Guides, Pricing jobs
How to show preliminaries and profit on a quote
Work them out as separate percentages on your building work so you can see them, then share them across the parts of the job your client reads. They get whole sums that add up, and you keep sight of your margin.
By the builderplus team. Last checked 1 November 2026.
Preliminaries are what it costs to run the job and aren’t part of any one trade: scaffold, skips, toilets, insurance, site set-up, supervision. Overheads are what it costs to run your business. Profit is why you’re doing it.
The mistake is hiding all three inside your rates, because then you can’t see what you’re making or change it when a job’s tight.
Keep them separate when you price
Price the building work first, trade by trade. Then add each as a percentage of that figure.
Here’s a made-up rear extension, to show the sums:
| Building work | £30,912 |
| Preliminaries at 10% | £3,091 |
| Overheads and profit at 15% | £4,637 |
| Before VAT | £38,640 |
| VAT at 20% | £7,728 |
| The price | £46,368 |
The percentages here are only an example. Yours depend on your costs and on the job: a tight site with no parking needs more preliminaries than an open one.
Work out your overheads once
Add up a year of running costs: van, insurance, phone, accountant, your own time that isn’t on site. Divide by the value of work you expect to do in a year. That percentage is your overhead, and it means your margin is based on your real costs and not on a habit.
Show your client parts, not your percentages
A homeowner doesn’t need to see “overheads and profit, 15%”. It invites an argument about a figure they can’t judge. Share those amounts across the parts of the job, in proportion, so each part carries its fair share:
| What they read | |
|---|---|
| Groundworks and drainage | £8,420 |
| Walls and structure | £17,960 |
| Roof and glazing | £6,180 |
| Finishes and fit-out | £13,808 |
| Including VAT | £46,368 |
They can see what they’re paying for, and it adds up. You’ve still got every figure behind it.
When they ask you to take something out
Because each part is priced with its share, you can take one out and the rest still stands. Before you agree, check that what’s left still covers your preliminaries. A smaller job often has nearly the same scaffold and skips.
builderplus keeps your percentages on the bill and shares them across the plain parts on the quote, so the parts always add up to the total. Start free.