Changes and variations
Pricing a change while everyone still remembers the conversation, getting a decision that holds up, and what happens to the contract sum.
Updated 16 September 2026
The most expensive habit in domestic building is the change nobody wrote down. The client asks for a second socket while the sparks is on site; six weeks later there is £340 on the final bill and two people who each honestly remember the conversation differently. Neither of them is lying. There is just no record.
A variation in BuildFlow is that record. It carries what changed, what it costs, what it does to the programme — and a decision with a name and a timestamp against it.
Raising one
Project → Money → Raise a change. It is built to be finishable standing in a hallway, because that is where the conversation happens.
- 1
Say what is changing
“Second socket to the study”. The reference — VO-001, VO-002 — is assigned for you, per project, and it is how both of you will refer to it in every conversation afterwards.
- 2
Price it
Excluding VAT. If the change takes work out rather than adding it, turn on This is a credit — you do not need to type a minus sign on a phone keyboard.
- 3
Say what it does to the programme
In days. Use a minus for time saved. It is not automatic — BuildFlow will not move your target completion date behind your back — but the total is shown on the money screen so the conversation about the end date has a number in it.
- 4
Write the detail
This is what your client reads, and what gets read back in six months. Worth a sentence more than feels necessary.
- 5
Save it, or save and send
A draft is yours alone. Your client sees nothing until you send it.
Omissions are variations too
A client who drops the underfloor heating has varied the contract just as much as one who adds a rooflight. Record it as a credit. Aside from being right, a system that can only ever add looks to a client like it is only pointed one way.
Getting a decision
Once sent, it appears on your client's Payments tab with two buttons. Approving tells them in pounds what they are agreeing to and what it brings the price to; turning it down invites a reason, because “not at that price” is a negotiation and a bare no is a dead end.
Their name and the minute are recorded against it, and neither of you can change it afterwards. To alter a change that has been decided, withdraw it and raise another — which leaves both on the record, where they belong.
| State | Means | Who moves it |
|---|---|---|
| Not sent | A draft. Only you can see it | You |
| Waiting on the client | Sent, not yet answered | The client — or you, recording their answer |
| Approved | In the contract sum | The client |
| Rejected | Not happening at that price | The client |
| Withdrawn | You took it back before an answer | You |
When your client will not use the app
Plenty won't. Record their answer is for an approval that arrived by email, on a signed variation sheet, or over the phone. It asks which of those it was and insists on a note saying when and what was said.
That is more work than tapping Approve, and deliberately so. This is the record that has to stand up when a client says they never agreed, and a one-tap version of it would be worth nothing at all.
The two kinds of approval do not look the same, and shouldn't
“Sam tapped Approve at 14:32 on the 9th” and “Dave says Sam agreed on the phone” are different kinds of evidence. BuildFlow will not let you enter the second as the first — the channel “in BuildFlow” is the one thing only your client can produce. The screen and the handover pack both print which kind each one is, and your client is notified the moment you record one, so anything you have wrong surfaces now rather than at the final account.
- By email — keep the email. The note should say when it arrived and from which address.
- In writing — a signed variation sheet, a letter, a message thread.
- Verbally — the weakest kind. Say who said it, when, and who else heard it.
What it does to the money
Only approved changes count. One waiting on an answer is not in the contract sum, and BuildFlow says so rather than quietly including it — budgeting against a decision nobody has made is how a builder ends up funding somebody else's rooflight.
| Figure | What it is |
|---|---|
| Original contract sum | What was signed. It never moves, however many changes are approved |
| Approved changes | The net of everything agreed — extras up, credits down |
| Contract sum | The two added together. This is what the money screen leads with |
| Outstanding | The current sum less what has been paid |
Never edit the original to absorb a variation
It is tempting — one figure is simpler than three. But the original is the evidence that the extras were extras, and once it has moved there is nothing to show your client agreed to anything. BuildFlow keeps both on purpose.
An approved change is not automatically in your payment schedule. If you want to be paid for it as its own stage, add one — the money screen tells you when the schedule and the contract sum have stopped agreeing, which is usually exactly this.
Who can see what
| Drafts | Sent and decided changes | Can decide | |
|---|---|---|---|
| You and your admins | Yes | Yes | Only by recording an answer |
| Your client | No | Yes | Yes |
| Employees and subcontractors | No | No | No |
Site staff see no part of the money — not the contract sum, not the payment schedule, not the changes. What you charge your client is between you and your client, and a subcontractor's own price for the same work usually sits a long way below it.
What ends up in the handover pack
Every decided change: reference, description, price, the date it was decided, how, and any note either of you left. Rejections included — a client who turned something down has as much interest in that being on the record as in what they accepted.
Habits worth having
- Price it the same day. A change priced on the day is a conversation; the same change priced at the end is an argument.
- Send it before the work starts. An approval that arrives after the socket is in is worth much less than one that arrives before.
- Write the detail as though you will not be there to explain it. In a dispute, you won't be — the words will.
- Record the credits. They cost you nothing and they buy a great deal of trust.
- One change, one variation. Bundling four things into “sundry extras — £2,400” gives your client one thing to refuse instead of four things to agree to.
Which plans have it
Basic and above, with the rest of the contract and payment features.