What is a bill of quantities item?

The smallest priceable part of a bill of quantities

A bill of quantities item describes a defined piece of construction work that can be assigned a unit and quantity. It is the level at which a contractor enters a rate in the bill of quantities. The same item can then support tender comparison, the contract, progress measurement and valuation.

An item is more than a line of text. It establishes a shared basis for scope and price. The clearer it is, the less room there is for the client and contractor to make different assumptions.

Components of a well-written item

• item or reference number
• clear short description and, where required, full description
• material, quality, dimensions and workmanship where relevant
• scope, including significant ancillary operations
• appropriate unit, such as m, m², m³, kg, item or hour
• forecast or measured quantity
• rate and calculated item total
• clear interface with adjacent items

A worked example

Item: “Construct 125 mm metal-stud plasterboard partition, double boarded both sides, including framing and perimeter junctions.” Unit: m². Quantity: 85. Rate: CHF 148. The item total is 85 × CHF 148 = CHF 12,580. If the measured quantity changes, the agreed rate remains the valuation basis unless the contract or item states otherwise.

Standard and free-text items

An item from the Swiss NPK catalogue follows a standard structure and vocabulary. That supports consistent descriptions and digital exchange, but the selected characteristics must still suit the project.

A free-text item is written specifically for the work. It is useful where no suitable standard item exists or where a contractor offers a defined package. Free wording does not justify vague wording: scope, quality and pricing basis must be equally clear.

Items, headings and preliminaries

Headings organise the bill but do not normally receive a quantity or rate. Preliminaries and general notes state conditions that apply across several items. The BQ item contains the priceable work itself. Hiding significant work only in a general note makes estimating and later valuation unnecessarily uncertain.

From tender to final valuation

1. The item is described and given a forecast quantity.
2. The tenderer builds a rate from labour, materials, plant, subcontract work and allowances.
3. Following award, the item becomes part of the agreed scope.
4. Progress and the actual quantity are recorded during construction.
5. Quantity changes or altered work are assessed transparently.
6. The accepted quantity and rate form the basis of valuation.

Common errors

Vague composite items, inappropriate units and omitted ancillary work quickly produce bids that cannot be compared. “Item” or “lump sum” should be used deliberately, not to hide an unresolved scope. The description and the rate must always refer to the same work.

Work items in Caturix

Caturix structures quotation items with a description, unit, quantity and price. Standardised Swiss NPK items and project-specific free text can be used to suit the job. Once a quotation is accepted, the items remain connected to the project process, from preliminary costing to site reporting.

Frequently asked questions

What information should a BQ item contain?

At minimum, a clear description, an appropriate unit and the forecast quantity. A priced bill also includes the rate and item total. Material, dimensions, workmanship, inclusions and interfaces should be stated whenever they affect scope or price.

What is the difference between an NPK item and a free-text item?

An NPK item follows the standardised Swiss NPK catalogue. A free-text item is written specifically for the project. Either can form a valid BQ item when the scope, unit and pricing basis are unambiguous.

Can one item include several operations?

Yes, if they form a coherent piece of work that can be priced and measured reliably. Combining unrelated operations in one item makes tender comparison, measurement and variations harder, so separation is usually better.

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