Estimating and Costing

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ESTIMATING AND COSTING D-III CIVIL 1.1 MEANING OF THE TERMSESTIMATING, COSTING AND VALUATION (A) An estimate can be defined as the procedure or method of working out the probable cost of a work. An estimate is prepared by working out the quantities and then calculating the cost suitable rates. Before the construction work of any structure is started, calculation, of quantities of various items of work and its probable cost is done. This is known as estimating. Before starting any civil engineering works or project it is necessary to know its approximate cost by calculating quantity of various items and multiplying it by unit rates of materials. As far as quantity calculation part of estimating is concerned is done by studying and analysis of drawing and specification. Estimate of a work is governed by quantity and quality aspect. Quantity is related with drawings and quality is related with specification for materials and workmanship. Estimates are prepared in standard forms known as: 1. Measurement sheets. 2. Abstract sheets. (B) Costing is defined as the determination of actual cost of the before the execution of it. To know the cost of work detail estimate is prepared and measurement sheet and the probable cost of various items entered in the abstract form. (c) Valuation is defined as the procedure of finding out the value or fair price of a property, such as building, land, a factory, any machine, etc. By valuation present value of property is determined which may depend upon the life of property, maintenance, location, legal control. Purpose of Estimating and Costing: Before taking up any project for execution the owner should know the total cost of the work, so that financial arrangements can be made well in advance. From estimate the quantities of various materials required may be worked and necessary arrangements for the same can be made. The estimate also gives rough idea of the time required for completion of work.

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The number and kind of workers of different categories required to complete the work in the specified time can be found out. An estimate is immensely useful in planning and execution of any work. 1. To know the approximate cost of work. 2. To know the approximate quantity of various materials and labors required. 3. For technical sanction of the project. 4. For inviting tenders and to arrange contract. 5. To have an idea about the time of completion of project. 6. To give an idea for keeping control over expenditure during construction. Purpose of costing 1. To determine probable cost of work before execution. 2. It helps in financial planning to owner before going for construction. 3. Costing of various items required for constriction of structures is known well in advance and accordingly arrangement of finance can be made. 4. Addition and alterations in planning and designing can be done if the costing goes beyond the capacity. TYPES OF ESTIMATE The following are the different types of estimate: 1. Preliminary estimate or Approximate or Abstract or Rough cost estimate 2. Plinth area estimate. 3. Cube rate estimate or Cubical content estimate. 4. Approximate quantity method estimate. 5. Detailed estimate or item rate estimate. 6. Revised estimate. 7. Supplementary estimate. 8. Supplementary and revised estimate. 9. Annual repair and Annual maintenance estimate (A.R. and A.M.) 2

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1. Approximate Estimate: It is required for preliminary studies of various aspects of a work or project to decide the financial position and policy for administration sanction by the competent authority like Municipal Corporation, development authority, etc. In case of commercial projects as Irrigation, Residential buildings, and other similar projects which earn revenue income, the probable income may be worked out. From the preliminary estimate the approximate cost may be known and then income and cost is studied. If it is justified to go for project then further detailed estimates are prepared. In case of non-commercial projects or project which does not give direct return, necessity, utility and money available can be studied. In this type of estimate all important works like cost of land, cost of each building, cost of roads, etc. are shown separately. Example: 1. Approximate cost of a hostel building for 100 students @ 10,000/- Rs. Per student is Rs. 10 lakhs. 2. Approximate cost of 100 bed hospital @ Rs. 50,000/- per bed comes to Rs. 50 lakhs. The approximate estimate is prepared from the practical knowledge and cost of similar works carried out by the P.W.D. or by an Architect. Along with the estimate, a brief report explaining the necessity and utility of the project, and showing how the cost is met with should be accompanied. A site plan also should accompany the estimate. The preliminary estimate can be prepared by various methods for structures. (a) Buildings- service unit basis: Each building is constructed to serve same purpose. For example, a hospital is designed to accommodate certain number of beds. Each bed is then considered as service unit of a hospital building. Whenever a building is constructed the engineer keeps the record of the place of construction actual cost of construction number of service units, etc. From this record it is possible to work out the cost of construction, number of service units, etc. From this record it is possible to work out the cost of construction per service unit. Cost of construction per service Unit =


     
 .    

