Estimation -----1

Estimating is the technique of computing the various quantities and the expected expenditure to be incurred on a particular work or project.

In case the funds are less than the estimated cost, the work is done in partially or by reducing it or specifications are altered, the following requirement are necessary for preparing an estimate.
a ) Drawings like plans, elevations and sections of important points.
b) Detailed specifications about workmanship & properties of materials etc.
c) Standard schedule of rates of the current year.

NEED FOR ESTIMATION AND COSTING:
1. Estimate gives an idea of the cost of the work and hence its feasibility can be determined i.e. whether the project could be taken up with in the funds available
2. Estimate gives an idea of time required for the completion of the work.
3. Estimate is required to invite the tenders and to arrange contract.
4. Estimate is also required to control the expenditure during the execution of work.
5. Estimate decides whether the proposed plan matches the funds available or not.