Bill of Quantities (BOQ)
The bill of quantities breaks the project down into sections and measurable items: excavation, foundations, structure, masonry, MEP installations, finishes, and so on. Each line identifies a specific task with a code, a technical description, the unit of measure (sq ft, cu yd, linear ft, each, ton, lot) and the quantity of work to be executed, which comes from the takeoff of the drawings.
When you assign a unit price to each item, the bill of quantities becomes the construction estimate: unit price × quantity = item amount, and the sum of all amounts gives the total. The same BOQ is then used to measure physical and financial progress, since payment applications are generated item by item based on what has actually been built.
In public procurement, the bill of quantities is the core document of the tender: the owner issues it to bidders so they price the unit rates against fixed quantities, which lets proposals be compared on a like-for-like basis. A poorly defined item or a wrong quantity later turns into overruns, extra work orders or disputes with the client.
Example
BOQ for a slab: the item "Concrete f′c=3,600 psi in slab, includes placing, vibrating and curing", code 04-020, unit cu yd, quantity 60.00. If the unit price is 220/cu yd, the item amount is 60.00 × 220 = 13,200.
| Line item | Budget | Spent | Progress | Status |
|---|---|---|---|---|
| Concrete and foundation | $612,000 | $598,000 | On track | |
| Steel structure | $486,000 | $502,000 | Over budget | |
| MEP systems | $398,000 | $240,000 | In progress | |
| Masonry | $354,000 | $160,000 | In progress | |
| Finishes | $520,000 | $70,000 | In progress |
Frequently asked questions
What is the difference between a bill of quantities and a construction estimate?
The bill of quantities is the list of work items with their code, description, unit and quantity, without prices. Once you assign a unit price to each item and multiply it by its quantity, the BOQ becomes the construction estimate.
What information does each BOQ line item contain?
A code or item number, a technical description of the work, the unit of measure (sq ft, cu yd, linear ft, each, ton) and the quantity of work to be executed. The estimate then adds the unit price and the amount.
Where do the quantities in a bill of quantities come from?
From the takeoff or measured quantities obtained from the project drawings: areas, volumes and lengths of each element are measured to determine the quantity of each item.