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The costs worked out by this method are very approximate and will vary considerably with buildings of different shapes and sizes, kind of construction and locality. Example: Approximate cost of 100 bed hospital @ Rs. 30,000/- per bed comes to Rs. 30 lakhs. (b) Irrigation projects: After studying the topo sheet the dam site is marked and the catchment area is found out. Considering the total rain fall and percentage of total available yield, the capacity of reservoir is worked out. The final stage is to decide upon the cost of similar per million cubic meters of the storage with the help of records of construction costs of similar projects by P.W.D. By multiplying this cost with the total storage capacity, approximate cost is worked out. (c) Water supply and sewerage projects: On the basis of per head of population served, approximate cost of water supply project for a population of 1 lakh people @ Rs. 80 per head works out to be Rs. 80 lakhs. (d) For highways: Per kilometer basis, depending upon the nature of road, thickness and width of metalling, for 5 kilometers at Rs. 2 lakhs per 1 k.m., works out to Rs. 10 lakhs. Other factors to be considered in case of approximate estimate of highway are: (i) Land to be acquired. (ii) Width and type of wearing surface of road. (iii) Other construction details to be provided for a particular class of road. (iv) Information about road works already constructed and the cost per kilometer. (v) Earth work. (e) Hostel: Approximate estimate is calculated on the basis of per person. (f) Per seat in a stadium. (g) Per seat in a stadium. (h) Per bed in a hospital. 2. Plinth Area Estimate: This estimate is prepared on the basis of plinth of building. The rate for unit plinth area is determined from the cost of similar building having similar specifications, heights, construction and locality. Plinth area estimate is prepared by finding the plinth area of the building and multiplying by the plinth area rate.

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Plinth area should be calculated for the covered area by taking the external dimensions of building at the floor level. This area must not include area of court yard, open passages, etc. For a multistoried building the plinth area estimate is prepared for each storey separately. Plinth area estimate is a type of approximate estimate. Rate of construction on plinth area basis =

       

Example: Approximate cost of a building having plinth area of 100 sq.m. @ 900/- per sq.m. Works out as Rs. 90,000/-. 3. Cube Rate Estimate: It is an approximate. It is prepared on the basis of cubical content of the building. The cube rate is determined from the cost of similar building having similar specification and construction in the locality. This is calculated by finding the cubical content of the building (l

 and multiplying it by cube rate. It is more accurate as compared to plinth area estimate. The cubical content of building must not include foundation, plinth and parapet above roof. Rate of construction on cube rate basis =

          

Example: Approximate cost of a building of cubic content (vol.) of 400 cu.m. @ 180/-Rs. Per cu.m works out as Rs. 72,000/-. 4. Approximate Quantity Method Estimate: In this method approximate total length of walls is found in running meter (RMT) and this total length multiplied by the rate per running meter of wall. For this a structure is divided into two parts: 1. Foundation (including plinth). 2. Super structure. The running meter cost for foundation and super structure should be calculated first and then running meter rate should be multiplied by total length of walls. For this method plan of building must be available. 1.2.1 Approximate Estimates Approximates estimate is made to find out an approximate cost in a short time, without taking out actual quantities. This enables the responsible authority to consider the financial aspect of 5

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the scheme. The accuracy of the cost estimated by such approximate estimate depends upon the judgment, skill and experience of the estimator and upon the correctness of the prices. 1.2.2 Uses The approximate estimates are prepared to serve the following purposes: 1. To give rough idea of the probable expenditure: Before taking up any project, it is necessary to ascertain whether it can be feasible or financed. For this a rough idea of the probable expenditure has to be obtained. If this appears feasible, then further details may be obtained. 2. Administrative approval: In case of government and other public works, proper sanction has to be obtained for allocating the expenditure required for the detailed investigations and preparation of plans and estimates. This sanction is given on the basis of approximate cost found out by approximate method. 3. Valuation and rent fixation: Sometimes it is necessary to find out the cost of an existing structure (a) Sale or purchase, (b) Rent fixation, (c) Framing tax schedules, and (d) Insurance requirement. In all these cases the values invariably make use of the approximate estimate. 1.2.3 Methods of Approximate Estimates Approximate estimate is prepared to decide the financial aspect, administrative approval, for sending the proposal and appraisal of various civil engineering projects. For different type of structures like buildings, roads, bridges, railways, etc; approximate estimate is prepared from practical knowledge and cost of similar works executed in past. It shows separately cost of land, building, road, water supply, sanitary work etc. 1.2.4 Preparing Approximate Estimates for Buildings There are four methods to find approximate estimate of building: 1. Service unit method, 2. Plinth area method, 3. Cube rate method, and 6

