Civil and Precast Construction · Question

What is a bill of quantities and why does it matter in a civil contract?

Short answer

A bill of quantities, often called a BOQ, is an itemised list of the work in a project, showing each item's description, unit, quantity and price. It turns drawings and specifications into a priced schedule. It matters because it lets you compare bids on equal terms, measure work done for payment and price changes later without arguing from scratch.

In more detail

Imagine a contractor quoting for a warehouse foundation. Without a schedule, the quote might say one amount for foundation work. With a BOQ, the work is broken into excavation, concrete, reinforcement steel, formwork, backfilling and similar items, each with a quantity taken from the drawings and a price per unit.

The quantities usually come from a quantity surveyor or the design team measuring the drawings, though some contractors prepare their own. When several contractors price the same schedule, differences show up in rates, not in what each assumed was included.

What each column tells you
Column	What to look for
Description	Clear wording tied to the specification
Unit	Cubic, square or running measure suited to the item
Quantity	Figure derived from drawings, not a guess
Rate and amount	Price per unit and the total for that line

An owner reading a BOQ should look for items that are missing, lumped vaguely or marked provisional. Provisional sums hold a place for work whose scope is not yet known, so they are the likeliest source of later cost increases. Check that the drawings and specifications referred to in the BOQ are the same version you intend to build from.

Keep it alive after signing

Use the same BOQ format for running bills and for pricing any added work, so everyone measures against one reference.

A BOQ is only as good as the drawings behind it. If design is incomplete, quantities are estimates, and the final cost is decided by measurement after the work is done. In an item rate contract, that remeasurement drives payment; in a lump sum contract, the BOQ mainly serves as a pricing and variation reference.

Key points

A BOQ lists every work item with unit, quantity and rate, creating one comparable pricing basis.
Provisional sums and vague lump items deserve questions before signing.
Quantities depend on drawing completeness, so incomplete design means uncertain totals.
The same schedule supports bill verification and variation pricing later.

Who this applies to

Owners receiving a contractor's pricing document and wanting to understand it.
Finance teams approving project budgets and stage payments.
Developers comparing several civil contractors on one project.

Last reviewed 3 October 2026

This answer is general information, not advice on your particular case. Terms, eligibility, and requirements change, so check the current position with the relevant institution or authority.