Estimating & Costing
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Transcript of Estimating & Costing
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Structure
1.0 Introduction
1.1 Definition
1.2 Need for estimation and costing
Learning Objecyives
After studing this unit, student will be able to
Have an idea of the introduction to estimating and costing.
1.0 Introduction
In the civil engineering field, the construction activity contains the
following three steps.
1. Plans : Preparation of drawings plan, section, elevation, with full
dimension and detailed, specifications meeting the requirements of the proposed
structure.2. Estimation : Preparation of an estimate is for arriving the cost of
the structure to verify the available funds or to procure the required funds for
completion of the proposed structure.
3. Execution (construction) : It is a grounding the proposed structure,
for construction as per the provision contained in drawings and estimation..
Introduction
1UNIT
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The plans contains size of room and dimensions of the work and the estimate
contains the quantity and quality aspects of the structure.
1.1 Definition
Estimation and costing there are two basic points involved in
construction of structures are :
1. Quantity : The quantity aspects is with reference to the measurement
in the drawings (plan, elevation, section)
2. Quality :The quality aspects is with reference to the specifications,
i.e properties of materials, workmanship etc.
Note : The estimation and costing of any structure is defined as the
process of determination of quantities of items of work, and its cost forcompletion.
2. Estimate of a project is therefore, a forecast of its probable cost.
1.2 Need for Estimation and Costing
The object of preparing the estimate for any civil engineering structure is
1. To know the quantities of various items of work, a material and
labour and their source of identification.
2. To decide whether the proposal can match the available funds to
complete the structure.
3. To obtain the administrative and technical sanction of estimate
from the competent authorities to release the funds for construction.
4. To invite tenders or quotations based on the estimate quantities for
entrust of works to the execution.
Short Answer Type Questions
1. What is meant by Estimating and Costing ?
2. State need for Estimation and Costing.
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Structure
2.0 Introduction
2.1 Units of measurements
2.2 Rules For Measurement
2.3 Different methods of tasking out quantities
Learning Objectives
After the studying this unit student will be able to
To measure various quantities as per rules.
2.0 Introduction
The units of differents works depends on their nature, size and shape..In general, the units of different items of works are based on the followingprinciple.
1. Massive or volumetric items of work such as earth work, conceretefor foundations, R.R Masonry , Brick Masonry etc. The measurements oflength, breadth , height or depth shall be taken to compute the volume or cubicalcontents.
2. Shallow, thin and surface work shall be taken in square unit or inarea. The measurements of length and breadth or height shall be taken tocompute the area, Ex. Plastering, white washing etc.
Measurement of Materialsand Works
2UNIT
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3. Long and Thin work shall be taken in linear or running units and
linear measurement shall, be taken. Ex : Fencing, Rainwater pipes,
ornamental borders etc.
4. Single units of work are expressed in numbers. Ex. Doors, Windows,
Rafters, Trusses etc.
2.1 Units of measurement for various items of CivilEngineering Works
Sl.No
1.
2.
3.
4.
5.
Unit of
payment
10.00cum
1.00cum
1.00rmt
10.00cum
10.00cum
1.00cum
1.00cum
1.00cum
1.00cum
Particulars of items
(a) Earth work excavation in all
types of soils except rock re-
quiring blastering.
(b) Earth work excavation in
the soils hard rock requirng
blastering.
(c) Excavation of pipe line
through of specified width and
depth inall types of soils
(d) Earthwork for road for-
mation ,bund formation etc.
cutting , embankment.(e) Refilling of foundations ,
basements, pipe lines, trenches
with excavated soils.
Plain cement concrete for
foundation.
R.R.masonry or brick ma-
sonry for foundation base-
ment, super strucrture, parapet
wall etc.
Filling the basement with
sand.
(a) RCC 1:2: 4 with normal
reinforcement for plinth beam ,
columns, lintels, verandah
beam- T beam etc.
Units of measure-
ments
10.00cum
1.00cum
1.00 rmt
10.00cum
10.00cum
1.00cum
1.00cum
1.00cum
1.00cum
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10.00sqm
10.00sqm
10.00sq m.
1.00Rmt
1.00No
1.00No
1.00Rmt
1.00Rmt
kg/unit
1.00cum
1.00cum
1.00sqm
1.00cum
6.
7.
8.
9.
10
11.
12.
13.
14.
15.
(b) R.C.C 1: 2: 4 for slabs of
specified thickness .Plastering pointing, flooring,
weather proof coarse, white
washing, colour washing, paint-
ing.
Roofing with A.C sheets, tiled
roofing, Kurnool trerrace, Ma-
dras terrace etc.
D.P.C specified width and thick-
ness
Wooden and steel trusses
Doors, windows, ventilators.
Ornamentel border of speci-
fied width and thickness.
R.C.C pipes, A.C pipes GI or
C.I pipes, stone ware pipes
etc.
Steel reinforcement in R.C.C.
Rough stone pitching revet-
ment and soiling of specified
thickness.
(a) Roads works : Metal col-
lections , gravel collections,
solving stones, pitching any
stones, revetment stones etc.
(b) Road works : Spreadingmetal gravel and consolidation
with roller of specified thick-
ness.
(c) Cement concrete pay-
ments of specified thickness.
10.00sqm
1.0.00sqm1.00sqm
10.00sq m.
1.00Rmt
1.00No
1.00 No
1.00Rmt
1.00Rmt
Kg/unit
1.00cum
1.00cum
10.00sqm
10.00cum
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2.2 Rules For Measurement
Measurement of works occupies a very important place in the planningand execution of any work or project, from the time of the first estimate are
made until the completion and settlement of payments. The methods followed
for the measurement are not uiform and the practices or prevalent differ
considerably in between the states. Even in the same state different departments
follow different methods. For convernience a uniform method should be followed
throughout the country. The uniform methods of measurement to be followed
which is applicable to the preparation of the estimates and bill of quantities
and to the side measurement of completed works have been described below.
General Rules
1. Measuremet shall be item wise for the finished items of work and the description of each items shall be held to inculde materials, transport,
labour, fabrication, hoisting, tools and plants, over hands and other
incidental charges for finishing the work to the required shape, size,
design and specifications.
2. In booking dimensions the order shall be in the sequence of length,
breadth and height or depth or thickness.
3. All works shallbe measured not subject to following tolerances unless
otherwise stated.
(a) Dimensions shall be measured to the nearest 0.01 meter i.e 1cm(1/ 211).
(b) Areas shall eb measured to the nearest 0.01 sq.m (0.1 sqft).
(c) Cubic contents shall be worked up to the nearest 0.01 cum(0.1cuft)
4. Same type of work under different condition and nature shall be
measured separately under separate items.
5. The bill of quantities shall fully describe the materials proportions
and work-manships and accurately represent the work to be executed.
Work which by its nature cannot be accurately taken off or which
requires site measuremets shall be described as provisional.
6. In case of structureal concrete, brick work or stone masonry, the
work under the following categories shall be measured separately
and the heights shall be described.
(a) From first floor level
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(b) From plinth level to first floor level.
(c) From first level to second floor level and so on.
The parapet shall be measured with the corresponding items of the
story next below.
Principle of units :The units of different works depend on their nature,
size and shape. In general the units of different item of work are based on the
following principle.
(i) Mass, voluminious and thick works shall be taken in cabic unit or
volumne. The measurement of length, breadth, and height or depth shall be
taken to compute the volume cubic contents(cum).
(ii) Shallow, thin and surface work shall be taken in separate units orin area. The measurement of length and breadth or height shall be taken to
compute the area (sq.m).
(iii) Long and thin work shall be taken in linear or running unit and
linear measurement shall be taken(running meter).
(iv) Piece work, job work etc taken in number
2.3 Different methods of taking out quantities
The items of work like earth work in excavation in foundation, foundation
concrete stone masonry in foundation and basement, stone or brick masonry in
super stucrture may by estimated bu either of the following methods.1. Long wall and short wall method (or) General method
2. Centre line method
2.3.1 Long wall and short wall method
In this method measure or find out the external lengths of walls running
in the direction generally the long walls out-to-out and the internal length of
walls running in the transverse direction in-to-in i.e. of cross or short wall in-
to-in and calculate quantities multiplying the length by the breadth and height of
wall. The same rule applicable to the excavation in foundation, to concrete in
foundaiuon and to masonry.
The simple mehtod is to take the long walls of short or erros walls
separately and to find out the centre to centre lengths of long wall anf short
walls from the plan. For symmetrical footing on either sides, the centre line
remians same for suepr structure and for foundation and plinth.
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For long walls add to the center length one breadth of wall, which
gives the length of the wall out-to-out ,multiplying this length by the breadth and
height and get the quantities,. Thus for finding the quantities of earth work inexcavation, for the length of trench out-to-out add to the centre length one
breadth of foundaiton. Adopt the same process for foudation conceret and for
eacth footing. It should be noted that each footing is to be taken separately and
the breadth of the particular footing is to be added to the centre length.
Long wall length out-to-out = centre to centre length + half breadth on
one side + half breadth on the other side = centre to centre length + one breadth.
For short or cross walls sub tract ( instead of adding) from the centre
length one breadth of wall, which gives the length in-to-in, and repeat the same
process as for the long walls, subtracting one breadth instead of adding.
Short wall length in-to-in= Centre to centre length - one breadth.
That is, in case of long wall add one breadth and in case of short wall
substract one breadth from the centre length to get the corresponding lengths.
It will be noticed that by taking dimensions in this ways, the long walls
are gradually decreasing in length from foundation to superstructure, while the
short walls are increasing in length.