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4. Approximate quantity method. 1. Service unit method or per unit method: Per student for hostel, per student for schools, per class room for schools, per bed for hospitals, per seat for cinema halls, per bay for factories, I,e, estimate prepared by considering the service unit of it. Cost of construction per unit =


    
      

Such estimates are very approximates and varies according to shapes, size, type of construction and locality. Example: Approximate cost of a 100 bed hospital @ 40,000/- Rs. Per bed works out as Rs. 40 lakhs. 2. Plinth area method: If the plan of the building is not ready or available at the beginning. Then just to prepare the proposal, floor area of rooms etc. May be determined from the requirement and 30 to 40% of the total area thus found is added for walls, circulation and waste to get the approximate total plinth area. Now plinth area is multiplied by the plinth are rate which gives approximate cost of the building. This estimate is more accurate then service unit method. Example: The building having plinth area of 100 sq.m. @ Rs. 400/- per sq. m. works out as Rs. 40,000/-. 3. Cube rate method: Rate of construction is calculated on basis of construction cost of an existing building and dividing it by volume of building. The approximate cost of building of cubic content (Vol.) of 200 cu.m. @ Rs. 150/- per cu.m. Comes to Rs. 30,000/4. Approximate quantity method: To find the running meter rate of foundation, the approximate qualities of items such as excavation, foundation, brick work up to plinth, D.P.C., are calculate per running meter of walls. By calculating price per running meter, rate is determined. Similarly for super structure also the price or rate per running meter is determined for approximate quantities of brick work, wood work, roofs, floors, etc. For this method plan of building must be available. 1.2.5 Preparing Approximate Estimates for Roads and Highways The unit to be adopted to determine approximate cost of new proposed highway is per km or per mile basis. The cost of road per km depends upon nature of road (national or state highway or village road, etc.) Width of road, thickness of metal ling, pavement surface, temporary and permanent acquisition of land, topography and cross drainage works. Thus by knowing the cost of construction per 7

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km length of a similar road, approximate estimate of proposed road can be prepared. For example state highway of 10 km is constructed in Rs. 20, 00,000/-. Therefore, approximate cost per km length is Rs. 2, 00,000/1.2.6 Approximate Estimate of “Railway project” For estimate of a railway project main items or work are foundations, embankment in cutting and banking, bridges, culverts. Level and road crossing, fencing, boundary, km. post, gradient post, office building, platform, staff quarters, workshops, sanitary arrangements, etc. Railway estimates are prepared by knowing the cost per km. of recently constructed similar railway line i.e. Same gauge, sleeper, ballast, etc. while preparing approximate estimate, cost of land acquisition should also be included. Typical Approximate Estimate Sr. No. 1. 2. 3. 4. 5. 6 7 8. 9. 10. 11 12 13 14 15

Particulars Qty. Rate Rs. Preliminary works, 1km 10,000 surveying, etc. Land: Permanent 1km 90,000 Temporary 1km 40,000 Foundation 1km 1,60,000 Bridges 1km 5,50,000 Level and road crossing 1km 34,000 Fencing 1km 10,000 Boundary and gradient 14,000 posts 1km Ballast- below sleeper Main line Siding 1km 5,00,000 Track, including laying 1km 14,000 Signal lines and telegraph 1km 18,00,000 lines Station platform 1km 40,000 Station building 60,000 Office furniture 12,00,000 Service roads L.S. 2,50,000 Misc. L.S. 40,000 Total Add for contingencies 3% Add for supervision and establishment 10% Grand Total

