Estimation and Specifications in Projects

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Questions and Answers

What is the total plinth area of the residential building project mentioned?

1500 sq.m.

Calculate the plinth area rate in sq.m. if the rate is given as 14915 per sq.ft.

Approx. $160,000 per sq.m.$

What percentage is added for water supply and sanitary installations to the building cost?

What is the total percentage of extra costs (architectural treatment, water supply, internal installations, electric & gas services) added to the initial building cost?

42.5% Signup and view all the answers

Define 'taking out of quantities' in the context of a detailed estimate.

It refers to calculating the quantities for each item from the drawings as accurately as possible. Signup and view all the answers

What documentation is usually submitted with the detailed estimate to obtain Technical Sanction?

A report explaining the project's history, necessity, scope, and main features. Signup and view all the answers

What is the purpose of including a contingency percentage in a detailed estimate?

To allow for unforeseen items or expenditures. Signup and view all the answers

What is meant by 'Bill of Quantities' in the context of estimations?

It is a document that lists all items of work and their estimated quantities for costing. Signup and view all the answers

What is the purpose of the abstract of cost in estimation?

The abstract of cost shows the total quantities under each sub-head, rate per unit of measurement, and total cost. Signup and view all the answers

Explain the difference between a contractor estimate and an engineer's estimate.

A contractor estimate is prepared by the contractor to determine bid prices, while an engineer's estimate is for financing and checking bids. Signup and view all the answers

What are progress estimates and when are they typically made?

Progress estimates are made by the engineer at regular intervals to determine amounts of partial payments to the contractor, commonly on a monthly basis. Signup and view all the answers

What is the significance of junctions and corners in detailed estimating?

Junctions and corners require special attention as they can affect the accuracy of measurements and quantity calculations. Signup and view all the answers

Define the separate or individual wall method in estimating.

The separate or individual wall method involves measuring lengths of long walls 'out-to-out' and short walls 'in-to-in' for accurate quantity calculations. Signup and view all the answers

How does the center line method differ from the separate or individual walls method?

The center line method estimates symmetrical footings by considering the central alignment of walls, while the individual wall method measures walls separately. Signup and view all the answers

Why is accuracy in calculations important for detailed estimates?

Accuracy in calculations ensures that all parts of the building are accounted for without omissions, affecting cost and project management. Signup and view all the answers

What are the typical components included in the detailed estimate calculations?

Typical components include lengths, breadth, height of walls, excavation volumes, and material quantities for concrete, masonry, and foundations. Signup and view all the answers

Study Notes

Estimation and Specifications

Estimation involves calculating project costs.
Specifications outline detailed project requirements.
Rough cost estimates are initial approximations.
Detailed estimates refine calculations after design finalization.
Detailed estimates correct errors from rough estimates.
Detailed estimates provide technical sanction.
Project breakdown into work items or activities occurs.
Quantities of each item calculated from drawings.
Method called "taking out of quantities" used.
Bill of Quantities document for itemized quantities.
Itemized work units based on local practice.
Itemized work multiplied by estimated current rate.
Total of all items equals estimated total cost.

Example 2

Rough cost estimate for a residential building.
Total plinth area: 1500 sq. m.
Plinth area rate: 14915/ sq. ft.
Special architectural treatment: 1.5% of building cost.
Water supply and sanitary installations: 5% of building cost.
Internal Installations: 14% of building cost.
Electric and gas services: 16% of building cost.
Contingencies: 3% overall.
Supervision charges: 8% overall.
Design charges: 2% overall.

Detailed Estimate

Detailed estimates calculate costs meticulously using detailed working drawings.
Rough estimate errors are avoided.
Detailed estimates submitted for technical sanction.

Bill of Quantities

Document showing itemized work amounts.
Measurements (length, breadth, height) recorded on the document.
Corresponding quantities calculated and recorded.
Remarks section available on the document.

Priced Bill of Quantities

Lists quantities, unit costs, and total costs for each item.
Itemized description of each item.
Unit costs recorded and calculated.
Total cost per item is determined.
Remarks section available on the document.

Additional Information

Rates usually match local Schedule of Rates.
Premium allowed for rising labor/material costs.
Additional 5% for possible contingencies (beyond unforeseen items).
2% for establishment charges.
Drawings and details included in the submittal.

Types of Detailed Estimates

Contractor Estimate: Created by contractor for bidding.
Engineer's Estimate: Prepared by engineers for financial purposes.
Progress Estimate: Regularly prepared to measure project completion and payments.
Monthly estimate, a type of progress estimate.

Methods of Detailed Estimate

Measuring dimensions (length, breath, height) from drawings.
Special attention to wall junctions.
Symmetrical footings: calculated using two methods.
Separate or individual wall method.
Center line method.

Separate or Individual Walls Method

"Long walls" run in one direction, "short walls" run perpendicularly.
Lengths measured according to "out-to-out" or "in-to-in."
Wall lengths multiplied by breath and height to obtain quantities.
Useful for calculating excavation, concrete, brickwork.

Separate or Individual Walls Method (Continued)

Center-to-center lengths used for symmetrical footings.
"Out-to-out" length (long walls) = center-to-center length + ½ breadth on each side.
"In-to-in" length (short walls)= center-to-center length - 1 breadth.

Methods of quicker estimation for long walls

Length of foundation trench measured ("out-to-out").
Foundation concrete length the same as foundation trench.
For each footing, preceding footing length minus two offsets.

Methods of quicker estimation for short walls

Same as long wall method but offsets added.

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Description

This quiz covers the fundamental concepts of estimation and specifications in project management. It includes topics such as rough and detailed cost estimates, project breakdown, and methods for calculating quantities. Test your understanding of how to effectively estimate project costs and outline specifications.