CO1: UNDERSTAND THE PRINCIPLES AND PROCEDURE FOR ESTIMATION
AND COSTING OF
CIVIL ENGINEERING WORKS
ESTIMATE
Before taking up any work for its execution, the owner or builder should have a thorough
knowledge about the volume of work that can be completed within the limits of his funds or
the probable cost that may be required to complete the proposed work. It is therefore necessary
to prepare the probable cost or estimate for the proposed work from its plan and specification.
Otherwise, it may so happen that the work has to be stopped before its completion due to the
shortage of funds or of materials. Besides the above, an estimate for any public construction
work is required to be prepared and submitted beforehand so that sanction of necessary funds
may be obtained from the authority concerned.
Thus an estimate for any construction work may be 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 drawings 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, the elevation and the sections through important
points, alongwith a detailed specification giving specific description of all workmanship,
properties and proportion of materials, are required.
Thus an Estimate is a calculation of the various items of an engineering works, so as to know
its approximate cost and the quantities of various materials required with the labour involved
for its satisfactory completion.
The computation involved in arriving at the above details is called Estimating.
The accuracy of the estimate depends on the skill and experience of the Estimator. But the
actual cost of construction can be known from the physical measurements of the dimensions
for various items of works at site and the actual rates of all such items of works during execution
of the work.
in general, all estimates are approximate in nature and the difference between the estimated
cost and actual cost is a vital issue, which must be minimum.
PURPOSE OF ESTIMATING:-
Estimate for a work or project is necessary mainly for the following purposes :-
(1) To ascertain the necessary amount of money required by the owner to complete the proposed
work. For public construction works, estimates are required in order to obtain administrative
approval, allotment of funds and technical sanction.
(2) To ascertain quantities of materials required in order, programme their timely procurement.
To procure controlled materials, if any, like cement, steel, etc., quantities of such materials are
worked out from the estimate of the work and attached with the application for verification.
(3) To calculate the number of different categories of workers that are to be employed to
complete the work within the scheduled time of completion.
(4) To assess the requirements of Tools, Plants and equipment required to complete the work
according to the programme.
(5) To fix up the completion period from the volume of works involved in the estimate.
, (6) To draw up a construction schedule and programme and also to arrange the funds required
according to the programming.
(7) To justify the investment from benefit cost ratio. (For ideal investment, this ratio should be
more than one).
(8) To invite tenders and prepare bills for payment.
(9) An estimate for an existing property is required for valuation
ADMINISTRATIVE APPROVAL :- For every work (excluding petty works and repairs) it
is necessary to obtain, in the first instances the concurrence of the competent authority of the
administrative department requiring the work. The formal acceptance of the proposals by that
authority is termed "administrative approval" of the work. It is the duty of the engineering
department requiring the work by the administration to obtain the requisite approval to it. An
approximate estimate and such preliminary plans as are necessary to explain the proposals are
submitted by an engineering department to the administration to obtain ad- ministrative
approval to take up the work within the sanctioned amount. After receiving the administrative
approval detailed drawings, design and the estimated cost etc.. are prepared by the engineeing
department (Keeping the estimated cost within the administrative approval) and submitted to
the administrative department for sanction
TECHNICAL SANCTION - After receipt of administrative approval and expenditure
sanction a detailed estimate is further sanctioned by a competent technical authority of the
engineering department empowered by the Government (according to amount of the estimate),
which ensures that the proposals are structurally sound, and the estimate is accurately
calculated based on adequate data. Such sanction is known technical sanction and should be
taken before inviting tenders to execute the work
BUDGET PROVISION: Allocation of funds for specific expenses within a project or
business.
DIFFERENT TYPES OF ESTIMATES
Detailed Estimate
This includes the detailed particulars for the quantities, rates and costs of all the items involved
for satisfactory completion of a project.
Quantities of all items of work are calculated from their respective dimensions on the drawings
on a measurement sheet. Multiplying these quantities by their respective rates in a separate
sheet, the cost of all items of work are worked out individually and then summarised, ie..
abstracted (which is the detailed actual estimated cost of work). All other expenses required for
satisfactory completion of the project are added to the above cost to frame the total of a detailed
estimate. This is the best and most accurate estimate that can be prepared.
A detailed estimate 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. Such a detailed estimate is prepared for technical
sanction, administrative approval and also for the execution of a contract with the contractor.