Cost Rs. 10,000

90,000 40,000 1,60,000 5,50,000 34,000 10,000 14,000

5,00,000 14,000 18,00,000 40,000 60,000 12,00,000 2,50,000 40,000 48,16,000 1,44,480 4,81,600 54,42,080

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1.2.7 Preparing Approximate Estimates for Bridges and Culverts Approximate estimate of bridges are prepared on the basis of per running meter of span or per running meter of linear water way. Approximate estimate of bridge depends upon road way, nature of bridge, depth and type of foundation, etc. Approximate cost of new proposed bridge is worked out by determining total no of spans or total length of linear water way and multiplying it by rate of construction per meter length of a recently constructed similar bridge with the similar specifications. For culverts approximate cost may be determined per meter of span. Per meter of linear water way or per no of culvert of different span. Approximate cost of bridge and culvert can also be worked out according to sub-structure and super structure respectively. For example approximate cost of bridge having 3 spans of 50 meter each, comes out to be Rs. 25,00,000/- at a rate of Rs. 20,000/- per running meter of span. In short, approximate estimate of a bridge can be calculated as below: 1. Find linear water ways during the time of floods. 2. The known cost of construction of a similar bridge is divided by its linear water ways to find out the rate of construction per meter of linear water ways. 3. Multiply this total linear water ways at the site with the rate of construction per meter of linear water ways. It will be the approximate cost of bridge. By dividing the bridge in two parts i.e. sub-structure and super-structure, approximate cost can be found out separately. 1.2.8 Preparing Approximate Estimates for Irrigation Projects Approximate estimate of irrigation project is determined by considering approximate estimate of storage reservoir, dam and canals. For storage reservoir and dam, estimate is prepared on the basis of per million cubic meters of storage capacity or per sq. mt. of catchment area. For canals, per km basis or per cubic meter capacity of canal or per hectare of commanded area, approximate estimate is prepared. Examples: 1. Approximate cost of 10 km long irrigation canal is Rs. 10 lakhs at a rate of Rs. 1, 00,000/per km. 2. For an irrigation project of commanded area 2000 hectares approximate estimate is Rs. 80lakhs at a rate of Rs. 4,000/- per hectare.

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1.2.9 Preparing Approximate Estimates for Water supply The basis of preparing approximate estimate of water supply project is the population to be served by this project. Thus, by knowing cost of water supply works per capita from similar project already executed approximate cost of a new project can be worked out. Sometimes approximate estimate for this project is also prepared on the basis of area covered i.e. per hectare basis. For example approximate cost of water supply project for a population of 70,000 at a rate of Rs. 120/- precipitin comes out to be Rs. 84,00,000/For overhead water tank: On the basis of capacity, per litre (gallon) of tank depending on the type of structure, height of tank etc. Approximate cost of an overhead R.C.C. water tank of 50,000 litre capacity @ Rs. 9 per litre works out to Rs. 4.5 lakh. Preparation of estimate includes the following: 1. Data collection: Situation or location, configuration, rain fall, population, existing water supply, existing drainage system, necessity of scheme, etc. 2. Estimation of cost of project: (a) Preliminary survey. (b) Head works. (c) Well and pump house, (d) Inspection well, (e) Pumping machineries, (f) Rising main, (g) G.S.R. (Ground storage Reservoir), (h) Treatment works, (i) E.S.R. (Elevated Service Reservoir), (j) Distribution system, (k) Approach roads, (l) Staff quarters, and 10

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(m) Land acquisition. 1.2.10 Preparing Approximate Estimates for Drainage Approximate estimate of sewerage project is prepared on the basis of per head of population to be served by taking help of rates per capita from a similar sanitary project already executed or on the basis of area covered by drainage lines i.e. per hectare basis. Example: Approximate cost of a sewerage project for population of 50,000 souls comes to Rs. 60 lakhs at a rate of Rs. 120/- per head. 1.2.11 Preparing Approximate Estimates for Storage Reservoirs and Dams Per million cubic meter of storage capacity: This is a quick method of estimating cost of a scheme without carrying out any survey or preparation of drawings. The method consists of following steps: 1. Selection of suitable site with the help of topo-sheets. 2. Find the catchment area. 3. Find rain fall data from rain gauge station near catchment area. 4. Capacity of reservoir by contours. 5. Decide construction cost per million cu.m. Of storage. 6. By multiplying this cost with the total storage capacity, approximate cost is worked out. 1.3 DEAILED ESTIMATES It is an accurate estimate and consists of working out the quantities of each item of work and working out the cost. The dimension, length breadth and height of each item are taken out correctly from drawing and quantities of each item are determined. Then abstracting and billing is done. A detailed estimate is prepared in two stages: 1. Details of measurement and calculation of quantities. 2. Abstract of estimated cost. Details of measurements of each item of work are taken from plan and drawings and calculated in measurement sheet. Abstract is prepared by determining cost of each item of work. The rates of different items are taken from schedule of rates. 11

