Quantity surveying is a task of measuring construction work required to implement the architects’ design for new or renovated buildings. One purpose of quantity surveying is to produce a document of quantified sub-work items to represent the whole construction. It is known as Bills of Quantities.
Objectives of the Bill of Quantities
· to provide necessary information on the quantities of works to be carried out
· assist bids to be prepared efficiently and accurately;
and during the post-contract stage,
· use a priced Bill of Quantities for the preparation of interim valuation of works executed.
To attain these objectives,
· Separate entire construction work into different items in the Bill of Quantities. That means separated into sub activities, and when added together it represents the whole construction works.
· Sub activities or items are grouped under different classes of works or trades with sufficient details,
· It distinguishes works of the same nature but carried out in different locations
The layout and content of the Bill of Quantities must be simple and brief. It shall be consistent with the above requirements.
To produce a Bill of Quantity, a detailed quantity surveying process has to be completed. These services are provided by a professional Quantity Surveyor (QS).
- A Quantity Surveyor is usually hired by the Owner / Architect at the inception of a project.
- The QS makes;
- cost feasibility studies,
- establishes the construction budget,
- makes cost checks at all stages of the design process,
- prepares a final Bill of Quantities.
The Bill of Quantity is a part of the bidding document, especially in Measure and Pay contracts. The bidders use information in construction drawings, specifications, and the bill of quantity as the basis for pricing of the work.
- The QS advises the owner on contractual arrangements,
- compiles certificates of interim and final payment to the contractor doing the work.
Experienced Quantity Surveyors have a good knowledge of construction costs. Therefore, they can provide a design cost planning service even before actual design or construction begins. That helps the client to decide on their total budget, before the commissioning of any design work. If proper cost planning techniques are not used, it may result in costly bids.
SOME ADVANTAGES OF THE USE OF BILL OF QUANTITIES
- No need to measure the same design or the plan by several bidders to prepare their bids for competition. It saves cost and time.
- Bids submit by different bidders are consistent because all use the same bill of quantity for the preparation of their bids. Therefore at the selection stage, the client can select the most efficient and least expensive contractor for his job.
- Other than plans and specifications, the client can provide a broad and clear statement of the work he requires using the bill of quantity. And then the bidder can state the price at which he is prepared to undertake the job.
- It can be used as a basis for the financial administration of the contract.