What is Estimate and terms used in estimation


Royal Member
It is defined as the process of calculating the quantities and costs of the various items required in connection with the work. It is prepared by calculating the quantities, from the dimensions on the drawing for the various items required to complete the project and multiplied by unit cost of the item concerned. To prepare an estimate ,drawings consisting of the plan , elevation and the sections through important points, along with a detailed specification giving specific description of all workmanship , properties and proportion of materials , are required.

Detailed estimate
It includes detailed particulars for the quantities, rates and costs of all the items involved for satisfactory completion of a project. Detailed estimates is accompanied by
(a) Report
(b) Specifications
(c) Detailed drawings showing plans, different sections, key or index plan .etc,
(d) Design data and calculations
(e) Basis of rates adopted in the estimate .

Preliminary or approximate or rough estimate
This is an approximate estimate to find out an approximate cost in a short time and thus enables the authority concerned to consider the financial aspect of the scheme.

Bill of quantities
The purpose of the Bill of quantities is to provide a complete list of quantities necessary for the completion of any engineering project and when priced gives the estimated cost of the project.

Revised estimate
A revised estimate is a detailed estimate for the for the revised quantities and rates of items of works originally provided in the estimate. Without material of a structural nature from the design originally approved for a project.

Supplementary estimate
While a work is in progress, some changes or additional works due to material deviation of a structural nature from the design originally approved may be thought necessary for the development of a project. An estimate is then prepared to include all such works is known as supplementary estimate.

Complete estimate
this is an estimated cost of all items which are related to the work in addition to the main contract or to the detailed estimate.
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