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1.3.1 Types of Detailed Estimate There are various types of detailed estimates which are prepared under various conditions of construction of a new or old work. There estimate give accurate amount of items and cost required for it. Various types are as below: (1) Revised estimate. (2) Supplementary estimate (3) Revised and supplementary estimate etc. 1.3.2 Detailed Estimate of a New Work While preparing detailed estimate of a new work various steps are required to be followed by an estimator, like knowing the various items to be executed, study of drawings, study of specifications and rates of various items. For a new work all the items must be described in measurement sheet using specifications and their quantities of work shall be calculated according to dimensions given in drawing. For example if you want to prepare all estimate of a new road, various items will be, clearing the site, construction of sub grade , sub base, base course, wearing coat, mile stone, arboriculture culverts if any, etc. For example detailed estimate of a new residential building will include various items as below. (1) Clearing the site, removing bushes, leveling the plot etc. and complete. (2) Excavation of foundation below ground and leveling the trenches dug with compacting, watering and termite proofing if any, etc. and complete. (3) P.C.C. bedding below foundation in C.M. (1:6), 250 mm thick with proper mixing and compacting, curing etc. and complete. (4) U.C.R. masonry in C.M. (1:5) in plinth and foundation with laying, curing etc. and complete. (5) B.B. M in C.M. (1:6) in super structure with lying bricks, checking line and levels laying mort ant and curing etc. and complete. On the similar guidelines detailed estimate of a new work can be prepared. 1.3.3 Revised Estimate It is a detailed estimate. It is prepared under any one of the following circumstances: 12

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1. When the original sanction estimate exceeded more than 5%. 2. When the expenditure of a work exceeds or likely to exceed the amount of administrative sanction by more than 10%. (3) When there are material deviations from the original proposal, even though the cost may be met from the sanctioned amount 1.3.4 Supplementary Estimate It is a detailed estimate and is prepared when works are required to supplement the original works. When further development is required during the progress of work, a fresh detailed estimate is prepared for additional work. The supplementary amount is shown separately in the abstract along with original amount, for sanction. 1.3.5 Supplementary and Revised Estimate When the work is practically abandoned and estimated cost of remaining work is less than 95% of the original work, or less than 90% of the original sanctioned estimate or when there is material deviation and changes in design is there. Then the amount of original estimate is revised by the competent authority. A supplementary and revised estimate is prepared and fresh technical sanction of the competent authority is obtained. 1.3.6 Maintenance and Repair Estimate This is a detailed estimate and it is prepared to maintain the structure or work proper order and in safe condition. For buildings, this includes white washing, colour washing, painting and minor repairs etc For road work, this includes patch work, renewals, repairs of bridges and vulverts. For annual repair of building 1 to 1.5% of the original construction cost of the whole building is provided. These estimates may be on the basis of time of repairs like quadrennial repair estimates, special repair estimates etc. 1.3.7 Uses of Detailed Estimate Detailed estimate is prepared for technical sanction of the project by competent authority, for arranging contract and for execution of work. Solved Examples

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Ex.1: Prepare an approximate estimate of a residential building of plinth area 1000 m2. If the cost of construction of a building with similar specification in locality is Rs. 1,62,00000/for 1800m2 of construction. Solution: Plinth area rate

= =

         