This method is simple and accurate and there is no chance of any mistake.
This method may be named as long wall and short wall method, or general
method.
2.3.2 Centre line method
In this method known as centre line method. This method is easy and
quick in calculations. In this method sum total length of centre lines of all walls,
long and short has to be found out. This method is well suitable for walls of
similar cross sections. In this method the total centre line multiplied by breadth
and depth of concerned item gives the total quantity of each item. In this method,
the length will remain same for excavation in foundation for concrete in foundation,
for all footings and for super structure (with slight difference where there are
cross walls or number of junctions). It requires special attention and consideration
at the junctions, meeting points of partition or cross walls, etc.
For rectangular, circular polygonal (hexagonal, octagonal etc) building
having no inter or cross walls, this method is quite simple. For each junction half
breadth of the respective items or footings is to be deducted from the total
centre length. Thus in the case of a building with one partition wall or cross wall
having two junctions, for earthwork in foundation trench and foundation concrete
deduct one breadth of trench or concrete from the total centre length (half breadth
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for one junction and the breadth ( 2 x 1/2 = one) for two junctions. For footings,
similarly deduct one breadth of footing for two junctions from the total centre
length and so on. If two walls come from opposite directions and meet a wall atthe same point, than there will be two junctions.
In the case of a building having different type of walls, suppose the other
(main) walls are of A type and inter cross walls are of B type, then all A type
walls shall be taken jointly first , and then all B type walls should be taken
together separately. In such cases no deductions of any kind need be made for
A type walls, but when B type walls are taken, for each junction deducting of
half breadth of A type wall (main wall) shall have to be made from the total
centre length of walls.
It may be noted that at corners of the building where two walls are
meeting no substraction or addition is required.
Note : Student should practice method I first and when they have become
sufficiently acquainted with method I, then only they should take up the method
II.
Short Answer Type Questions
1. Write the unit of measurements. Earthwork, P.C.C, R.C.C, Masonary,
Plastering, Flooring, Fencing, Ornamental border, Door, Windows,
Trusses etc.
2. Write general rules for measurement.
3. Write different methods of taking out quantities and describe.
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Structure
3.0 Introduction
3.1 Detailed estimate
3.2 Preliminary or approximate estimate
3.3 Problems in preliminary estimate
Learning Objectives
After studying this unit student will be able to
Understand the definition of detailed estimate, stages of preparation
of estimate, Data required for an estimate and types of estimate.
3.0 Introduction
An estimate is a probable cost of a work. It is usually prepared before
the construction is taken up. The primary object of an estimate is to know
beforehand the cost of the work. The actual cost of the work is known after thecompletion of the work. If the estimate is prepared carefully and correctly there
will not be much difference in the estimated cost and actual cost. The estimator
should be fully acquainted with the methods of construction, skilled and
experienced for accurate estimating.
3UNIT
Types of Estimates
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3.1 Detailed estimate
The estimate may be approximate or preliminary estimate or accurateestimate. In approximate estimate the approximate cost of the work is estimated.
In the accurate estimate the details of various items are taken and calculated.
3.1.1 Definition
The estimate prepared by dividing the work into different items, taking
detailed measurements of each item of work and calculating their quantities is
known as detailed estimate.
3.1.2. Stages of preparation
To prepare the complete estimation of the project, besides the estimated
cost of different main items of work, The cost of preliminary works and surveying,cost of land and its acquisition, cost of leveling and preparation of ground and
the cost of external services are to be provided. Provision of supervision charges
and contractors profit are to be provided in the estimate.
Data required for preparing an estimate : To prepare an estimate
for a work the following data are necessary.
Drawings : The detailed drawings of plan, elevation and section, drawn
to a scale are necessary to take the details of measurements of various items of
work.
Specifications : The specifications gives the nature, quality and classof materials, their proportion, method of execution and workmanship and the
class of labour required. The cost of the work varies with its specifications. The
cement mortar with 1:3 is more costlier than cement mortar with 1:6.
Rates :The rates for various items of work, the rates of various materials
to be used in construction, the wages of different categories of labour should be
available for preparing an estimate. The location of the work and its distance of
source of materials and cost of transport should be known. These rates may be
obtained from the Standard Schedule of Rates prepared by the engineering
departments.
3.1.3 Details of measurements and calculation of quantities and abstract of estimated cost
To prepare an accurate estimate, a detailed estimate of quantities of
various items of work and an abstract estimate of the quantities and their unit
rates are required.
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Detailed Estimate
Abstract estimate
3.2. Preliminary or approximate estimate
Preliminary or approximate estimate is required for preliminary studies
of various items of work or project , to decide the financial position and policy
for administrative sanction by the competent authority. The preliminary estimate
is prepared by different methods for different types of works. The various
methods of preparing the preliminary estimate are plinth area estimate, cubical
rate estimate and estimate per unit base.
3.2.1 Plinth area estimate
The plinth area rate is calculated by finding the plinth area of the building
and multiplying by the plinth area rate. The plinth area rate is obtained by
comparing the cost of the cost of similar building having similar specifications in
the locality.
3.2.2. Cubic area estimate
The cubic rate estimate is prepared on the basis of the cubical contents
of the building. The cubic rate is obtained from the cost of the similar building in
the locality having similar specifications. The cost of the building is estimated by
multiplying the volume of the building with the cubic area rate. Cubic rate estimate
is more accurate as compared to the plinth area estimate.
3.2.3 Estimate per unit base
The preliminary estimate may be prepared for different structures and
works by various ways. For schools and hostels, per class rooms for schools,per bed for hospitals, per seat for theater halls, etc. For roads and highways and
for irrigation works, the preliminary estimate is made per kilometer. For bridges
and culverts per running meter. For sewerage and water supply projects on the
basis of per head of population served.
S.no Description of work No Length Breadth Height/Depth Quantity Remarks
S.No. Description of work Quantity Rate Per Amount
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3.3. Problems in preliminary estimate
1. If the cost of school building per student is Rs. 25000. Calculate thecost of school building for 100 students.
Cost of the school building for 100 students = Rs.
25000x100=Rs.2500000.
2. If the cost of construction of 1 km. length of a highway is Rs.
10000000. Find the cost of construction for 20 km.
Cost of construction for 20 km = Rs. 10000000x20=Rs.200000000.
3. If the plinth area rate of a residential building is Rs.10000/sq m.
Calculate the cost of construction of a residential building of 100 sq. m.
Cost of construction of 100 sq. m.= plinth area rate x area =
10000x100=Rs.1000000
Summary
Detailed estimate consists of taking the detailed measurements of length,
breadth, height and calculating the quantities.
Data required for estimate :Drawings, specifications and rates.
Types of preliminary estimates : Plinth area estimate, cubic rate
estimate and estimate per unit base.
Short Answer Type Questions
1. Define detailed estimate.
2. What are stages for preparation of an estimate?
3. List out the data required for preparation of an estimate.
4. Write the tabular form for the detailed estimate.
5. Write the tabular form for preparation of an abstract estimate.
Long Answer Type Questions
1. Describe the various types of preliminary estimates.
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Structure
4.0 Introduction
4.1 Single roomed building (load bearing structure)
4.2 Two roomed building( load bearing type structure)
4.3 Single storied residential building with number of rooms (load bearing
type structure)
4.4 Single storied residential building with number of rooms (framed
structure type)
4.5 Primary school building with sloped roof
4.6 RCC Dog legged open well stairs
4.7 Two storied residential building (framed structure type)
4.8 Detailed estimate of compound wall and steps
Learning Objectives
After studying this unit student will be able to
Prepare detailed estimates of single roomed, Building roomed, Doubleroomed buildings, for load bearing walls and Framed structures. Detailed Esti-mate of Primary School Building, Compound walls and steps. Detailed estimateDog legged and Open Well STair case. Preparational estimate for ground andfirst floor.
4UNITDetailed and AbstractEstimate of Buildings
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4.0 Introduction
To estimate the cost of any building or a structure, drawings,specifications and rates are required. Regarding the detailed estimate by long
wall and short wall method and centre line method, the drawings consisting of
plan elevation and section are sufficient. The estimator should be able to take all
the dimensions from the drawings. The length and breadth are taken from the
plan, while the height or depth are taken from the section and elevations. In long
wall and short wall method the walls are taken separately, while in the centre line
method, the centre line lengths of all the walls are combined. The accuracy of
estimate depends upon the skill of the estimator in studying the drawings. The
long wall and short wall method is useful for load bearing type structure, but it
cannot be applied for framed structure.
4.1 Single roomed building (load bearing structure)
There are two steps in estimating the cost of a building or a structure.
1. Taking out quantities and calculation of quantities in detailed estimate.
2. Determining the cost from the abstract estimate.
Long wall and short wall method : This method is also called as
separate or individual wall method. This is simple and it gives accurate values.
The following procedure is adopted.
1. The dimensions of long wall and short wall should be taken separately.2. Irrespective of its lengths, the wall which is taken first is long wall and
the wall which is taken next is the short wall.
3. The centre line of the wall of the building is considered for determining
the centre to centre line length of long walls and short walls.
4. The centre to centre to centre length of long walls or short walls is
obtained by adding half the width of the wall to the internal length of
either long wall or short wall.
5. Centre to centre length of long wall = internal length of long wall +
width of the wall.
6. Centre to centre length of short wall = internal length of short wall +
width of the wall.
7. To determine the lengths of different quantities such as earthwork,
c.c. bed in foundation, R.R. masonry etc, length of long wall = centre
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to centre length of long wall + width, the width is the respective
width of the item in consideration.
