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Bill of Quantities Definition

A Bill Of Quantities (BOQ) is a standard document used during the tendering process in the construction industry. It is formulated by Quantity Surveyors based on the plans and specifications of a project.

It enables those bidding on the project to price with precision. There are several types of BOQ including approximate, notional and provisional.


A bill of quantities, or BoQ, is a document generally prepared by a cost consultant (quantity surveyor) for construction projects. The document provides project-specific measured quantities for items identified in drawings and specifications. Its primary purpose is to enable bidding contractors to accurately price the cost of construction on the basis of unified quantities. The meticulous measurement and costing within a BoQ minimise miscalculations that can lead to budget overruns and scope gaps, and aids project control.

It also serves as a guide for suppliers to prepare their tenders. By providing a complete breakdown of the works and materials required, the BOQ enables suppliers to compare their offers with others and determine which bids offer good value. The information contained in a BOQ can be used throughout the construction process, including progress tracking and valuation of variation claims.

The key elements of a BoQ are; Work Sections (representing likely sub-contract packages); Quantity Breakdown; Method of Measurement (counting units such as volume, length, area, number and weight), Unit Prices (materials and labour rates) and a Schedule of Rates. The BoQ can be drafted in different formats depending on the client and project requirements, such as; elemental, trade, activity, annotated and provisional.

In design-bid-build projects, a BOQ is often included as part of the tender package for contractors. It allows them to skip the process of conducting their own quantity takeoff, and can reduce the tender documentation period by several weeks.


Bill of Quantities (BoQ) is a document compiled by the quantity surveyor (employer’s consultant) from construction information provided in the design team’s drawings and specifications. It enables all contractors tendering for a contract to price on the same basis, which results in fairer and more accurate pricing. It is also used for post-tender works such as material scheduling, construction planning and cost analysis.

Among its many uses, the bill of quantities is particularly useful for estimating construction costs before breaking ground. It helps to minimise miscalculations that can lead to budget overruns and scope gaps. It also provides an excellent platform for comparing contractor prices.

A well-drafted BoQ can save contractors a significant amount of time during the tender process by eliminating rework and errors. This saves valuable time, enabling them to submit more competitive bids and win more contracts. It can also reduce labour costs and prevent costly project delays.

The precise measurements and calculations contained within the bill of quantities also reduce the risk of error during construction. This ensures that the final product will be of a high standard and can help avoid claims for variations.

A BoQ can be either firm or approximate, depending on the state of the design and construction. A firm BoQ will contain accurate measurements and is usually completed after the design has been finalised. An approximate BoQ, on the other hand, is an estimate that will be subject to re-measurement during construction.


A bill of quantities is a list of all materials and services required to construct a building or other structure. It is usually prepared by the engineer or architect after the project design has been completed. It is often included in the contract documentation as a means of giving contractors and suppliers a standard document against which to tender for the work.

A good bill of quantities should be based on accurate drawings and specifications. It should also be readable and easily accessible. It should also provide details of the different rates and scopes that are available in the market for the construction works. This will mitigate confusion and conflict during the tendering process.

Ideally, a fully detailed bill of quantities should be prepared before the construction begins. However, this is not always possible for smaller projects or alteration work. A provisional sum or approximate bill of quantities can be used instead. This will enable the contractor to price the work on the basis of the information provided, without having to wait until the final design is complete to measure.

The benefits of a well-prepared bill of quantities are numerous. They make it easier for contractors to compare bids in detail, and help ensure that the project budget is maintained throughout the process. It also helps reduce misunderstandings, favouritism, and human error in the estimating process. It is a vital tool for any construction project, and should be used with a professional quantity surveyor or civil engineer to avoid costly errors.


In the construction industry, a bill of quantities (BOQ) is a document used to provide tenderers with a detailed and accurate picture of what they need to bid on. It is typically prepared by a quantity surveyor and serves as the basis for the calculation of project costs. The BOQ will also detail the terms and conditions of the contract.

A BOQ is one of the first documents to be provided to potential contractors as part of the tender process. It includes a list of all materials, parts and labour required to carry out the work identified in the project drawings and specification. It is often divided into appropriate building elements or grouped in order of the work sequence that will take place on site. This allows the contractor to price individual items in a logical and efficient manner.

The cost consultant or quantity surveyor is usually associated with the design firm that is responsible for the project’s engineering. However, it is possible to prepare a BOQ with the help of a separate cost consultancy. This can be beneficial for projects where the client is unable to provide a clear description of the works involved in the project.

When preparing a BOQ, the cost consultant should follow a standard methodology to avoid any ambiguities or misinterpretation of the information contained in the document. This will also help to ensure that the tenderers are pricing the same elements of the work in a comparable way. This will reduce the time and expense involved in comparing tender prices and eliminating any rework or unnecessary expenses.