The prime purpose of the Bill of Quantities (BQ) is to enable all contractors tendering for a contract to price on exactly the same information. Subsequent to this, it is widely used for post-tender work such as: material scheduling; construction planning; cost analysis; and cost planning. Due to the re-work involved in the post-tender use of the BQ, the ‘extent of use’ of the BQ is important. The ‘re-work’ is any work such as; modification, or grouping, or breaking up of data when used for a particular task by a management group. The ‘extent of use’ is defined as the direct use, after subtracting the re-work from the total use. This paper identifies the contractor's current use of the BQ for post-tender work based on eight case studies, and establishes the ‘extent of use’ thus highlighting the re-working of the bill. By establishing the ‘extent of use’, the true picture of the direct use and the repetition work can be shown. The average extent of use of the BQ for post-tender work in the industry was found to be 50%. This 50% use of the BQ requires some form of re-working. This re-work needs to be reduced if improved post-tender use of estimating data is to be achieved. Information stored in the BQ should be arranged in a directly useable way. It was found that, ‘quantities’, ‘quantity units’, and ‘unit rates’ are the key elements of the BQ information that need to be presented in a more meaningful format if the amount of re-work is to be reduced.
BOQ shall be used in every phase (pre-contract & post-contract) of the project but need of BOQ differs based on different contract agreements & project. The major usages are listed below.
Parts of BOQ can be varied according to the project size as well the practices. Generally it has measured works, Preliminaries & Provisional sums. The contract sum would be addition of these three items.
In construction industry, preliminaries is known as the indirect cost for execution of project but these are the costs which is very much vital for the construction activities. The reason for these cost mentioned separately is it is very difficult to distribute these cost amongst with measured works. The examples for preliminaries listed below.
From the above mentioned examples, it can be understood these costs cannot be distributed to work item but without these expenses there will be no project.
It is the actual or estimated work will be carried out to complete the project. The works have been measured in different units. They are liner meter, square meter, cubic meter, number, item & etc. Value of measured works will be calculated by multiplication of quantities and rate.
It is the sum which is allocated for the undersigned works at the tender time. It will be adjusted after the execution of the project.
In summary BOQ is very much important for the commercial management purposes. It should be understood by every construction professional to deliver a quality and expected product to client. In other words to provide value for money.
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