8. Similarly length of the short wall = centre to centre length of the short
wall width, where the width is the respective width of the item
such as earthwork, c.c. bed etc.
Centre line method : In the centre line method, the sum of all the
centre line lengths of long walls and short walls are added to get the total centre
line length. At the junctions of two walls, the length is present in both of the
walls. Hence half of the length of that width is to be subtracted from the total
centre line length.
Length = Total centre line length width x number of junctions.
Fig 4.1 Plan Single Room
Centre to centre length of long wall = 6.0 + 2x0.3/2 = 6.3 m.
Centre to centre length of short wall = 4.0 + 2x0.3/2 = 4.3 m.
Length of Long Wall = Centre to centre Length of Long Wall + Width
Length of Short Wall = Centre to centre Length of Short Wall width
For earth work in excavation Length of Long Wall = 6.3 + 1.2 = 7.5 m.
E L E V A T I O N S E C T I O N
1. 20. 90. 70. 5
0.30.60.3
3.0
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For earth work in excavation Length of Short Wall = 4.3 1.2 = 3.1 m.
In cement concrete in foundation the length and width of the long walland short wall are the same, but the height is different from that of the foundation
For R.R. masonry First footing Length of long wall = 6.3 + 0.9 = 7.2 m.
Length of Short Wall = 4.3 -0.9 = 3.4 m.
Similarly for second footing & Third footing, Length of Long Walls are
7.0 and 6.8 and for short walls are 3.6 m and 3.8 m respectively.
Detailed estimate of a single roomed building by centre line method
Centre to centre length of long wall = 6.0 + 2x0.3/2 = 6.3 m.
Centre to centre length of short wall = 4.0 + 2x0.3/2 = 4.3 m.
Total centre line length = 2(6.3 + 4.3) = 21.2 m.
Detailed Estimate
Quantity
30.528
7.63
11.45
4.45
12.72
28.62
19.08
RemarksSl. No.
1
2
3
4
Description
of work
Earth work in
excavation
C.C. bed infoundation
R.R. masonry
in foundation
and plinth
First footing
Second footing
Basement
Brick work in
super structure
No.
1
1
1
1
1
1
L
21.2
21.2
21.2
21.2
21.2
21.2
B
1.2
1.2
0.9
0.7
0.5
0.3
H
1.2
0.3
0.6
0.3
1.2
3
m m m m3
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Sl.
No.
1
2
3
Description of work
Earth work in
excavation in
foundation
Long Walls
Short Walls
Plain cement concrete
in foundation (1:5:10)
Long Walls
Short Walls
R.R. Masonry in
foundation
& basement c.m (1:8)
First footing
Long Walls
Short WaLLS
Second footing
Long Walls
Short WaLLS
Basement
Long Walls
Short Walls
No.
2
2
2
2
2
2
2
2
2
2
L
m
7.5
3.1
7.5
3.1
7.2
3.4
7
3.6
6.8
3.8
B
m
1.2
1.2
1.2
1.2
0.9
0.9
0.7
0.7
0.5
0.5
H
m
1.2
1.2
Total
0.3
0.3
Total
0.6
0.6
0.3
0.3
1.2
1.2
Quantity
m3
21.6
8.93
30.53
5.4
2.68
8.08
7.78
3.67
11.45
2.94
1.51
4.45
8.16
4.56
Remarks
L=6.3+1.2=7.5
L = 4 . 3 -
1.2=3.1
L=6.3+1.2=7.5
L = 4 . 3 -
1.2=3.1
L=6.3+0.9=7.2
L = 4 . 3 -
0.9=3.4
L=6.3+0.7=7.0
L = 4 . 3 -
0.7=3.6
L=6.3+0.5=6.8
L = 4 . 3 -
0.5=3.8
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4.2 Two roomed building( load bearing type structure)
Detailed Estimate Of A Double Roomed Building By Long Wall AndShort Wall Method
Centre to centre length of long wall = 5.0 + 0.3 + 5.0 + 2x0.3/2 = 10.6m.
Centre to centre length of short wall = 5.0 + 2x0.3/2 = 5.3 m.
Number of long walls = 2. Number of short walls = 3.
Length of long wall = centre to centre length of long walls + width
Length of short wall = centre to centre length of short wall - width
4 Brick work in super
structure c.m. ( 1:8)
Long Walls
Short Walls
2
2
Totalof
6.6
4
R.R.
0.3
0.3
masonry
3
3
12.72
28.62
11.88
7.2
19.08
L=6.3+0.3=6.6
L = 4 . 3 -
0.3=4.0
Sl. No.
1
2
Description of
work
Earthwork in
excavation
Long Walls
Short Walls
C.C. bed in
foundation
Long Walls
No.
2
3
2
L
m
11.8
4.1
11.8
B
m
1.2
1.2
1.2
H
m
1.2
1.2
Total
0.3
Quantity
m3
33.98
17.71
51.69
8.5
Remarks
L= 10.6 +
1.2 = 11.8
L = 5.3 -
1.2 = 4.1
Total centre to centre line lenght = 10.6 x 2 + 5.3x3 = 37.1 m
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3
4
Short Walls
R.R. masonry in
foundation &
plinth
First footing
Long Walls
Short walls
Second footing
Long Walls
Short Walls
Third footing &plinth
Long Walls
Short walls
Brick work in
super structure
Long Walls
Short Walls
3
2
3
2
3
2
3
2
3
4.1
11.5
4.4
11.3
4.6
11.1
4.8
10.9
5
1.2
0.9
0.9
0.7
0.7
0.5
0.5
0.3
0.3
0.3
0.6
0.6
0.3
0.3
1.2
1.2
3
3
4.43
12.93
312.42
7.13
19.55
4.75
2.9
7.65
13.32
8.64
21.96
49.16
19.62
13.5
33.12
L = 10.6 +
0.9 = 11.5
L = 5.3 - 0.9
= 4.4
L = 10.6 +
0.7 = 11.3
L = 5.3 -0.7
= 4.6
L = 10.6 +
0.5 = 11.1
L = 5.3 - 0.5
= 4.8
L = 10.6 + 0.3 =
10.9
L = 5.3 - 0.3 =
5.0
R.R. masonry Total
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Centre line method
Fig 4.2 Double Room
No.
1
1
1
1
1
1
1
L
35.9
35.9
36.2
36.4
36.6
36.8
B
1.2
1.2
0.9
0.7
0.5
0.3
H
1.2
0.3
0.6
0.3
1.2
Total
3
Sl. No.
1
2
3
4
Description of
work
Earthwork in
excavation
C.C. bed in
foundation
R.R. masonry in
foundation
First footing
Second footing
Basement
Brickwork in
superstructure
Remarks
L= 37.1 -
2x1/2x1.2
L = 37.1 -
2x1/2x0.9
L = 37.1 -
2x1/2x0.7
L = 37.1 -
2x1/2x0.5
L = 37.1 -
2x1/2x0.3
Quantity
51.69 m3
12.93 m3
19.55 me
7.65 m3
21.96 m3
49.165 m3
33.12 m3
E L E V A T I O N S E C T I O N
5m x 5 m5 m x 5 m
1. 20. 90. 70. 5
0.30.60.3
3.0
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Construction Technology172
4.3 Single storied residential building with number of rooms (load bearingtype structure)
Length of long walls = 6.0+0.3+5.0+2x0.3/2=11.6 m.
Number of long walls = 3
Length of short wall of 5.0 m. length = 5.0+2x0.3/2=5.3 m.
Number of 5.0 m shortwalls =3
Length of 4.0 m. length short walls = 4.0+2x0.3/2=4.3m.
Number of 4.0 m. length short walls = 3
Total centre line length = 11.6x3+5.3x3+4.3x3=63.6m.
Fig 4.3 Plan Section
6.0 x 5.0 m 5.0 x 5.0 m
5.0 x 4.0 m5.0 x 4.0 m
D D
DD
D D
0.30.6
0.3
0.9
0.9
1.2m
3.0m
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56.43
m mm m3
5m4m
5m4m
5m4m
5m4m
Basement
Basement
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4.4 Single storied residential building with number of rooms (framed structure type)
Number of columns in a framed structure = 9
Size of the columns = 230 mmx230 mm
Length of R.R. masonry, Brickwork, lintels, plinth beam and beams
under slab = (6+6)x3+(5+4)x3=63 m.
Length of sunshades and external plastering = (12.9+9.9)x2= 45.6 m.
Length of slab with 1 m. extension on both sides = 1.0+1.0=2.0 m.
External Plastering : Area of external plastering = Length x Height
Length of Plastering = 2x(12.9+9.9)=45.6 m.
Height of external plastering = 3.0+0.12, where 3.0m is the height of
the room and 0.12 m. is the thickness of the slab.
Internal plastering : Area of internal plastering = Length x Height
Length of plastering = 2(L+B) , Where L and B are the length and
breadth of the room respectively.
For 6mx5m room, length = 2(6+5)=22m. Similarly for 5mx4m room,
length =2(5+4)=18 m.
Fig 4.4 Residential Building Framed Structure
6.0 x 5.0 m 5.0 x 5.0 m
5.0 x 4.0 m6.0 x 4.0 m
P L A N S E C T I O N
0.23 x 0.23
R.C.C Column3.0 m
1.2 m
0.9 m
0.3 m
0.3 m
R.C.C.
Footing
R.C.C.
G.L G.L
100 mm
thick
RCC slab
1.2 m
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B
m
1.2
0.9
0.6
1.2
0.9
0.6
0.7
0.45
0.23
0.23
0.23
1.2
0.23
S.
