Reading a Bill of Quantities: What Developers Should Check Before Signing Off

Most developers and project owners are not quantity surveyors, and they are not expected to be. But a Bill of Quantities (BOQ) is one of the few documents that will be referred back to at every stage of a project — pricing, valuation, variation, dispute — so it is worth knowing what a well-prepared one actually looks like before you sign off on it.

1. Does it match the drawings you approved?

A BOQ should be a direct, traceable translation of the approved drawings and specification into measured quantities. If the design has changed since the last BOQ revision and the quantities have not been updated to match, every downstream valuation will be measuring against an out-of-date baseline.

2. Are the descriptions specific enough to price accurately?

Generic descriptions ("supply and install tiling — allow") invite contractors to price conservatively or inconsistently, because everyone is guessing at the same missing detail differently. Look for descriptions that reference the specification clause, material standard, and location, so every bidder is pricing the same scope.

3. Is provisional and prime cost work clearly separated?

Provisional sums (for work not yet fully designed) and prime cost sums (for nominated suppliers or subcontractors) are normal on most projects — but they should be clearly labelled as such, with a note on how they will be finalised. A BOQ that buries provisional work inside firm quantities makes it harder to track what is genuinely fixed-price and what is still exposed to change.

4. Do the quantities reconcile with the cost plan?

Before a BOQ goes to tender, its total should be checked against the latest approved cost plan or budget. A gap between the two is not automatically a problem — but it needs to be understood and explained before tender, not discovered afterwards when bids come back higher than expected.

5. Who prepared it, and what is their process?

A BOQ prepared by a dedicated Quantity Surveying practice — measured directly from drawings, checked against specification, and reconciled against budget — carries a different level of reliability than one assembled quickly as a formality. It is reasonable to ask how a BOQ was produced before relying on it for a tender that will shape your project's entire cost trajectory.

The bottom line

You do not need to measure the building yourself. But asking these five questions before approving a Bill of Quantities takes a few minutes, and it is far cheaper than discovering the answers during a dispute over a variation eighteen months into construction.