Using a bill of quantities improves the accuracy of proposals from contractors. It is a cost estimate of a construction project and includes rates for materials, equipment, labor, overheads, and profit.
It is usually prepared by a Quantity Surveyor and based on measurements taken from drawings in accordance with a measurement method. It is subsequently priced by contractors and used for pricing, valuation of variations and project control.
What is a Bill of Quantities?
A bill of quantities (BoQ) is a document used to describe the construction work and materials required on a project. It is prepared by the quantity surveyor, employer’s consultant, with the assistance of the design team, and is provided to tenderers as a standardised document against which they can price their tender. This ensures that all contractors are pricing the same amount of work, ensuring a fair and accurate tender process. The BoQ also provides a schedule of rates which can be used to assist with the valuation of variations and preparation of the final account.
The BoQ is normally prepared by using the process of taking off, where elements of the project are identified and measured based on the drawings and specifications. The BoQ is then broken down into work sections which reflect likely subcontractor packages. This makes it easier for suppliers to prepare their quotes.
The BoQ also includes an item for contingency sum which refers to unforeseeable costs that are likely to occur during the construction process. By including this, it enables you to budget for the unexpected and stay on track with the project. A well-prepared BoQ can eliminate unwanted rework, reduce project costs and lead to more successful bids.
Why Use a Bill of Quantities?
A bill of quantities is required for any type of construction project – from building renovations to road constructions. The process may differ slightly depending on the size and scale of the build. However, the basic principles remain the same – our team of quantity surveyors are well-equipped to handle any project and prepare an effective Bill of Quantities.
During the tender process, a Bill of Quantities will help to make the selection of contractors fairer by ensuring that all bidding companies are pricing the same work and items. This also allows you to easily compare the quotes from multiple contractors in detail.
Once the construction is underway, a Bill of Quantities will also help to ensure that you are paying your contractor for the correct work completed and not something else. It will also help to avoid costly disputes that arise from different interpretations of pricing and quantities by providing a clear description of the work being carried out.
The meticulous measurement and costing within a Bill of Quantities minimises miscalculations and budget overruns, helping to keep your project on track. Additionally, it is an essential tool to use during the design phase for accurate pricing and planning. It is also useful during construction by assisting with progress claims and providing a basis for valuing variations.
How to Use a Bill of Quantities
A bill of quantities is a tender document used in construction to provide detailed information on the work required for a project. It contains a description of the work, together with quantities measured from drawings in accordance with a standard measurement code. It is typically produced by a Quantity Surveyor and is subsequently used by contractors to price the work for which they are tendering.
A Bill of Quantities helps to eliminate misunderstandings and mistakes by clearly defining the work. It also allows for a more accurate comparison of contractor proposals, as all bids will be pricing on the same set of information.
To prepare a Bill of Quantities, start by identifying all the elements of the works. This can be done by reviewing the architect’s plans and using a process called “taking off”. Once all the elements of the work have been identified, write a list of each item, together with the unit of measurement (for example, concrete is written as “CUM”). Add in a contingency sum, which is an amount to cover unforeseeable costs.
Different parts of the works are usually completed by subcontractors, so the Bill of Quantities is often separated into work sections that reflect likely subcontract packages. This makes it easier for suppliers to get prices from their subcontractors and gives them a better chance of winning the contract.