Menu Close

How to Prepare a Bill of Quantities

A bill of quantities (BoQ) is an essential part of the construction tendering process. It allows contractors to bid on a specific project and compare their proposals. It should be prepared following a standard methodology that reduces the chances of mistakes.

This article will explore the various elements of BoQ namely; elemental, trade, activity, annotated and provisional bills. The article will also discuss the method of preparing these bills.

Units of Measurement

While preparing a bill of quantities, it is important to consider the units of measurement that will be used. Units of measurement are the individual measurements that will be taken on the site to identify the quantities of the various construction items. These measurements can be in the form of numbers (e.g door handles), lengths (e.g handrails, kerbs), areas (e.g floor tiles, plaster) or volumes (e.g concrete). When tenderers are asked to submit prices next to each measured quantity, they will do so based on the units of measurement listed in the BoQ. This avoids confusion and ambiguity between different tenderers, and ultimately reduces the likelihood of disputes occurring during construction.

Bills of quantities are generally prepared by a quantity surveyor or estimator, who will review the drawings and other relevant documents provided for the project. They will then prepare a list of all the elements of work required and quantify them. This process is known as ‘taking off’. Typically, BoQs are prepared in work sections that reflect likely sub-contract packages. This makes it easier for the supplier to obtain prices from their sub-contractors and is more likely to result in a competitive price.

It is also important to ensure that the BOQ is prepared using a standard methodology. This will eliminate any ambiguity and confusion in the document, and reduce the likelihood of disputes that may arise from different interpretations of pricing and quantities. In the UK, BOQs for general construction works were previously prepared according to SMM7, which was replaced by New Rules of Measurement on 1st July 2013.

Item Numbers

Item numbers in a bill of quantities are used to identify different components and the amount of each component needed. They can also be used to create balloons in assembly drawings, which correspond with the item numbers in the BOM. These balloons can be moved, edited, and split. The component details in the balloons display the custom properties that you defined in the Item Master (P4101) and Item Branch (P41026) programs, such as issue type code and lead time.

Bills of quantities are typically prepared by a Quantity Surveyor using construction drawings and specifications of a project. The document is then used by contractors to price their tenders. Using a bill of quantities reduces the tender documentation process and enables contractors to begin work as soon as possible.

There are many types of bills of quantities, including elemental, trade, activity, annotated and provisional. The most common is the standard bill of quantities, which is prepared according to a particular measurement method. This helps to prevent misunderstandings between parties. The standard bill of quantities may also include a contingency sum, which is a sum that covers unforeseeable costs that might be incurred during the project.

Item rates in a bill of quantities are the costs per unit that the contractor is required to pay for specific items and services. They are typically provided in the form of a free format rate sheet or a plug-rate list.


A bill of quantities is a document prepared by a cost consultant (such as a quantity surveyor) that contains general information about the project together with quantities measured from drawings in accordance with a measurement code. It can be used throughout the construction project for valuation and cost control purposes. It is also a key component of the tendering process.

Preparing a bill of quantities requires an in-depth knowledge of the design and a good understanding of the type of contract to be used. It is usually prepared during the early stages of a project and provides tenderers with the details they need to price the work. It can be created on a computer using software or by taking off from the drawings.

Once the quantities have been taken off and arranged in accordance with a standard arrangement, they are then described by a number of different categories. These descriptions help the contractor understand what is required of them in terms of materials and labour. This helps them to provide a competitive tender.

The description in a bill of quantities can be as simple or as detailed as the design allows. It can be grouped into the various elements of a build, such as walls or roofs, and it can be grouped into specific trades, such as electrical or plumbing. Some bills of quantities are also grouped into activities or operations based on network analysis, which means that one activity needs to be completed before the next can start. This method is often used on projects with tight timescales.


During the planning and design stage of a project, the bill of quantities is used to identify all elements of construction works. This document is typically prepared by a quantity surveyor (QS) and contains general information about the project, together with quantities measured from drawings in accordance with a measurement code. It is then subsequently priced by contractors for valuation and cost control purposes.

The item rates in a bill of quantities reflect the costs of materials, equipment, and labor. They also include a percentage for overhead and profit. These rates are then multiplied by the quantity to calculate the overall price of the work.

A Bill of Quantities can be prepared from a number of different sources. It can be a direct copy from an architect’s plans, or it may be based on a standard work breakdown structure such as CSI MasterFormat. This format makes it easier for contractors to price out the work.

It is important to prepare a thorough bill of quantities before the tendering process starts. This will ensure that all contractors are bidding on the same information and will help to prevent misunderstandings and disputes. The bill of quantities can then be used to prepare payment applications as the project progresses. This will make it easy for contractors to keep track of the amount of materials they have consumed, and it will also allow them to plan ahead for future cash flow requirements.