No.
1
2
3
4
5
Description of work
Earthwork in excavation
Columns
In between columns
Deduct for columns
C.C. bed in foundation
Columns
In between columns
Deduct for columns
R.R. masonry in
foundation
First footing
Second footing
Brickwork in
superstructure
Deductions Doors
Windows
R.C.C. column footing
Trapezoidal section
Stem
No.
9
1
9
9
1
9
1
1
1
6
8
9
9
9
L
m
1.2
63
0.6
1.2
63
0.6
63
63
63
1
1.2
1.2
0.23
H
m
1.8
0.9
0.9
0.3
0.3
0.3
0.6
1.2
3
2
1.2
0.3
0.3
5.1
Quantity
m3
23.33
51.03
-2.92
71.44
3.89
17.01
-0.972
19.93
26.46
34.02
60.48
43.47
-2.76
-2.65
38.06
3.89
2.44
2.43
8.76
Remarks
L=12x3+
9x3=63
H=0.9+1.2+
3.0=5.1
Net Brickwork in super structure
(1.44+4x0.985+0.053)/6
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Construction Technology176
6
7
8
9
10
11
R.C.C. Plinth beam
R.C.C. inlintels&sunshades
Lintels
Sunshades
R.C.C. slab and beams
Beams under slab
1m. Projection from
slab
R.C.C. Slab.
External plastering
20 mm
Thick
Deductions
Doors
Windows
Internal Plastering
12 mm thick
Rooms 6mx5m
Rooms5mx4m
Sand filling in rooms
Rooms 6mx5m
1
1
1
19
1
1
6
8
2
2
2
63
63
45.6
63
1
14.9
45.6
1
1.2
22
18
6
0.23
0.23
0.7
0.23
0.23
11.9
5
0.3
0.1
0.07
0.3
0.3
0.12
3.12
2
1.2
3
3
1.2
4.35
1.45
2.23
3.68
4.35
0.62
21.28
26.25
142.27
-12
-11.52
118.75
132
108
240
72
L=2(12.9+
9.9)=45.6
L=12.9+1.0+
1.0=14.9
B=9.9+1.0+
1.0=11.9
L=2(12.9+9.9)
=45.6
H=3.0+0.12
L=2(6+5)=22
L=2(5+4)=18
Net External plastering area
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4.5 Primary school building with sloped roof
Wall thickness = 0.3 m. in brick masonry.
Width of foundation = 1.2 m. Depth of foundation = 1.8 m.
Width of first footing = 0.9 m. Depth of first footing = 0.9 m.
Second footing width = 0.7 m. Depth = 0.6 m.
Width of third footing and plinth = 0.5 m. Height = 0.9 m.
Centre to centre length of long walls = 3.0+0.3+3.0+2x0.3/2=6.6 m.
Centre to centre length of short walls = 3.0+2x0.3/2=3.3 m.
Total centre line length = 6.6x2+3.3x3=23.1 m.
Number of junctions = 2.
Height of the sloping roof =1.0 m.
12
13
14
Rooms 5mx4m
C.C. bed in rooms
Rooms 6mx5m
Rooms5mx4m
Flooring in rooms
Rooms 6mx5m
Rooms5mx4m
Fabrication &
placement of
steel
2
2
2
2
2
5
6
5
6
5
4
5
4
5
4
1.2
0.1
0.1
48
120
6
4
10
60
40100
(8.76+4.35+3.68+26.25)x1.25x87.5/100x1000 78.5x100/100x1000
tonnes 4.22 t
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Length of the sloping roof = square root of (1.5mx1.5m + 1.0m.x1.0
m.) = 1.8 m.
Number of gable rafters at a spacing of 30 cms. Centre to centre =(
6.0/0.3)+1=21
Length of the gable rafters = 1.8+1.8+0.5+0.5=4.6 m.
Number of reapers along a length of 6.05 mts. At a spacing of 10 cms
each = (4.6/0.1)+1=47
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ELEVATION
W W
DD
Room
3.0 x 3.0 m
Room
3.0 x 3.0 m
References
D - Door 1.00 m x 2.00 m
W - Window 1.2 m x 1.2 m
Width of 1st footing : 0.9 m
Second footing : 0.7 m
Basement : 0.5 m
P L A N
S E C T I O N
Tiles
Tiles
1.2 m
0.9 m
0.6 m
0.3 m
0.9 m
0.9 m
0.6 m
0.3 m
0.9 m
2.0 m
1.5 m
0.9 m
PRIMARY SCHOOL BUILDING WITH SLOPING ROOF
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4.6 RCC Dog legged open well stairs
Fig 4.5 Dog Legged Stair case
1650
250
150
Floor
1650
2500 1000
E L E V A T I O N S E C T I O N - A A
P L A N
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Sloping side 2 2 0.28 2.4640. 411.264Total
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Length of the inclined flight = Square root of (1.65x1.65+2.5x2.5)=3.0m.
Size of base of flight = 1.0x0.5x0.25 m3
Landing at the middle and top floor =2.0mx1.0mx0.15m.
Length of the hand rail = (2x3.0+0.40)=6.8 m.
Number of risers = 11
Height of the first flight = 11x0.15=1.65 m.
Number of treads = 10
Length of treads in each flight = 10x0.25=2.5 m.
Triangular portion of the brick has a base of 0.25 m. and height 0.15 m.
Area of the brickwork = 1/2x(0.25x0.15) m2.
4.6.1 Open Well Staircase
Fig 4.6 Open well Stair case
Flig
htNo.
No.
ofRisers
No.o
fTrea
ds
Eac
hRiser
Eac
hTrea
d
A
8
8
152
300
B
4
3
152
300
C
8
7
152
300
SECTION AT AA
Note :
1. All dimensions are in Milli meters
2. Follow the written dimensions only
OPEN WELL TYPE STAIRCASE
Scale 1:50
DRG. No. 18
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Flight No. A
Horizontal distance of treads = 0.3x8=2.4 m.
Height of risers = 0.15x9=1.35 m.
Sloping length of flight = Square root of(2.4x2.4+1.35x1.35)=2.75 m.
Flight No. B
Horizontal length of treads = 0.3x3=0.9 m.
Height of risers = 0.15x4=0.6 m.
Sloping length of flight= Square root of (0.9x0.9+0.6x0.6)=1.08 m.
Flight No. C
Horizontal length of treads = 0.3x7=2.1 m.
Height of risers = 0.15x8=1.2 m.
Sloping length of flight = Square root of (2.1x2.1+1.2x1.2)=2.42 m.
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Construction Technology184
4.7 Two storied residential building (framed structure type)
Fig 4.7 Two storied residential building
E L E V A T I O N
Parpet wall
Weathering
course
Lintel &
sunshade
Brick
masonry
Roof slab
C.C. flooring
R.C.C Mix
1:4:1Sand filling
C.C. floring
1:4:8Elevation
0.902
3.05 m
3.05 m
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Fig 4.8 Ground Floor & First Floor
Ground floor
Number of columns = 15
Height of columns in ground floor & first floor =
0.90+0.9+3.05+0.1+3.05+0.1+0.8=8.9 m.
Height of column in ground floor = 0.9+9+3.05+0.1=4.95 m.
Height of column in first floor = 3.05+0.1+0.8=3.95 m.
Length of brickwork, lintels and beams =
4.21x4+4.20x4+3.05x2+3.00x2+2.00x2+4.00x2+3.34x2 = 64.42 m.
Openings Main door 1.00mx2.1m -1 No., Door D 0.9x2.1 3Nos., Door D1 0.76x2.1 2 Nos.
Windows - W 1.8mx1.2m 5 Nos., W1 1.2mx1.2m 2 Nos.
Length of wall 100 mm. thick = 4.21+3.79+1.5= 9.5 m.
Length of sunshade = 2.1x5+1.5x2+1.1x1+1.3x1 = 15.9 m.
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Length of slab = 12.68 m., Width of slab = 9.10 m.
Length of external plastering = 2(12.68+9.10)=43.56 m.
Trapezoidal section of the column foundation : Area of base A1 =
1.0x1.0=1.0 m2.
Area of the column stem = 0.23x0.23=0.0529 m2=A2
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Construction Technology190
4.8 Detailed estimate of compound wall and steps
Length of the compound wall between the brick columns 230 mm x
230 mm = 6.0 + 4.0 = 10.0 m.
Height of the compound wall = 1.5 m.
Depth of excavation below ground level = 0.9 m.
Width of the foundation = 0.9 m.
Thickness of the C.C. bed = 0.3 m.
Size of the first footing = 0.6 m. x 0.6 m.
Size of the plinth = 0.45 x 1.0m2.
Size of the brickwork in columns = 0.23 x 0.23 x 1.5 m.
Number of brick columns = 3
Length of the earthwork in excavation =
6.0+0.23+0.23+4.0+0.23=10.69
Quantity of earthwork in excavation = 10.69x0.9x0.9=8.66 m3.
Quantity of C.C. bed in foundation = 10.69x0.9x0.3=2.89 m3.
R.R. masonry first footing = 10.69x0.6x0.6= 3.85 m3.
R.R. masonry in plinth = 10.69x0.45x1.0= 4.81 m3.
R.R. masonry total = 3.85+4.81= 8.66 m.
Brick masonry in columns = 3x0.23x0.23x1.5=0.24 m3.
Brickwork in between columns = 10.0x0.10x1.5= 1.5 m3.
Total brick masonry = 0.24+1.5=1.74 m.
