Bill of Quantities (BOQ) Format

A bill of quantities (BOQ) breaks a construction project into every measurable item, such as cubic metres of concrete, square metres of plaster or the number of doors, and lists each with a unit and quantity so contractors can price it line by line. The BOQ format is simple: item, description, unit, quantity, rate and amount. What takes skill is measuring consistently and writing descriptions that leave no doubt about what is included. This guide covers the structure, a priced sample and how to build one in Excel.

Why a BOQ is used

When five contractors price a building from drawings alone, each measures differently, and the bids cannot be compared fairly. A BOQ fixes the quantities so every bidder prices the same thing. That gives the client a like-for-like comparison and gives everyone a shared basis for later valuations: if 20 extra square metres of blockwork are added, the agreed rate already exists.

In the UK and many Commonwealth markets, building BOQs are commonly measured to the RICS New Rules of Measurement. NRM 2, detailed measurement for building works, sets out how items are measured and described, and distinguishes firm bills (for a lump-sum price on a fully designed project) from approximate bills that are remeasured as built. Civil engineering work often uses a different method. Whatever method applies, state it in the BOQ preamble.

Standard bill of quantities format

Column	What goes in it	Example
Item / Ref	A unique reference, often section letter plus number	C.04
Description	The work, materials, standard and location	Blockwork, 100 mm dense concrete blocks in cement mortar 1:4, internal walls
Unit	The unit of measurement	m2
Quantity	Measured amount	86
Rate	Price per unit, filled in by the contractor	38.50
Amount	Quantity x rate	3,311.00

Common units

• m3 (cubic metres): excavation, concrete, fill.
• m2 (square metres): walls, plaster, paint, floor finishes, roofing.
• m (linear metres): skirting, pipes, kerbs, gutters.
• nr (number): doors, windows, sanitary fittings, light points.
• kg or t: reinforcement steel.
• item or sum: lump-sum items such as a temporary hoarding.

In US practice you will see cubic yards, square feet and linear feet instead; the structure is identical.

Typical sections

1. Preliminaries (site set-up, management, welfare, insurance, scaffolding).
2. Substructure (excavation, foundations, ground slab).
3. Frame and upper floors.
4. Walls and partitions.
5. Roof.
6. Windows and doors.
7. Finishes (wall, floor and ceiling).
8. Services (plumbing, electrical, mechanical), often priced by specialists.
9. External works.
10. Provisional sums, prime cost sums and contingencies.

Priced BOQ sample: single-storey rear extension

The figures below are illustrative. Your rates will depend on location, labour costs and suppliers.

Item	Description	Unit	Qty	Rate	Amount
Section B: Substructure
B.01	Excavate trench for strip foundation, max 1.0 m deep, remove spoil off site	m3	9.6	65.00	624.00
B.02	Concrete C25 in strip foundation, poured against earth	m3	7.2	145.00	1,044.00
B.03	Ground floor slab, 150 mm concrete on DPM, insulation and hardcore	m2	24	92.00	2,208.00
Section B subtotal					3,876.00
Section C: Walls
C.01	Cavity wall, facing brick outer leaf, 100 mm insulation, block inner leaf	m2	42	165.00	6,930.00
C.02	Steel lintel over opening, 2.4 m	nr	2	210.00	420.00
Section C subtotal					7,350.00
Section F: Finishes
F.01	Plasterboard and skim to internal walls	m2	48	28.00	1,344.00
F.02	Emulsion paint, mist coat and two coats, walls and ceiling	m2	72	9.50	684.00
Section F subtotal					2,028.00

BOQ summary

Section	Amount
A: Preliminaries (6 weeks x 650.00)	3,900.00
B: Substructure	3,876.00
C: Walls	7,350.00
F: Finishes	2,028.00
Provisional sum: electrical installation	2,500.00
Contingency (5% of measured work: 13,254.00 x 0.05)	662.70
Total excluding tax	20,316.70

Check the math: measured work is 3,876.00 + 7,350.00 + 2,028.00 = 13,254.00. Add preliminaries of 3,900.00, the 2,500.00 provisional sum and the 662.70 contingency, and the total is 20,316.70. Sales tax or VAT is added on the summary or the invoice, depending on local rules.