= Rs. 9,000/-per m2 Approximate cost of new residential building = plinth area
 = 1000
9000 = Rs. 9000000/Ex. 2: A hospital building of 150 beds is constructed in Talegaon in the cost of construction of Rs. 25 lacs. Find the approximate estimate of a small hospital of 35 beds in the similar locality by using service unit method. Solution: Rate per service unit

= =

            

Rs. 16666.66 per bed. ∴ Approximate cost of newly proposed hospital of 35 beds = Number of beds
Rate per bed = 35
16666.66 = Rs. 583333.33 Ex. 3: The cost of construction of a college building in Vasai is 1 crores 40 lacs for a capacity of 400 students and cover area of construction about 1800m2. Prepare approximate estimate of a newly proposed college building of 1235 students with the area 7000 m2. Use service unit method and plinth area method. Solution: 14

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(i) Service unit method: Rate of construction per student basis = =

          ! !

= Rs. 35000/-per student ∴ Approximate estimate of new proposed college = Number of student
Rate per student = 1235
35000 = 43225000/= 4 crores, 32 lacs and 25 thousands. (ii) Plinth area method:

    

Rate per m2 of plinth area = "     =

! 

= Rs. 7777.77 per sq.m. ∴ Approximate estimate of new college of 7000m2 = 7777.77
7000 = Rs. 54444444.44 Ex. 4: A residential building of g+4 has been constructed in pune and having a plinth area of 200 m2. Height of building is 16.5 m above ground. The cost of construction of the building is 8000000/- (eighty lacs). Using method of cube rates estimate prepare an estimate of a building of 12 m height and area at plinth 290 m2. It has four floors. Solution: Rate of construction on cube rate basis

= =

            "#! 

= $#.

%

= Rs. 2424.84 per m3 15

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= 2425/Approximate estimate of new building = Rate/ m3
Volume of new building = 2425

 = 2425
290
12 = 84, 39000/∴ Approximate estimate

= Eight four lacs, thirty nine thousands only.

2.1 METHODS OF DETAILED ESTIMATE Detailed estimate of work can be prepared by using following methods: 2.1.1 Unit Quantity Method This estimate can be prepared quick and easily but it requires record of unit quantity rates for similar structures, in same locality with similar specifications. Various departments can maintain unit cost of those works. Other than unit quantity rates following points are considered, (1) Price level variations, (2) specification required, (3) Location of site, (4) Number of units in structure and (5) Foundation and soil conditions etc. This method is used for preparing preliminary estimates. 2.1.2 Total Quantity Method In this method, with the help of detailed drawing total quantity of various items is calculated. Items can be obtained by dividing the whole structure into different components. Now this total quantity of each item is multiplied with the unit rate of respective item, which can be obtained either from schedule of rates or from analysis of that item. This given as estimated cost of that item. On adding amount required for all items we get estimate of whole project. 2.1.3 Data Required For Estimate Following data are necessary for preparing an estimate: 1. Drawing: A detailed drawing showing plan, elevation and section with all the dimensions is essential. 2. Specifications: Specification gives description of materials to be used, mode of execution quality of work etc. The rates of items depend on specification. 3. Rates: The market rates of various items, wages of different categories of labour, cost of different materials should be made available.

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4. Mode of measurement: The units which are commonly used are: (i) for length metre (ii) for area –sq. meter (iii) for volume cubic meter (iv) for capacity-litre (v) for mass –kg. For voluminous works- the length, breadth and height are measured and volume is calculated. The unit of measurement is cubic metre. For long and thin works only the length is measured and unit of measurement is running metre. Statement showing the unit of measurement of different items used in civil engineering works is given below: Units of Measurement: m3, m2, running meter, kg, quintal, tone etc. 1. Earth work

m3

2. P.C.C.

m3

3. R.C.C.

m3

4. Brick work

m3

5. Stone masonry

m3

6. Wood work for door and window frames

m3

7. Door and window shutters

m2

8. Cement concrete grill work

m2

9. 10 cm thick brick wall

m2

10. D.P.C.

m2

11. Plastering and pointing

m2

12. Flooring

m2

13. Skirting

m2 (for 1 tile), RMT (for  tile)