Deduction for gate 2.0mx1.5m = 2.0x0.1x1.5=0.3 m3.
Net brickwork in superstructure = 1.74-0.3 = 1.44 m.
Plastering in columns = 4x0.23x1.5x3=4.14 m2.
Plastering in between columns = 10x1.5x2=30 m2.
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Total area of plastering = 4.14+30=34.14 m2.
Estimate of steps
Quantity of first step = 1.0x0.9x0.3=0.27 m3.
Quantity of second step = 1.0x0.6x0.3=0.18 m3.
Quantity of third step = 1.0x0.3x0.3=0.09 m3.
Total quantity of brickwork in steps = 0.27+0.18+0.09=0.54 m3.
1.5 m
1.0 m0.45
0.6
0.9 m
0.3 m
0.6 m
0.23m
0.23
4.0 m
0.23
6.0m0.23
0.15
0.15
0.15
0.3
0.3
0.3
1.0 m
Top view
Front View
Side View
Fig. 4.9 Plan and Section of a compound Wall
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Summary
To estimate the cost of a building or a structure the steps involved are
1. Taking out the measurement of various items and calculate the
quantities as per the detailed estimate.
2. Determining the cost of the calculated quantities as per Abstract
estimate.
The methods of calculating quantities are Long wall and short wall method
and Centre line method.
Length of Long wall = Centre to centre length of the long wall + width
Length of short wall = Centre to centre length of the short wall widthIn centre line method, the length = Total centre line length (number of
junctions)xwidth/2
For a double room building, the total centre line length = sum of the
centre line lengths of two long walls and three short walls. The number
of junctions = 2.
For a building with number of rooms, the total centre line length = sum
of the centre to centre lengths of three long walls, three short walls of length 5.3
m. and three short walls of length 4.3 m. Number of junctions = 6.
The long wall short wall method and the centre line method are notapplicable. The lengths of the R.R. masonry, Brickwork in superstructure, Plinth
beam, lintels and beams under slab are obtained by adding the internal dimensions
of the rooms.
The roof for the primary school building is a gable roof, having its slope
in two directions. The roof under consideration is the roof having its width = 3.0
m. and its length = 6.0 m.
Length of the gable rafter = square root of [(width/2)2 + (Rise)2]
Number of gable rafters = Length of the roof/ spacing of the rafters.
Area of the tiled surface = 2x(Length of the roof )x Width of the slopingside.)
Number of risers = Height of the flight/ rise.
Number of treads = Number of risers 1.
Treads length = Number of treads x Tread.
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Horizontal length of the stairs = Treads length + Width of the landing
Length of the sloping side = Square root of [(Treads length)2 + (Height
of flight)2].
Area of brickwork in each step = (Rise x Tread) x .
Short Answer Type Questions
1. What are the steps involved in finding the cost of the building?
2. What are the methods involved in taking measurements in a detailed
estimate.
3. Write the tabular formula of a detailed estimate.
4. Calculate the number of risers in a flight of height 1.50 m. and the rise of 15 cms.
5. If the number of risers = 10, find the number of treads.
6. Find the length of the gable rafter for a room of width 6.0 m. and
length 12.0 m and the rise is 1.5 m.
Long Answer Type Questions
1. Find the earthwork in excavation, C.C. bed in foundation, R.R.
masonry in foundation, Brick work in superstructure and plastering for single
room building and double room building by long wall short wall method and
centre line method.2. Detailed estimate of a dog legged stair case.
3. Detailed estimate of compound wall and steps.
O.J.T. Type Questions
1. Detailed estimate of a number of rooms.
2. Detailed estimate of a framed structure.
3. Detailed estimate of a Primary school building.
4. Detailed estimate of an open well stair case.
5. Detailed estimate of a double storied building.
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Structure
5.0 Introduction
5.1 Prepare specifications for different items of work.
5.2 Find the cost of materials at source and at site.
5.3 Study of the cost of labor types of labor using standard schedule
of rates
5.4 Concept of lead and lift- leads statement
5.5 Preparation of unit rates for finished items of works
Learning Objectives
After studying this unit student will be able to
Prepare the unit ratio of various items of works. Find the cost of
materials, specifications of various of various items of works.
5.0 Introduction
To estimate the cost of the building, the quantities of various items of
work are calculated from the drawings. The unit rates of various items of work
are calculated from the specifications of the various types of materials. The rates
are calculated as per the rates in the standard schedule of rates. The unit rates of
various items of work increase considerably with the specifications. The
5UNIT
Specifications and Analysis
of Rates
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specifications indicate the quality of the work while the drawings are used for
the quality of the work.
5.1 Prepare specifications for different items of work
Specifications specifies or describes the nature and the class of work,
materials to be used in the work, workmanship etc. From the study of the
specifications one can easily understand the nature of the work and what the
work shall be.
Detailed specifications : Detailed specifications are written to express
the requirements clearly in a concise form avoiding repetition and ambiguity.
The detailed specifications for various items of work are as follows.
Earthwork excavation of foundation
The following specifications shall be followed in the earthwork in
excavations in foundations.
1. Foundation trench shall be dug to the exact width and depth of
foundation.
2. Excavated earth shall not be placed within 1 m. of the edge of the
foundation.
3. The bottom of the trenches shall be perfectly leveled both
longitudinally and transversely.
4. If water accumulates in the trench, it should be pumped out. Care should be taken to prevent water from entering the trench.
5. If rocks and boulders are found during excavation, they should be
removed and the bed of the trench should be leveled and
consolidated.
6. Foundation concrete should be laid only after the inspection and
approval by the Engineer in charge.
Cement concrete in foundation (1:5:10)
The following specifications should be followed in cement concrete in
foundation.
1. Course aggregate should be of hard broken stone, free from dust,
dirt and foreign matter.
2. Fine aggregate shall be of coarse sand, consisting of hard, sharp and
angular grains and shall pass through screen of 5 mm. square mesh.
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3. Sand should be free from dust, dirt and organic matters.
4. Water shall be clean and free from alkaline and acid matter.
5. Mixing should be done on masonry platform or sheet iron tray in
hand mixing.
6. Coarse aggregate and sand should be mixed by volume and cement
by weight.
Random rubble masonry
The following specifications should be followed in random rubble
masonry
1. The stones should be sound, hard and durable. Stones with rounded
surface shall not be used.
2. No stone shall be less than 15 cm. in size.
3. Bond stones should be provided at every 1 m. length.
4. Cement mortar 1:3 to 1:6 shall be provided.
5. The joints in the stone masonry shall not be thicker than 2 cm.
6. The masonry shall be watered for at least 10 days.
Brick masonry
The following specifications should be followed in brick masonry firstclass
1. Bricks of standard size, copper red color, regular in shape, having
sharp square edges should be used.
2. The bricks should not absorb more than 20% of water when immersed
in water for 24 hours.
3. The mortar used in brick masonry shall be 1:3 to 1:6.
4. The bricks shall be well bonded and laid in English bond unless
otherwise specified.
5. Mortar joints shall not exceed 6 mm. in thickness and the joints shall
be fully flushed with mortar.
6. The bricks should be soaked in water before use in masonry.
7. The brick masonry shall be watered for at least 10 days.
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Plastering
The following specifications should be followed in plastering
1. The materials of mortar, cement and sand used in plastering should
be as per specifications.
2. The joints of the brickwork shall be raked for a depth of 18 mm. on
the surface.
3. Ceiling plastering should be completed before the start of wall
plastering.
4. The thickness of the plastering should not be less than 12 mm. for
internal plastering and 20 mm. for external plastering.
5. The plastering work shall be checked for horizontality with a straight edge and for verticality with a plumb bob.
6. Any defective plastering shall be cut in rectangular shape and replaced.
7. The plastering should be watered for at least 10 days.
5.2 Find the cost of materials at source and at site.
The amount required to purchase the material at the source of its
production is the cost of materials at the source.
Cost of materials at site : The cost of materials at site includes the
cost of materials at source along with the cost of seignories, taxes, royalties,transport, stacking, loading and unloading etc.
Seignories are collected for materials like sand, stones etc., which are
under the control of respective local agencies under government control.
5.3 Study of the cost of labor types of labor using standard schedule of rates
Labour rates
Si
No.
Category of worker
S. Rate
For
2012-13
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1 2 3
Skilled catregory
1 Bar bender 330
2 Black smith / Tin smith / Rivetor 315
3 Blaster ( Licensed ) 355
4 Carpenter Cl- I 315
5 Electrician ( Licensed ) 355
6 Fitter Cl- I 315
7 Floor Polisher / Tile Layer 315
8 Foreman 355
9 Gauge reader 300
10
Maistry / Work Inspector with Non-technical Qualification
SSLC/SSC/HSC
300
11 Mason Cl- I / Brick layer Cl- I 315
12 Mechanic Cl- I 315
13 Operator Air compressor / DG set 315
14 Operator Batching plant 355
15 Operator Bus/Ambulance/ Lorry/ Tanker 315
16 Operator Concrete / Asphalt mixer 315
17 Operator Concrete / Asphalt paver 315
18 Operator Concrete pump / Placer/ ice plant 315
Common SoR 2012 : 13
280
Sl
No.