How quantities are measured: a worked example

Quantities in a BOQ come from "taking off" the drawings. Here is how the B.01 and C.01 figures in the sample were produced.

Trench excavation (B.01)

The extension's foundation runs along three sides: 4.0 m + 6.0 m + 4.0 m = 14.0 m of trench, but the drawings show the trench at 0.6 m wide and 1.0 m deep with corner overlaps, giving an effective length of 16.0 m. Volume = 16.0 x 0.6 x 1.0 = 9.6 m3. The concrete fill (B.02) is 16.0 x 0.6 x 0.75 m deep = 7.2 m3, because the top 250 mm of the trench is taken up by brickwork below ground level.

Cavity wall (C.01)

The external wall is 14.0 m long and 2.7 m high from floor to wall plate: 14.0 x 2.7 = 37.8 m2. Add the below-ground section between foundation and floor level, about 14.0 x 0.45 = 6.3 m2, giving 44.1 m2. Deduct the door opening of 2.4 x 2.1 = 5.04 m2 only if it exceeds the minimum deduction set by your measurement rules; here it does, so 44.1 - 5.04 = 39.06 m2. The sample rounds up to 42 m2 to include the returns at each end where the extension meets the house. In a real BOQ, you would measure those returns separately and record each dimension in "dimension sheets" so anyone can check the figure.

The lesson: every quantity should be traceable to a drawing and a calculation. If a client or surveyor questions a number, you should be able to show the working in minutes.

Provisional sums and prime cost sums

A provisional sum is an allowance for work that cannot be fully defined at tender, such as electrical work awaiting a design. It is adjusted to the actual cost later. A prime cost (PC) sum is an allowance for goods or work from a nominated supplier, such as a kitchen chosen by the client, to which the contractor adds handling and profit. Label both clearly so the client knows these figures will change.

How to make a BOQ in Excel

1. Create columns: Item, Description, Unit, Qty, Rate, Amount.
2. In the Amount column, use a formula such as =D5*E5 on each row and copy it down.
3. Group rows by section and add a subtotal row using SUM for each section.
4. Create a Summary sheet that references each section subtotal, then add preliminaries, provisional sums and contingency.
5. Add a preamble sheet stating the measurement method, drawings used, tax treatment and what rates include.
6. Lock formula cells and protect the sheet before sending it to bidders, so only the Rate column can be edited.
7. Export a PDF copy for the record alongside the editable file.

How contractors use a BOQ

• Pricing a tender: build up each rate from labour, materials and plant, then add overheads and profit. Our guide on job costing for contractors shows how to build a rate.
• Writing the bid: the priced BOQ supports your bid proposal and makes your number defensible.
• Interim payments: each month, value work done against BOQ quantities and rates. This is the foundation of progress billing.
• Valuing variations: extra or omitted work is valued at BOQ rates where the work is similar, which speeds up change orders.
• Final account: remeasured quantities and adjusted provisional sums produce the final contract sum.

For smaller jobs that do not need a full BOQ, an itemised construction quotation with quantities and unit rates gives the client much of the same clarity.

BOQ format variations by country

The six-column structure is the same almost everywhere, but conventions differ. UK and Commonwealth bills often follow NRM 2 and use metric units with VAT added on the summary. In India, Pakistan and the Gulf, public works BOQs frequently follow schedules of rates published by government departments, and items may reference those schedule codes. US contractors more often work from a schedule of values grouped by specification division rather than a full measured bill. Always follow the format the tender documents set.

Common BOQ mistakes

• Vague descriptions. "Brickwork" without size, type, mortar or location invites disputes.
• Mixing units. Measuring the same item in m2 in one section and m in another.
• Missing items. Lintels, cavity closers, making good and waste disposal are often forgotten.
• Arithmetic errors. Always use formulas and check that the summary agrees with section subtotals.
• Underpriced preliminaries. Site management and scaffolding run for the whole programme; price them by time.
• Unclear tax. State whether rates exclude sales tax or VAT.

From BOQ to invoice

Once the job starts, your invoices should mirror the BOQ: same item references, same rates, with the quantity completed this period. That makes approval much faster. Our construction invoice guide covers retainage, materials on site and progress claims in more detail.

When it is time to bill against your BOQ, you can enter the items and rates in our free invoice generator and download a professional PDF invoice or quotation. It is free, with no sign-up required.