Que1.1. What’s estimation? What’s the purpose of estimation?
Answer Estimation It’s the process which guides us to determine the cost, volume, tools, shops and labours which are demanded to complete the design with in time of completion. Purpose of Estimation Following are the purposes of estimation
1. To give a nicely Accurate Idea of the Cost An estimate is necessary to give the proprietor a nicely accurate idea of the cost to help him decide whether the work can be accepted as proposed or not, depending upon the vacuity of finances.
2. Estimating Accoutrements From the estimate of a work it’s possible to determine what accoutrements ( and in what amounts) will be needed for the work so that arrangements to land them can be made.
3. Estimating Labour The number and kind of workers of different orders who’ll have to be employed to complete the work in the specified time can be set up out from the estimate.
4. Estimating Plant An estimate will help in determining the quantum and kind of outfit demanded to complete the work.
5. Estimating Time The estimate of a work and once experience enable one to estimate relatively nearly the length of time needed to complete an item of work or the work as a whole.
Que1.2. Describe the types of estimates.
Answer Types of Estimates Estimates can be grouped into two main orders Approximate Estimates An approximate estimate is an approximate or rough estimate prepared to gain an approximate cost in a short time.
Detailed Estimates
1. A detailed estimate of the cost of a design is prepared by determining the amounts and costs of everything that a contractor is needed to give and do for the satisfactory completion of the work.
2. It’s the stylish and most dependable form of estimate.
3. A detailed estimate may be prepared in the following two ways Unit- volume Method
a. In the unit- volume system, the work is divided into as numerous operations or particulars as are needed.
b. A unit of dimension is decided.
c. The total volume of work under each item is taken out in the proper unit of dimension.
d. The total cost per unit volume of each item is analysed and worked out.
e. also the total cost for the item is set up by multiplying the cost per unit volume by the number of units.
f. This system has the advantage that the unit costs on colorful jobs can be readily compared and that the total estimate can fluently be corrected for variations in amounts.
ii. Total- volume Method In this system, an item of work is divided into the following five services Accoutrements,
b. Labour,
c. Plant,
d. Charges, and
e. Profit.
The total amounts of each kind or class of material or labour are set up and multiplied by their individual unit cost. also, the cost of factory, outflow charges and profit are determined.
Que1.3. What are the main way in medication of estimate?
Answer Following are the way in the medication of an estimate
1. Taking Out Amounts
i. In the first step of taking out amounts, the measures are taken out from the delineations and entered on dimension distance or dimension paper.
ii. The measures to be taken out would depend upon the unit of dimension.
For illustration, in the case of gravestone masonry length, consistence and height of the walls would be entered on the dimension distance, whereas, in the case of publishing only the lengths and height of the walls would be entered.
2. Squaring Out The alternate step consists of working out volumes, areas and so on, and casting up their total in recognised units.
3. Abstracting
i. In the third step, all particulars along with the net results attained in the alternate step are transferred from dimension wastes to especially ruled wastes having rate column ready for pricing.
ii. The alternate and third way over are known as ‘ working up ’. All computations in these stages and every entry transferred should be checked by another person to insure that no fine or copying error occurs.
Que1.4. What are the principles of deciding unit of dimension?
Answer Following are the principles of selection of unit of dimension 1. The unit of dimension should be simple and accessible to measure, record and understand.
2. It should be one which provides for fair payment for the work involved.
3. In the result it should yield amounts which are neither too minute nor too large.
4. The price per unit shouldn’t be a veritably small figure or a veritably large one, that is, generally premium particulars will be measured in lower units, cheaper bones in larger units.
5. The unit of dimension may occasionally depend upon the unit for the raw material and/ or labour and/ or important confines. For illustration, gravestone masonry is measured in boxy metres because raw accoutrements are measured in boxy metres. Publishing or pointing is measured in square metres as the labour is considerable.
Que1.5. What are item of workshop? Write the units needed to measure them.
Answer particulars of Works Following are the main particulars of workshop and their measure units
1. Earthwork Earthwork in excavation and channel in stuffing are generally taken out independently under different particulars and amounts are calculated in m3.
2. Concrete in Foundation The concrete is taken out in m3 by length × breadth × consistence. The length and breadth of foundation concrete are generally the same as for excavation only the depth or consistence differs.
3. smirching When the soil is soft or bad, one subcaste of dry slipup or gravestone soling is applied below the foundation concrete. The soling subcaste is reckoned in m2( length × breadth) specifying the consistence.
4. Damp Proof Course( DPC) It’s generally of 2.5 cm thick rich cement concrete 11.5 3 or 2 cm thick rich cement mortar 1 2, mixed with standard water proofing material is handed at the plinth position to full range of plinth wall and the amounts are reckoned in m2( length × breadth). 5. Masonry It’s reckoned in m3( L × B × H). Foundation and plinth masonry is taken under one item, and masonry in superstructure is taken under a separate item.
Que1.6. What are the colorful system of estimation? Explain in detail.
OR
What are the different styles of estimation? Which system you borrow for octagonal bay front structure?
Answer styles of Estimation for Building Works The estimation of structure amounts like earth work, foundation concrete, brickwork in plinth and superstructureetc. can be worked out by long wall-short wall system and center line system.
1. Long Wall- Short Wall Method
i. In this system, the wall along the length of room is considered to be long wall while the wall vertical to long wall is said to be short wall.
ii. To get the length of longwall or shortwall, calculate first the centre line lengths of individual walls. also the length of long wall( out to out) may be calculated after adding half breadth at each end to its centre line length.
iii. therefore the length of short wall measured in to by and may be set up by abating half breadth from its centre line length at each end.
iv. The length of long wall generally decreases from earth work to slipup work in super structure while the short wall increases. These lengths are multiplied by breadth and depth to get amounts.
2. Centre Line Method
i. This system is suitable for walls of analogous cross sections. Then the total centre line length is multiplied by breadth and depth of separate item to get the total volume at a time.
ii. When cross walls or partitions or gallery walls join with main wall, the centre line length gets reduced by half of breadth for each junction.
iii. similar junction or joints are studied precisely while calculating total centre line length. The estimates prepared by this system are most accurate and quick.
iv. Center line system is suitably used for estimating indirect, blockish, hexagonal, octagonaletc., shaped structure . incompletely Centre Line and incompletely Cross Wall Method
- This system is espoused when external( i.e., around the structure) wall is of one consistence and the internal walls having different density. In similar cases, centre line system is applied to external walls and long wallshort wall system is used to internal walls.
- ii. This system suits for different density walls and different position of foundations. Because of this reason, all Engineering departments are rehearsing this system.