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199Paper - II Estimating and Costing
Category of worker
S. Rate
for
2012-13
1 2 3
19 Operator Core drilling machine 355
20 Operator Crane/ Tower crane/ Cable way 355
21 Operator Drilling jumbo / Loco / Winch 315
22 Operator Grouting/ Guniting/ Shotcreting 315
23 Operator Jackhammer/Pneumatic tamper 315
24 Operator Pump / Ventilation fan 315
25 Operator Lathe/Drilling/Shearing machine 355
26 Operator Bending / Planing machine 315
27 Operator Road roller 315
28 Operator Shovel / Scraper / Dozer 355
29 Operator Spillway / Sluice gate 315
30 Operator Crusher / Conveyor / Mucker 315
31 Operator Tipper / Dumper / Transit mixer 355
32 Operator Concrete vibrator 315
33 Operator Vibratory plain / pad foot roller 315
34 Operator Wagon drill / Drifter 355
35 Painter Cl- I 350
36 Plumber / Pipe fitter 350
37 Sarang / Khalasi 315
38 Spun pipe moulder 315
39 Stone chiseller CI- I / Stone cutter Cl- l 315
40 Struct. steel Fabricator / Marker / Erector 355
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41 Welder / Gas Cutter 315
42 Welder (X-ray quality) 355
II. Semi skilled category
1. Asphalt Sprayer / Boiler attendant 285
2. Bhisti 285
3. Boatman with boat 300
Common SoR 2012:13
281
Sl
No.
Category of worker
S. Rate
for
2012-13
1 2 3
4 Carpenter Cl- II / Erector shuttering 285
5 Cartman with double bullock cart 330
6 Cartman with single bullock cart 310
7 Chavali / Navagani 285
8 Crowbarman / Jumper man 285
9 Fitter Cl- II 285
10 Gang man / Head / Survey mazdoor 285
11 Gardener / Trained mali 285
12 Helper Air compressor / DG set 285
13 Helper Batching plant 285
14 Helper Blasting 285
15 Helper Bus/ Ambulance/ Lorry/ Tanker 285
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201Paper - II Estimating and Costing
16 Helper Bending/Shearing/Planing machine 285
17 Helper Carpenter 285
18 Helper Concrete / Asphalt mixer 285
19 Helper Concrete / Asphalt paver 285
20 Helper Core drilling machine 285
21 Helper Crane/ Tower crane/ Cable way 285
22 Helper Drilling jumbo / Loco / Winch 285
23 Helper Fitter / Fabrication/Electrician 285
24 Helper Grouting/ Guniting/ Shotcreting 285
25 Helper Jack hammer / Pneumatic tamper 285
26 Helper Laboratory / Instrumentation 285
27 Helper Road roller 285
28 Helper Shovel / Scraper / Dozer 285
29 Helper Crusher / Conveyor / Mucker 285
30 Helper Tipper / Dumper/ Transit mixer 285
31 Helper Vibrator 285
Common SoR 2012:13
282
Sl
No.
Category of worker
S. Rate
for
2012-13
1 2 3
32 Helper Vibratory plain/ pad foot roller 285
33 Helper Wagon drill/ Drifter 285
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34 Lineman Electric / Telephone 285
35 Mason Cl- ll / Brick layer Cl-II 285
36 Mechanic Cl- II 285
37 Painter Cl- II 300
38 Patkari / Neeraganti / Sowdy 285
39 Stone Chiseller Cl- II 285
40 Stone breaker / Hammer man 285
41 Valve man / Canal sluice operator 285
III. Un-skilled category
1 Cement / Asphalt handling mazdoor 250
2 Civic worker 250
3 Heavy mazdoor 250
4 Light mazdoor 250
5 Watchman 250
IV. Other category
1 Care-taker / conductor / Lift Attender 300
2 Cook / Mess man 300
3 Dhobi 300
4 Diploma Engineer / Surveyor 450
5 Diver with headgear 365
6 Graduate / Laboratory Assistant 350
7 Graduate Engineer/ Geologist 600
8 Horticulture Assistant / Photographer 300
9 ITI certificate holder / Tracer / Printer 350
10 Literate mazdoor 285
11 Stenographer / Computer Operator 400
Common SoR 2012:13
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283
Sl
No.
Category of worker
S. Rate
for
2012-13
1 2 3
12 Telephone / Wireless Operator 350
13 Typist / Job Typist 350
14
CAD operator with Diploma in Engineering/General degree with
CAD certificate
500
15 Jeep Driver 355
16 Data Processing Operator 500
Note : 1. The wage should not be less than the minimum wages of
schedule of employment,
Subject to out turn. 2. 25% extra over the corresponding labour
rates in respect of the work to be
Done during night time subject to issue of certificate accordingly by
the concerned estimate.
Sanctioning authority for providing in the data and by concerned
Executive Engineer in charge of the work for payment. The night time
allowance is applicable only to the works done under Greater
Hyderabad Municipal Corporation, Greater Visakhapatnam Municipal
Corporation and Vijayawada Municipal Corporation limits only.of
various government agencies.
Transport cost includes cost of transporting the material from source
to the site. In S.S.R., the cost of transporting on a mettaled road is
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given. If transport is required on a cart track or a sand track, to reach
the site, that distance is converted to equivalent metalled road.
Distance on cart track = Distance on metalled road x 1.1
Distance on sand track = Distance on metalled road x 1.4
Stacking includes placing the material in a specified heap for a given
volume in the case of materials like sand and coarse aggregate. Bricks are stacked
for a given number. Sometimes are stacking charges are included in loading and
unloading. Loading and unloading charges are fixed for a given volume or weight
for different materials.
The cost of labor wages for each category of labor are given above as
per Standard schedule of rates 2012-13.
Standard schedule of rates : In standard schedule of rates (S.S.R.) ,
the rates of various materials, machinery and hiring charges and wages of labor
are prepared. It is prepared by the board of chief engineers and approve it for
that year.
5.4 Concept of lead and lift- leads statement
The distance between the source of material to the worksite is known
as the lead. This lead distance changes from one project to another project
depending upon the location. The vertical height through which the material is to
be disposed is known as the lift.
Lead charges : The conveyance charges of the materials from sourceto the site of work is called lead charge. In S.S.R. the lead charges are given for
Metalled roads. The equivalent distance of metalled road for cart track = 1.1xlead,
while for sandy track = 1.4xlead.
Lead statement :Lead statement gives the cost of various materials at
site. It includes basic rate, plus conveyance, blasting charges, seignorage charges
etc.
Lead Statement
S.
No
Mat-
erial
Source Unit Cost at
source
Lead
inKm.
Equi
valentmetal
led
road
Blas
tingchar
ges
Seign
oragechar
ges
Cess
charges
Cru
shingchar
ges
Deduc
tionsif any
Net
rateat
site
Re
marks
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205Paper - II Estimating and Costing
5.5 Preparation of unit rates for finished items of works
Cost of sand as per S.S.R. : For concrete = Rs. 375., For filling =Rs. 288., For plastering = Rs.490.
Cost of cement = Rs. 5100/ton., = Rs. 255 per bag.
Mixing charges for mixing 1 m3 of mortar = Rs. 85.
Cost of preparation of 1 m3 mortar for different proportions
5.5.1. Cement concrete in foundation (1:5:10)1
Quantity of cement =(1.52/16)x1=0.095 m3=0.095x1440/50=2.74
bags.
Quantity of sand = (1.52/16)x5=0.475 m3
Quantity of aggregate = (1.52/16)x10=0.95 m3.
Cost of cement = Rs.255 per bag., Cost of sand=Rs. 375/m3., Cost of
Coarse aggregate=Rs.588/m3.
Cost of
sand
Rs. 323.40
Rs. 367.
50
Rs. 392.
00
Rs. 406.
70
Rs.419.95
Rs. 436.10
Rs. 445.9
Mix
-ing
charges
Rs.85
Rs.85
Rs.85
Rs.85
Rs.85
Rs.85
Rs.85
Mix
propor
-tion
1:2
1:3
1:4
1:5
1:6
1:8
1:10
Quantity of
cement in
bags
9.5 bags
7.2
5.76
4.79
4.11
3.19
2.62
Quantity
of sand
in m3
0.66
0.75
0.8
0.83
0.857
0.89
0.91
Cost of
cement
Rs.2422.50
Rs. 1836.
00
Rs. 1469.
00
Rs. 1221.
50
Rs.1048.
05
Rs.813.
45
Rs.668.
10
Total cost
2831.50
2288.50
1946.00
1713.20
1553.00
1334.55
1199.00
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Construction Technology206
R.C.C. (1:2:4) works in Beams, slab, columns etc
Quantity of cement = 1.52x1/7=0.217 m3 =0.217x1440/50=6.25 bags.
Quantity of sand = 1.52x2/7=0.434 m3.
Quantity of coarse aggregate = 1.52x4/7=0.869 m3.
Quantity of steel =1.1x78.5/100=0.86quintals=86.35 kgs.
Centering and scaffolding charges with casurina ballies, bamboos,
wooden reapers, poles etc.
Lintel = Rs. 1215/m3; Sunshades = Rs. 214/m2., Columns = Rs. 929/
m2., Beams = Rs. 1637/m2.
Slabs up to 150 mm. = Rs. 184/m2.
Particulars
Materials Cement
Sand
Coarse aggregate
Labor: Head mason
Mason
Men mazdoor
Women mazdoor
Waterman
Add 20% for labor
Quantity
2.74 bags
0.475 m3
0.95 m3
0.05 No.
0.15 No.
1.2 NO.
1.8 No.
0.4 No.
Rate
Rs. 255/bag
Rs. 375/m3.
Rs. 588/bag
Rs. 350/No.
Rs. 315/No.
Rs. 250/No.
Rs. 250/No.
Rs. 250/No.
