In builder quotes, the words used around allowances matter. A client may read a total as a complete commitment. A builder may see parts of that total as placeholders, assumptions or selections still to be agreed. If that difference is not made explicit, the gap becomes a commercial dispute later.
What PC sums and provisional allowances mean in practice
A PC sum is usually used for a supply item where the exact client selection is not known yet, such as sanitaryware, tiles, appliances, ironmongery or a kitchen package. A provisional allowance is broader: it is an allowance for work or cost that is expected but not defined enough to price with full confidence.
The practical difference is important. A PC sum might cover the product allowance only. It may not include labour, fixings, waste, handling, prelims, margin or programme impact. A provisional allowance may cover a work package, but it should still have a stated basis.
PC sum vs provisional allowance vs exclusion
| Term | Best used for | Builder risk if unclear |
|---|---|---|
| PC sum | Client-selected supply items where the final choice is unknown. | The client may assume installation, uplift or higher-spec selections are included. |
| Provisional allowance | Work likely required but not defined enough for a reliable fixed price. | The allowance may be treated as a complete fixed-price commitment. |
| Priced assumption | A reasonable first-pass price based on an explicit assumption. | The assumption may be forgotten once the client sees the total. |
| Exclusion | Work not priced or not included in the current scope. | The client may assume it is included if the exclusion is vague or hidden. |
Useful quote wording
Wording should make the commercial basis clear without turning the client quote into a wall of legal text. The aim is clarity: what is allowed, what is excluded and what happens if the final selection or scope changes.
Sanitaryware supply allowed as PC sum of £3,500 excluding specialist installation requirements, non-standard fixings and client upgrades above allowance.
Drainage alterations included as provisional allowance pending survey and confirmation of existing drainage route. Final cost subject to confirmed run, depth, access and required chambers.
Roofing priced on assumed warm flat roof system to standard specification. Warranty, insulation build-up and rooflight detailing to be confirmed before final order.
Allowance review checklist
- Does each allowance say whether it is supply only, install only or supply and install?
- Does the quote separate the allowance from labour, prelims, margin and contingency where needed?
- Does the builder know what happens if the client chooses a higher-spec item?
- Are provisional areas connected to specific missing information?
- Are exclusions visible enough that the client cannot reasonably miss them?
Why this matters more in fixed-price quotes
In a cost-plus workflow, uncertainty can sometimes be dealt with as the project develops. In a fixed-price quote, uncertainty lands differently. If an allowance is unclear, the builder may be expected to absorb the difference. That is why allowances should be reviewed before margin and final presentation.
The quote can still be simple for the client. The internal working should be more detailed than the client summary, so the builder knows which parts of the number are firm and which parts need a decision.
How Quotify helps
Quotify separates PC sums, provisional areas, assumptions, exclusions and missing information inside the quote pack. That gives the builder a clearer first-pass structure before deciding what should appear in the client-ready quote.
The result is not an automatic final price. It is a builder-reviewed quote pack that keeps the commercial basis visible.
Send the project details or existing quote. Quotify can help structure the pack so PC sums, provisional areas and assumptions are separated before the number goes to the client.