14. Grills and collapsible gate

m2

15. Tiled roofing, A.C. sheets, G.I. sheets

m2

16. Centering and shuttering or form work

m2



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17. Dado

m2

18. Oil paint/colouring

m2

19. Barbed wire fencing

RMT

20. Railing

RMT

21. Pipe

RMT

22. Brick on edge

Numbers

23. W.C. pan/wash basin

Numbers

24. Manhole cover

Numbers

25. Site clearance

Job (Lump sum)

26. Electric wiring

Point

27. M.S. Reinforcement

Kg or Metric Tonne (M. Ton)

28. Timbering of trenches

m2

29. Grouting for crack joints

m2

30. Surface drying

m2

5. Abstract from I.S. 1200: I.S. 1200: The I.S. deals with the method of measurement of buildings and civil engineering works. This Indian standard was adopted by India Standard Institution after the draft finalized by Civil works Measurement sectional Committee and is approved by the civil Engineering Division Council. Measurement has a very important place in the planning and execution of any civil engineering work from the time of estimate to final completion and settlement of payment to the contractors. There are 25 parts in I.S. 1200, each one being published separately. They deal with method of measurement for earth work, brick, stone work, etc. These I.S. codes give rules for rounding off the numerical values; successive rounding number of figures and general rules for measurement of works. The I.S. 1200 guides in preparing the estimates, taking measurements of works and making payments to contractors. Rules for Deductions in Masonry: No deductions shall be made for the following: 18

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(a) Openings upto 0.1m2 in section. (b) Ends of beams, lintels, rafters, purlins up to 0.05m2 in section. (c) Wall plates and bed plates, bearing of slabs and chajjas where the thickness does not exceed 10cm and the bearing does not exend over the full width of wall. From the gross volume of masonry all other openings are deducted. Rules for making Deductions in Plastering and Painting Work: (a) No deductions are made for openings not exceeding 0.5 m2 each and no additions are made for jambs, soffits and sills of these openings. (b) For openings more than 0.5m2 but not exceeding 3 m2, 50% of opening area should be deducted for one face only. No additions are made for jambs, soffits and sills. (c) For openings more than 3 m2, full opening area should be deducted for one face only. Separate additions made of jambs, soffits and sills. Rules for painting work: Painting of doors shall be measured closed and flat in m2. It shall include frames, edges, cleats etc. Different types of doors and windows shall be grouped under one item and they are of uneven surface shall be converted into equivalent area. The multiplying factors for different doors surface are given below: Particulars 1. Panelled, ledged, battened and framed 2. Fully glazed 3. Partly paneled and partly glazed 4. Flush door 5. Louvered door 6. For corrugated sheet 7. Iron bars, grill work

Multiplying factor 1 (for one side)  (for one side)  1 (for one side) 1 (for one side) 1 (for one side ) 1.20 (for one side)  (for one side) 

2.1.4 Factors to be considered during preparation of Detailed Estimate 1. The nature of work: When a construction work is divided in different items of work such as ear work, concrete, brick work, etc. The quantity of items is carefully calculated. If nature of work is large the transportation charges, availability of material and labour should be kept in mind. If nature of work is then use of local materials and labour available should be done. 2. Quantity and availability of material: If quantity of material required is in large amount the concept of bulk purchasing in whole sale should be used, while deciding rates of items.

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3. Transportation of materials: If materials required for project is not available locally the transportation charges should be added to each item while preparing detailed estimate. 4. Location of site: If site is in the remote area or away from city then transportation charges should be include while costing. If site is not approachable then cutting of jungles, construction of pilot road. Arrangement of electricity, transfer of machinery etc. requires a large cost. 5. Labour charges: For preparing detail estimate, local labor charges should be known to estimate. These charges should be revised from time to time depending on locality before preparing detailed estimate 2.1.5 Specification Specification is a statement of particulars for execution of any item of work, its specification must known. Specifications are written by experts of a particular field. In this chapter; necessity, purpose methods of writing specifications and its types are explained in detail, usig suitable example. Necessity and Importance of Specifications: (A) Necessity: A specification is a statement of particulars. An engineering specification contains detailed description of all workmanship and materials which are required to complete an engineering project in accordance with drawing details. The drawings show the proportions and relative positions of the various components of the structure. It is not possible to furnish the information on the drawings regarding the quality of materials to be used and the quality of workmanship to be achieved during construction, due to shortage of space. Thus details regarding materials and workmanship are conveyed in a separate contract document which is known as the specifications of the work. In general, the drawings showed what is to be done, whereas the specifications state how it is to be accomplished. It is understood that the combination of the drawings and specifications will define completely the physical, technical and operating characteristics of the finished project. (B) Importance of Specifications: The conditions of contract often include a statement describing the procedure to be followed in the event of conflict between drawings and specifications: (a) In the event of conflict within drawings the large-scale details shall govern the small scale details. (b) In the event of conflict between the specifications and drawings, the specifications shall govern drawing. 20

