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How to Prepare a Bill of Quantities

A bill of quantities (BoQ) is an estimate of construction costs, prepared by a cost consultant or quantity surveyor. It provides project-specific measured quantities for items identified in drawings and technical specifications.

It allows all contractors tendering for the contract to price on the same information. This reduces misunderstandings and disputes.

Cost Estimation

The preparation of a cost estimate is a crucial part of any construction project. It requires a skilled quantity surveyor (QS) to use specialized software to measure the different aspects of the project, compile the labor and material items and then prepare a detailed yet precise description. These are incorporated into the bill of quantities document which is a vital construction contract document. It is used by many different parties during the construction process to monitor and control costs.

The estimating process is done using a construction cost management system that incorporates the latest software. It allows for more accurate estimates and is also a useful tool for budgeting, construction time forecasting and cash flow forecasting. A QS can also provide value engineering services and cost savings for the client.

Generally, the bill of quantities is prepared after the design has been completed and a specification made. It must be developed according to a standard methodology to avoid any misunderstandings or errors. The preparation of a BOM is based on reviewing the drawings and specifications to identify all work, materials and quantities required. It also takes into account any specific technical requirements or any other work not covered by the plans and specifications.

The estimating process involves multiplying the total quantity of each item by its unit rate. The result is the partial cost for each job or section. It is a common practice to add a margin for contingencies and profits, which are usually included in the final estimate. It is also important to consider the cost of materials and any other associated costs, such as delivery charges and overheads.

Taking Off

The taking off process is the first step in preparing a construction bill of quantities (BoQ). It involves measuring dimensions and compiling descriptions from the plans and specifications. The resulting list is then used to create a list of work items that can be priced by different contractors.

The BoQ is a critical document in the tendering process, and it allows contractors to compare costs with each other before making their final decision. It’s also a good way to ensure that the contractor’s quote is accurate and comprehensive. In addition, a detailed BoQ can help prevent the contractor from using substandard materials or overestimating the cost of certain tasks.

While many cost estimators may perform a takeoff on their own, the preparation of the bill of quantities is usually done by a quantity surveyor or engineer. The method of preparing a BoQ varies from one project to the next, but typically it follows a standard methodology. This can be achieved through the use of software packages that simplify the process.

Once the taking off process is complete, the contractor can then prepare a bid for the project. The BoQ will provide them with a full description of the work to be carried out, as well as the amount of materials and labour required. The cost estimate will also include any unforeseen expenses that may arise during the construction process.

Taking Measurements

The taking measurements process is a crucial part of creating a bill of quantities. The quantities must be measured precisely to avoid any misinterpretations, especially when it comes to materials. If the quantities are incorrect, it can cause a lot of problems for the construction project. This is why it is advisable to follow a standard methodology while preparing a BOQ. This will reduce the chances of making mistakes and save time as well.

A Bill of Quantities (BOQ) is a document that contains a list of the construction materials and labor needed for a specific project. It is generally prepared by a quantity surveyor or cost consultant, and is used as a basis for tenders. It allows contractors to easily compare their proposals and choose the best one. It also ensures that all contractors are quoting the same materials and labor rates, which is important for project success.

It is often easier to prepare a BOQ when it is divided into work sections that reflect likely subcontract packages. This makes it easier for suppliers to obtain prices from subcontractors and provides a more accurate pricing document.

A BOQ is an essential tool for any construction project. It helps to ensure that all projects are carried out within budget and schedule, and that all the required materials are available when they are needed. It is also a good way to track the progress of a construction project and prepare for future payment applications.


A bill of quantities (BOQ) is a list of construction materials and labor required to complete a project. It can be prepared by a quantity surveyor or cost consultant and issued to tendering contractors to help them determine a price for the works. A BOQ is a valuable tool for the tendering process and it lays out an accurate and fair system of pricing.

A boq should be prepared according to a standard methodology. This will minimize errors and ensure that the project is completed on time. It should also include itemized items and unit prices. It should be reviewed and vetted by the client, engineer, and design team to ensure that it is complete and accurate. It should also be updated as changes are made to the project.

The drafting and preparation of a boq is a time-consuming process, but it can save the project a lot of money. It will also minimize the risk of disputes, claims, and delays. It will also allow the contractor to make accurate estimates of work costs.

The preparation of a boq is a complex and detailed process, but it can be done using a variety of software tools. These include building information modeling (BIM) systems, which can automatically produce a boq from the information contained within the model. In addition, there are many companies that specialize in preparing boqs.