Total
Cost
Rs. 698.70
Rs. 178.15
Rs. 558.60
Rs. 17.50
Rs. 47.25
Rs. 300
Rs. 450
Rs. 100
Rs.182.95
Rs.2533.15
Particulars
R.C.C(1:2:4) including cost of
materials, labour charges,centering charges but excluding
cost of steel and its fabrication.
Materials
Cement
Quantity
6.25 bags
Rate
Rs. 255/bag
Amount
Rs. 1593.75
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207Paper - II Estimating and Costing
Sand
Coarse aggregate
Labour
Head mason
Mason
Men mazdoor
Women mazdoor
Waterman
Total cost of materials & labour
= Rs.2760.30+1274.40=
Rs.4034.70
R.C.C. works in lintel, slab,
beams and columns
Centering charges with
Casuarinas baileys, bamboos,
poles, wall plates etc.
Item
Lintel
Slab
Beam
Column
0.434 m3
0.868 m3
0.05
0.3
1.2 No.
2.0 NO.
0.6 No.
Centering
charges
including
materials and
labourRs.1215
Rs. 1533.33
Rs. 1637
Rs.929
Rs. 375/m3
Rs. 1161.80/m3
Total
Rs. 350/No.
Rs. 315/No.
Rs. 250/No.
Rs. 250/No.
Rs. 250/No.
20% local
allowance
Cost of
materials and
labour
Rs. 4034.70
Rs. 4034.70
Rs. 4034.70
Rs. 4034.70
Rs. 162.75
Rs. 1003.80
Rs. 2760.30
Rs. 17.50
Rs. 94.50
Rs. 300.00
Rs. 500.00
Rs. 150.00
Rs. 1062.00
Rs. 212.40
Rs. 1274.40
Total Cost
Rs. 5249.70
Rs. 5568.00
Rs. 5671.70
Rs. 4963.70
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Construction Technology208
1 m3 of R.C.C. work requires approximately 90 kgs. of steel. The cost
of fabrication of steel including bending and placement in position is Rs. 6.00/
Kg.
5.5.3 Brick masonry in cement mortar
The size of the bricks considered are 19 cmx9 cmx9 cm. The volume
of mortar is 0.32 m3. Cost of brick masonry for 1.0 m3 is considered.
Number of bricks required = 500
Mortar with a proportion of 1:6 is considered.
Quantity of cement = 0.32/7=0.0457 m3=0.0457x1440/50=1.32 bags
Quantity of Sand = 0.32x6/7=0.274 m3
Cost of 1000 no. of bricks 19cmx9cmx9cm as per S.S.R. =Rs. 4687,
Loading and unloading charges=Rs.37.30, Conveyance charges
=118.65+17.80x10=Rs. 297.( for 15 K.M.)
Total cost of bricks = Rs.4687+Rs.37.30+297=Rs.5021.30
Quantity
500 Nos.
1.32 bags
0.274 m3.
Materials cost
0.05 No.
1.0 No.
0.7 NO.
1.0 No.
0.2 No.
Particulars
Brick masonry in
superstructure including cost
of materials and labour
Materials
Bricks
Cement
Sand
Labour
Head mason
Mason
Men mazdoor
Women mazdoor
Waterman
Rate
Rs. 5021.30per
1000 Nos.
Rs. 255 per bag
Rs. 490/m3.
Total
Rs. 350/No.
Rs. 315/No.
Rs. 250/No.
Rs. 250/No.
Rs. 250/No.
Amount
Rs.2510.65
Rs. 336.60
Rs. 134.30
Rs. 2981.55
Rs. 17.50
Rs. 315.00
Rs. 175.00
Rs. 250.00
Rs. 50.00
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5.5.4 Course rubble stone masonry(CRS) in cement mortar
Quantity of stone required = 1.25 m3. Volume of mortar required=40%=0.4.
Quantity of cement required for C.M. 1:6 = 0.4/7=0.06 m3=0.06x1440/
50=1.8 bags.
Total
Add 20%
Rs. 807.50
Rs.161.50
Rs. 969.00
Rs. 3950.55Materials and Labour
Total Cost
Particulars
Materials
Stone including bond
stone and wastage
Cement
Sand
Labour
Head mason
Mason
Men mazdoor
Women mazdoor
Waterman
Total cost of materials and
labour
Quantity or No.
1.25 m3.
1.8 bags
0.36 m3.
0.05 No.
1.6 No.
1.6 No.
0.8 No.
0.15 No.
Rate
Rs.535.60/m3
Rs. 255/ bag
Rs. 490/m3.
Rs. 350/No.
Rs. 315/No.
Rs. 250/No.
Rs. 250/No.
Rs. 250/No.
Add 20%
allowance
Amount
Rs. 669.5
Rs. 459
Rs. 176.40
Rs. 1304.90
Rs. 17.50
Rs. 504.00
Rs. 400.00
Rs. 200.00
Rs. 37.50
Rs.1159.00
Rs. 231.80
Rs. 1390.80
Rs. 2695.70
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Construction Technology210
Quantity of sand= 0.36 m3. Cost of rubble stone =
Rs.293+Rs.74.60+11.20x15 = Rs. 535.60 for a conveyance of 20 K.M.
5.5.5 Plastering
External plastering 20 mm. thick and Internal plastering 12 mm. thick.
Materials for 20 mm. thick plastering in a wall of 100 sq. m.
Volume of plastering = 100x20/1000=2.0 m3.
Add 20% for wet volume and increasing 25% dry
volume=2.0+0.4+0.6=3.0 m3.
Cost of 1:6 cement mortar = Rs. 1553.00/m3. Cost of 3.0 m3 cement
mortar=1553.00x3=Rs.4659.00
Labour charges : Head mason =1/3 no. Cost=(1/3)x350=Rs. 116.70
Mason=12 Nos. Cost=10x315=Rs. 3150.00 Men mazdoor=15 Nos.
= 15x250= Rs. 3750.00
Waterman= No. Cost = (3/4)x250=Rs. 187.50.
Cost of labour = Rs.116.70+Rs. 3150+Rs.3750.00+Rs. 187.50= Rs.
7204.20 Add 20% allowance =Rs. 1440.80. Total
cost of labour = Rs. 7204.20+1440.80=Rs. 8645.00
Total cost of external plastering=Rs.4659.00+ Rs. 8645.00=Rs.
13304.00Cost of 20 mm. thick plastering/m2 = 13304.00/100= Rs.133.04
Materials for internal plastering 12 mm. thick for 100 m2.
Volume of plastering= 100x12/1000=1.2 m3. Add 30% for uneven
surfaces and 25% for dry volume.
Total volume of plastering = 1.2+0.36+0.29=1.95 m3. say 2.0 m3.
Cost of 1:6 cement mortar for 1 m3= Rs. 1553.00 Cost of 2.0 m3
mortar = 2x1553.00= Rs.3106.00
Labour charges = Rs. 8645.00.
Total cost of plastering 12 mm. thick = Rs. 3106.00+ Rs.8645.00=Rs.
11751.00
Cost of plastering 12 mm thick per m2= 11751/100=Rs. 117.51
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211Paper - II Estimating and Costing
5.5.6 Pointing in cement mortar
For pointing in brickwork the total dry volume of materials is taken as
0.60 m3 for 100 m2.
Pointing with cement mortar of proportion 1:2 : Dry volume of mortar
= 0.60 m3
Cost of mortar 1:2 for 1 m3=Rs. 2831.50. Cost of 0.6 m3 mortar =
0.6x2831.50=Rs. 1699.00
Labour :Head mason (1/3)x350=Rs. 116.70
Mason = 10x315=Rs.3150.00; Men mazdoor=10x250=Rs.2500.00;
Waterman=0.5x250=Rs. 125.00
l Cost of labour = 116.70+3150+2500+125.00=Rs. 5891.70
Add 20% allowance=Rs.1178.30; Total cost = 5891.70+1178.30=
Rs.7070.00
Total cost of materials and labour = 1699.00+7070.00=Rs.8769.00
Cost of pointing per m2= 8769.00/100=Rs. 87.70
5.5.7. Cement concrete flooring
Considering 2.5 cm. thick concrete for an area of floor = 100 m2.
Volume of concrete floor = 100x2.5/100=2.5 m3. Add 10% for
unevenness of concrete
Quantity of concrete = 2.5+0.25=2.75 m3. Add 50% for dry volume
of concrete=1.375 m3.
Total quantity of concrete= 2.75+1.375=4.125 m3.
Quantity of cement required = 4.125/7=0.60 m3.=0.6x1440/50=18
bags.
Quantity of sand= 0.6x2=1.2 m3. Quantity of stone aggregate = 0.6x4
= 2.4 m3.
Cement for surface finishing = 100x2/1000=0.2 m3. = 0.2x1440/50=6bags.
Cost of cement= Rs. 255/ bag; Cost of sand= Rs. 490/m3.; Cost of
aggregate = Rs.1161.80/m3.
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Construction Technology212
Cost of cement concrete flooring per sq. meter = 17491.00/100=Rs.174.91/sq m.
5.5.8. Doors and windows paneled and glazed
Consider preparation of door frame with Sal wood . The size of the
door is 1.00 m. x 2.00 m.
Particulars
Materials
Stone aggregate
Sand (coarse)
Cement
Cement for surface
finishing
Labour etc.
Head mason
Mason
Men mazdoor
Women mazdoor
Waterman
Total cost of materials
Total cost of labour
Side forms for finishing
Quantity or No.
2.40 m3.
1.20 m3.
18 bags
6 bags
no.
