Why produce Bills of Quantities?
BQ enables all Contractors tendering for a contract to price exactly on the same information Provides a basis for valuation of variations or changes to the works Can be used by the Contractor to assist in ordering of building materials and for assessing his labourrequirements Provides good basis for cost analysis for use on future contracts in Cost Planning Works, e.g. approximate estimating and setting cost targets for budgeting purposes.
Bill of Quantities (BQ)
Translate drawings, schedules, and specifications by architects and engineers into a document fully describing and accurately representing the quantity and quality of the works.
4 Stages Of BQ Preparation (Traditional)
Taking Off / Squaring / Abstracting / Billing
Taking Off
Taking off is a process of transferring the dimension scaled or read from the drawings to a specially ruled paper called the dimension paper.
Squaring
Squaring is a process of getting the total quantity whether in number, length, area or volume for each set of measurement in the dimension paper.
Abstracting
Abstracting is a process of transferring the squared dimensions to the abstract, where they are written in a recognized order under the appropriate work section headings and subsequently totaled and converted to the required units or billing as stated in the Standard Method of Measurement.
Billing
Billing is a process of rewriting all the items, including their quantities taken from the abstract for the whole project into the billing papers in a recognized format of a Bill of Quantities.
BQ Content
Bill of quantities must contain the basic information presented in a format that is easily understood.
Preliminaries
It explains the type and scope of works, the client’s needs, temporary site facilities, and other items affecting the implementation of the works. Items involved need not be measured but need to be described in detail, and the contractor will have to price the items that will affect the cost of the works in a lump sum figure. Items in this section will not be incorporated into the works but are essential for the completion of the works. Specifications describe the quality of materials and workmanship of the works, which is usually not practical to be presented in the drawings, including other information necessary for the contractor to price the BQ.
Measured Quantities
Measured quantities are produced from the measurement of all the works measurable based on the approved Standard Method of Measurement document. These quantities shall be measured as accurately as possible so that no parties will make a loss during the implementation of works.
Provisional Quantities
Provisional quantities are produced similarly as above but it is for works which cannot be accurately measured at the time of preparation of bill of quantities. This situation happens due to incomplete information of work or in cases whereby the extent of work cannot be fully determined until the work is completed. Such work will be subjected to remeasurement after the works has been carried out.
Prime Cost Sum
A prime cost sum is included for work or services to be executed by a nominated subcontractor, a government, or a statutory authority or for material or goods to be supplied by a nominated supplier. Such a sum excludes the profit and attendance of the main contractor, of which provisions are made in the document for such inclusion by the contractor.
Provisional Sum
A provisional sum is included for work or for costs that cannot be entirely defined or detailed at the time the bill of quantities are prepared. Contingency Sum
A contingency sum is a sum allocated for any unforeseen work that cannot be determined at the time of bill of quantities preparation. It will be a saving to the client if such contingency sum is not expended due to no unforeseen work.
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