before the work, not after.

He moved to recording variations by voice note from site, and they went onto the job and into the final account without the evening write-up.

What should the voice note say?

Five things, in the same order every time, so anyone can turn it into paperwork. It takes under a minute.

1. The job.

   Address or customer name: "Mill Lane, Mrs Patel's kitchen."

2. What changed.

   Plain words: "Add two double radiators in the extension, 600 by 1,000."

3. Who asked and when.

   "Customer asked this morning, 10am."

4. Time and materials.

   "Three hours, two rads, valves, about four metres of 15mm."

5. The price you agreed or will quote.

   "Told her about £420 including VAT, confirming in writing."

Send it to whoever prepares your paperwork, or to yourself in a WhatsApp chat you keep for the job. If you have engineers on site, give them the same script; see getting engineers to report time and materials.

How do you price the extra on the spot?

Use your normal rates, worked the same way as the main quote. If you don't know your day rate, work it out first with overheads per man-day.

How do you confirm a variation in writing?

Send a short message the same day and ask for a reply. WhatsApp or email both work, because each leaves a dated record. Use this template.

Hi customer name, confirming the change we agreed today at address:

Change: what's being added, removed or changed
Price: £amount including / plus VAT
Time: adds about x hours / days to the job
Payment: added to the next stage / final invoice

Please reply "agreed" and we'll go ahead. If anything's not right, let me know before we start.

Thanks, your name, Firm name

Does a voice note or WhatsApp count on a commercial job?

It helps, but check your contract first. Since the 2011 changes, the Construction Act applies to oral and part-oral construction contracts, so payment and adjudication rights don't depend on a signed paper contract. Most standard subcontracts still set out how variations must be instructed, often in writing and sometimes by a named person. Follow that process, and use the voice note and confirmation as your evidence.

On a commercial job, add the instruction reference or the name of the person who gave it, and keep a running tracker per job: variation number, description, price, instructed by, date, invoiced. If a dispute comes up over a significant sum, get advice from a solicitor or a construction claims specialist before it escalates. For payment notices and timings, see the pay less notice guide.

What if the job gets smaller?

Record it the same way. An omission, such as the customer deciding to keep the old bathroom floor, is a variation too, and leaving it off the paperwork causes as many arguments at the final bill as an unrecorded extra. Note what's been taken out, the credit you'll give, and whether materials already ordered can be returned or must be charged. Confirm it in writing with the same template, with the price shown as a credit.

What about time and materials work?

Record it the same way, daily. On a day-work or time-and-materials job, a voice note at the end of each day with hours, people and materials used becomes the timesheet. Keep the merchant receipts with it: a photo into the same chat is enough.

Common questions