Last edited 04 Sep 2020

Types of bill of quantities

1 Introduction
2 Firm bill of quantities
3 Approximate bill of quantities
4 Related articles on Designing Buildings Wiki

[edit] Introduction

A bill of quantities (sometimes referred to as a 'BoQ' or 'BQ') is a document, typically prepared by a cost consultant (often a quantity surveyor) that provides measured quantities of the items of work identified by the drawings and specifications in the tender documentation for a project. It is issued to tenderers for them to prepare a price for carrying out the works.

According to NRM2, RICS new rules of measurement, Detailed measurement for building work, there are two types of bill of quantities; firm and approximate.

[edit] Firm bill of quantities

A firm bill of quantities is used to obtain a lump-sum price for a fully-designed project. The work required is measured and described precisely, meaning that it can be priced accurately. As a result, tender prices should be reliable and good financial control should be possible. Where changes are necessary to the works described in the tender documents, the bill of quantities provides a good basis for assessing the costs of those changes.

[edit] Approximate bill of quantities

An approximate bill of quantities (sometimes referred to as a notional bill of quantities or provisional bill of quantities) is subject to re-measurement, and is used if there is insufficient information to prepare a firm bill of quantities at the tender stage, or if it is decided that a firm bill of quantities is not necessary.

The description of the works required is complete, but the quantities are approximate. As a result, quantified schedule of rates are provided by tenders rather than a lump-sum price, and the quantities are subject to re-measurement on completion.

This may appear an attractive option, as less cost and time is required to prepare the bill of quantities, however, typically, there will be more variations, and as re-measurement is required, overall administrative costs may be higher. In addition, there is greater cost uncertainty.

See also: Bill of quantities breakdown structures for descriptions of the three main breakdown structures for bills of quantities:

NB: An 'unpriced bill of quantities' (sometimes referred to as the tender pricing document) is the document issued to tenderers, who will then estimate their price for each item. The 'priced bill of quantities' constitutes the tenderer's offer and is the unpriced bill of quantities, but with the tenderer’s rates, costs and totals added.