A 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
AND COSTING OF
CIVIL ENGINEERING WORKS
ESTIMATE
Before taking up any work for its execution, the owner or builder should have a thorough
knowledge about the volume of work that can be completed within the limits of his funds or
the probable cost that may be required to complete the proposed work. It is therefore necessary
to prepare the probable cost or estimate for the proposed work from its plan and specification.
Otherwise, it may so happen that the work has to be stopped before its completion due to the
shortage of funds or of materials. Besides the above, an estimate for any public construction
work is required to be prepared and submitted beforehand so that sanction of necessary funds
may be obtained from the authority concerned.
Thus an estimate for any construction work may be 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 drawings 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, the elevation and the sections through important
points, alongwith a detailed specification giving specific description of all workmanship,
properties and proportion of materials, are required.
Thus an Estimate is a calculation of the various items of an engineering works, so as to know
its approximate cost and the quantities of various materials required with the labour involved
for its satisfactory completion.
The computation involved in arriving at the above details is called Estimating.
The accuracy of the estimate depends on the skill and experience of the Estimator. But the
actual cost of construction can be known from the physical measurements of the dimensions
for various items of works at site and the actual rates of all such items of works during execution
of the work.
in general, all estimates are approximate in nature and the difference between the estimated
cost and actual cost is a vital issue, which must be minimum.
PURPOSE OF ESTIMATING:-
Estimate for a work or project is necessary mainly for the following purposes :-
(1) To ascertain the necessary amount of money required by the owner to complete the proposed
work. For public construction works, estimates are required in order to obtain administrative
approval, allotment of funds and technical sanction.
(2) To ascertain quantities of materials required in order, programme their timely procurement.
To procure controlled materials, if any, like cement, steel, etc., quantities of such materials are
worked out from the estimate of the work and attached with the application for verification.
(3) To calculate the number of different categories of workers that are to be employed to
complete the work within the scheduled time of completion.
(4) To assess the requirements of Tools, Plants and equipment required to complete the work
according to the programme.
(5) To fix up the completion period from the volume of works involved in the estimate.
, (6) To draw up a construction schedule and programme and also to arrange the funds required
according to the programming.
(7) To justify the investment from benefit cost ratio. (For ideal investment, this ratio should be
more than one).
(8) To invite tenders and prepare bills for payment.
(9) An estimate for an existing property is required for valuation
ADMINISTRATIVE APPROVAL :- For every work (excluding petty works and repairs) it
is necessary to obtain, in the first instances the concurrence of the competent authority of the
administrative department requiring the work. The formal acceptance of the proposals by that
authority is termed "administrative approval" of the work. It is the duty of the engineering
department requiring the work by the administration to obtain the requisite approval to it. An
approximate estimate and such preliminary plans as are necessary to explain the proposals are
submitted by an engineering department to the administration to obtain ad- ministrative
approval to take up the work within the sanctioned amount. After receiving the administrative
approval detailed drawings, design and the estimated cost etc.. are prepared by the engineeing
department (Keeping the estimated cost within the administrative approval) and submitted to
the administrative department for sanction
TECHNICAL SANCTION - After receipt of administrative approval and expenditure
sanction a detailed estimate is further sanctioned by a competent technical authority of the
engineering department empowered by the Government (according to amount of the estimate),
which ensures that the proposals are structurally sound, and the estimate is accurately
calculated based on adequate data. Such sanction is known technical sanction and should be
taken before inviting tenders to execute the work
BUDGET PROVISION: Allocation of funds for specific expenses within a project or
business.
DIFFERENT TYPES OF ESTIMATES
Detailed Estimate
This includes the detailed particulars for the quantities, rates and costs of all the items involved
for satisfactory completion of a project.
Quantities of all items of work are calculated from their respective dimensions on the drawings
on a measurement sheet. Multiplying these quantities by their respective rates in a separate
sheet, the cost of all items of work are worked out individually and then summarised, ie..
abstracted (which is the detailed actual estimated cost of work). All other expenses required for
satisfactory completion of the project are added to the above cost to frame the total of a detailed
estimate. This is the best and most accurate estimate that can be prepared.
A detailed estimate 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. Such a detailed estimate is prepared for technical
sanction, administrative approval and also for the execution of a contract with the contractor.
A 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