10 Nos.
5 Nos.
5 Nos.
2 Nos.
Add 20% extra
Side forms
Rate per
Rs. 1161.80/m3.
Rs. 490/m3.
Rs. 255/ bag
Rs. 255/ bag
Rs. 350/day
Rs. 315/day
Rs. 250/day
Rs. 250/day
Rs. 250/day
Lump sum
Lump sum
Total cost
Amount
Rs. 2788.40
Rs. 588.00
Rs. 4590.00
Rs.1530.00
Rs. 9496.40
Rs. 262.50
Rs. 3150.00
Rs. 1250.00
Rs.1250.00
Rs.500.00
Rs. 6412.50
Rs.1282.50
Rs. 7695.00
Rs. 300.00
Rs. 9496.40
Rs. 7695.00
Rs. 300.00
Rs.17491.00
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213Paper - II Estimating and Costing
Materials :Teakwood of cross section 8 cmx12 cm.
Length of the frame = 2x( 2.14+1.2)=6.68 m. Quantity of
timber=6.68x0.08x0.12=0.064 m3.
Add 5% for wastage = 0.0032 m3. Total quantity of timber
=0.064+0.0032=0.0672 m3.
Rate of sal wood = Rs. 40012.00/m3.
Cost of timber = 0.0672x40012.00= Rs. 2688.80
Labour : Head carpenter =1/16 No. Cost =350x1/16= Rs.21.90
Carpenter =1/4 No. Cost =315x1/4= Rs.78.75
Men mazdoor = No. Cost =250x1/2= Rs.125.00Cost of labour Rs.225.65
Add 20% allowance Rs.45.20
Total cost of labour Rs.270.85
Total cost of materials and labour = Rs. 2688.80+Rs.
270.85=Rs.2959.65 say Rs. 2960.00
Width of the plank=1.0-0.10-0.10-0.10=0.6 m. (Width of the stiles)
Length of the plank = 2.0-0.10-0.10-0.10-0.15-0.10=1.55 m. (width
of top, frieze, lock and bottom rails
Unit rate of 40 mm. thick paneled door shutter of size 1.0x2.0 sq m.
double door in teak wood.
AmountParticulars
Materials:-
timber
Stiles
Top railFrieze rail
Lock rail
Bottom
rail
No.
4
1
1
1
1
L
2.00
1.00
1.00
1.00
1.00
B
0.10
0.10
0.10
0.15
0.10
Thick
ness
0.04
0.04
0.04
0.04
0.04
Quantity/
Nos.
0.032
0.004
0.004
0.006
0.004
Rate
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Construction Technology214
Planks for
panels
Brass
accessories
Tower bolt
30 cm.
Tower bolt
15 cm.
Handle 10
cm.
Hinges
Aldrop 30
cm.
Door
stopper
Labour
Head
carpenter
Carpenter
Helpers
1
1No.
1No.
2.no
6.no
1 No.
1 No.
1/15
No.
4 Nos.
1.55
Add
5%
0.6
for
Cost
0.025
wastage
Of
0.023
0.073
0.00365
0.0767 m3
1 No.
1 No.
2 Nos.
6 Nos.
1 No.
1 No.
accessories
1/15 No.
4 Nos.
2 Nos.
Rs.1054
86.00/m3
Rs.248
.00/No.
Rs.121.00/
No.
Rs.337.00/
No..
Rs.112.00/
No.
Rs.
729.00/No.
Rs.
146.00/
No.
Rs. 350/
day
Rs. 315/day
Rs. 250/
day
Rs.8090.80
Rs. 248.00
Rs.121.00
Rs.674.00
Rs. 672.00
Rs. 729.00
Rs.146.00
Rs.2590.00
Rs. 23.35
Rs.1260.00
Rs.500.00
Rs.
1783.35
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Cost of materials = Rs. 8090.80
Cost of brass accessories=Rs.2590.00
Cost of labour = Rs. 2140.00
Total cost = Rs.12820.80
Summary
Specification defines the nature and class of work, materials to be used
in the work, workmanship etc.
Cost of materials at the source : The amount required to purchase
the materials at the source of its production is the cost of materials at the source.
Cost of materials at the site = Cost of materials at the source + Seignories
+ Taxes + Royalties + Transport + Loading + unloading etc.
Cost of transport on metal led road is given in the S.S.R.
Distance on cart track = 1.1 x Distance on metal led road
Distance on sand track = 1.4 x Distance on metal led road
Standard Schedule of Rates (S.S.R.) :Standard schedule of rates
consists of the rates of materials, machinery, hiring charges and wages of labour.
It is prepared by the board of chief engineers and approved for that year.
Lead and Lift : The horizontal distance between the source of the
material to the work site is known as the lead. The vertical height through which
the material is lifted is known as the lift.
Lead Statement :The statement in detail of the cost of materials at the
site is known as the lead statement.
Quantity of materials in Plain cement concrete (1:5:10) :
Quantity of cement = 1.52 x 1/16 = 0.095 cu m. = 0.095 x 1440/50 =
2.74 bags
Quantity of sand = 1.52 x 5/16 = 0.475 cu m.
Add 20%
extraTotal
Rs. 356.65
Rs. 2140.00
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Construction Technology216
Quantity of coarse aggregate = 1.52 x 10/16 = 0.95 cu m.
Brick masonry in cement mortar for 1.0 cu m.
Number of bricks of size 19 cm. x 9 cm. x 9 cm. = 500
Volume of mortar = 0.32 cu m.
Course rubble masonry :
Quantity of stone = 1.25 cu m.
Volume of mortar = 0.40 cu m.
Plastering 20 mm. thick : The volume of cement sand mortar required
for an area of 100 sq m. and a thickness of 20 mm. is 3.0 cu m.
Plastering 12 mm. thick :The volume of cement sand mortar requiredfor an area of 100 sq m. and a thickness of 12 mm. is 2.0 cu m.
Pointing : The volume of cement sand mortar required for pointing of
an area of 100 sq m. with a mix proportion 1:2 is 0.60 cu m.
Short Answer Type Questions
1. Define specification.
2. What is cost of materials at the source.?
3. What is the cost of materials at the site?
4. Write a tabular form for an abstract estimate.
5. List out the various types of labour.
6. Define standard schedule of rates.
7. What is lead and lift?
8. What is a lead statement.
Long Answer Type Questions
1. Prepare specifications for the following
(a) Earthwork in excavation, (b) Cement concrete in foundation, (c) R.R. masonry, (d) Brick work in cement mortar.
2. Find the unit rate for Plain cement concrete (1:6:12)
3. Find the unit rate for course rubble masonry of cement mortar (1:6).
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4. Find the unit rate for brick work in cement mortar (1:6) using standard
size of bricks.
5. Find the unit rate of plastering 12 mm. and 20 mm. thick with a
proportion of (1:5) cement mortar.
O.J.T. Questions
1. Prepare a unit rate of brickwork in cement mortar for 1.0 cu m.
using modular bricks.
2. Prepare a unit rate of R.C.C. (1:2:4) for 1.0 cu m. in slabs, beams
and columns.
3. Find the cost of a door (1.00m. x 2.00 m.) in country wood
4. Find the cost of a window (1.2 m x 1.2 m) in Sal wood.
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Construction Technology218
Structure
6.0 Introduction
6.1 Trapezoidal, Prismoidal, Mid ordinate
6.2 Taking out quantities from L.S. and C.S. in cutting and embankment
Learning Objectives
After studying this unit student will be able to
Calcualate the quantities of earth work in banking and cutting by
Trapezoidal and Prismoidal Rule
6.0 Introduction
All types of roads, railways and irrigation works are constructed over
earthwork. To understand the calculation of earthwork involved in these structures,
these methods of calculation have to be studied in detail.
Cross section of earthwork is in the form of a trapezium. The quantity of
earthwork may be calculated by the following methods.
6UNIT
Earthwork Calculations
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6.1. Trapezoidal, Prismoidal, Mid ordinate
Sectional and mean sectional area methods for calculating earthwork.
Mid sectional area method : In the mid sectional area method, the
average height of the two ends is taken as the mean depth. L is the length of the
section. B is the formation width, and S:1 is the side slope and d1 and d2 are the
height of the embankment at the two ends
Mean height dm = (d1+d2)/2
Area of midsection = Area of rectangular portion+ area of two triangular
portions=Bdm+1/2sdm2+1/2sdm2=Bdm+2dm2.
Quantity of earthwork = (Bdm+sdm2)xL
The quantities of earthwork may be calculated in a tabular form as below
Mean Sectional Area Method : In this method, the area at the ends
of depth d1 and d2 are calculated and the mean area of the section is found.
Sectional are at one end A1 = Bd1+S(d1)2
Sectional area at the other end = Bd2+S(d2)2=A2
The mean sectional area A=(A1+A2)/2
Quantity Q=((A1+A2)/2)xL
The quantities of earthwork may be calculated in a tabular form as follows
Stations Depth
or
Height
Mean
depth or
Height
Central
area Bd
Area of
sides Sd2
Total
sec
tional
area
Bd+Sd2
Length
between
stations L
Quantity
(Bd+Sd2)xL
Embank
ment cutt
ing
Station Height
or depth
Area of
central
port ion
Bd
Area of
s i d e s
Sd2
T o t a l
sectional
a r e a
Bd+Sd2
M e a n
sectional
area
Length
between
stations
L
Quantity
=(Bd+Sd2)
x LBankingCutting
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Construction Technology220
Fig 6.1
Trapezoidal-Prismoidal Formula : In the prismoidal formula the areas
at the ends and the mid sectional area are als