Q.1) Explain the estimated cost is never the actual cost.
The word ‘estimate’ itself refers that it can never be actual. An estimate is a probable cost of construction for a work.
The accuracy of an estimate depends on a careful study of the various dimensions on the drawings, the method of estimating, consideration of rates, probable expenses which may be required for various unforeseen works and laborers and also quantity of tolerance for wastage.
Also the actual cost depends upon the skill and experience of the estimator. But the actual cost can be known from the physical measurements of the dimensions for various items of work at site and the actual rates of all such items of work during execution of work.
All expenses for all probabilities can be known when the construction is completed. Day-to-day expenditure is maintained by the completion of the work as well as the account.
So, it can be justified that whatever method may be adopted, in general, all estimates are approximate in nature and can never be the actual cost of work.
Q.2) What is the principle of unit of measurement?
The units of measurements are mainly categorized for their nature, shape, size and for making payments to the contractor also. The principle of units of measurements normally consists the following:
- Single units work i.e., piecework and job work like doors, windows, trusses etc., are expressed in numbers.
- Long and thin work consisting linear measurement like cornice, fencing, hand rail, bands of specified width etc., are expressed in running meters (rm)
- Shallow, thin and surface work consisting areal surface measurements like plastering, white washing, partitions of specified thickness etc. are expressed in square meters (m²).
- Mass, voluminous and thick work consisting cubical contents which involve volume like earth work, cement concrete, masonry etc. are expressed in cubic meters.
Q.3) List out the data required for preparing an estimate.
The data required for preparing an estimate are given below.
i) Drawings t.e., Plans, elevations, sections, etc
IV) Methods of measurement
Drawings are required for the calculation of the quantities of the materials The drawings showing plans, elevations, different section and other relevant detail with clear and complete dimensions are very essential before preparing an estimate.
Specification describes the nature and class of the work, material to be used, workmanship and is very important for execution of work.
- General Specifications
This gives a general idea about the nature, quality, class and materials in general terms to be used in various types of work.
- Detailed Specifications
These gives the detailed description of the various items of work laying down the quantities and qualities of materials, their proportions, method of preparation, workmanship and execution of work.
Rates are essential for the computation of estimate by multiplying quantities of materials with unit rates. For preparing the estimate the unit rates of each item of work are required.
Q.4) Define estimated cost and actual cost. What is the purpose of estimating?
Estimated cost is the anticipated or probable cost of the work and is usually prepared before the construction is taken up.
Actual cost is the cost which is known only after the completion of the work from the account of the completed work.
Purpose of Estimating
- To estimate probable cost of the work.com
- To find the various types and quantities of material required.
- To find the various categories and quantities of labours required.
- To give an idea of time required for the completion of the work.
- To invite the tenders and quotations and to arrange contract.
- To control the expenditure during the execution of work.
- To justify investment from benefit cost ratio.
- To help in fixation of standard rent and valuation of properties.
Q.5) Define estimate. Write its importance.
Estimate is the process of calculating or computing the various quantities and the expected expenditure to be incurred on a particular work or project. The estimate gives the probable cost of the work.
The primary objective of an estimate is to enable one to know the probable cost of the work before the completion of the project. If the estimate is prepared carefully and correctly there will not be much difference between estimated and actual cost.
Importance of Estimating
- The estimate is necessary for fixing budget for the purposed project.
- It is necessary for calculating the required quantities of materials labours for the project.
- It is necessary to draw up a work schedule
- It is necessary to fix up a complection period of the proposed project.
- It is also helpful to check the works done by contractors during and after the execution.
- It is required for preparing tender for the project.
- It is necessary for the valuation of land and building.