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(c) Purpose of Specifications: The structural drawings show the shape and size of the various structural components. It is not possible to give details regarding the quality of materials and the workmanship of each and every items of the work on the drawing itself. The quality of the material and the workmanship or methods of completing the works etc. In detail are furnished in separate document, know as specifications. The specifications are generally written to supplement information shown on drawings. They serve the following purposes: 1. To give the required information for an item of work which cannot be shown on the plan? 2. To help the contractor in giving the necessary quotation for work. 3. For necessary execution of the work, for supervising. Points to be observed in framing the Specifications of an Item: (A) Method of Writing Specifications: The specifications are prepared by Engineer or Architect. While writing the specifications, it is not known who will be the contractor. Therefore, while writing the specifications, care is taken that it should be clearly understood by the supervisors, workmen, contractors, etc. Some of the requirements are stated below: 1. Simple and clear language should be used. Rules of grammar should be adhered to. The wordings should give clear meaning. 2. The specifications should be brief. Long sentences should be avoided. 3. The specifications should be fair to all parties. workmanship should be kept in view.

Practical limitations of materials and

4. When old or standard specifications are used for the preparation of new set, care should be taken to delete inapplicable material. 5. As the specifications are the legal documents, they should be concise as far as possible, because of fewer words will involve less risk or legal difficulties. (B) Specification paragraph: The paragraph of a particular specification should be arranged in the following sequences: 1. Materials that is required for work. 2. Specifications for materials. 3. Preliminary work, before the construction. 21

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4. Procedure for executive the work. 5. Tests, if any. 6. Clearing on completion. 7. Mode of measurements. (C) Legal Aspects of Specifications: Specifications form a part of contract document, without which the contract document becomes invalid on each page of the specifications both the parties i.e., owner and contractor should sign so that these specifications, where clear instructions, regarding the quality and procedure of works etc., are given will be binding on both the parties. If any dispute arises between the parties, the specifications will help the arbitrator or the court to settle the dispute. If the contractor’s work deviates from the specifications, he will be liable for penalty. The specification also mentions the mode of measurements, quality and procedure of item. So, it is binding on both the parties to adhere to it. The contractor cannot ask for extra measurements or owner cannot give less measurements. The general character and the scope of the work in illustrated and defined by the specifications and signed by both parties. So it becomes a legal binding on both the parties to adhere strictly to the agree specifications. In the absence of complete specification, the contractor’s obligation is limited to performance of only what is called for in such incomplete specifications. As such great care has to be taken in preparing specifications. Types of Specifications: The specifications can be broadly classified as: 1. Contract specifications: The specifications written for a particular construction project given contract to accompany the detailed drawings are called contract specifications or project specifications. These are further divided into two groups: (a) General specifications. (b) Particular specifications. 2. Guide specifications: These are prepared to serve as guidelines for preparing project specifications

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3. Standard specifications: Usually, the specifications are standardized for most of works, by the departments. These standard specifications are numbered. After standardizing specifications, it is not necessary to write detailed specifications, with all the contract documents. While preparing the contract document only the serial number of standard specifications is written. This saves time, labor and other expenditures. For example, the Bureau of Indian Standard has prepared volumes of specifications for a wide variely of materials. These standard specifications are also revised from time to include changes in technique while preparing the contract document. 4. Manufacture’s Specifications: Manufactures of building materials or product, publish specifications of their products. These are in the form of standard specifications or Guide specifications. 5. General specifications: General specifications give the nature and type of materials which are to be used in the different items of works. In other words, it is the brief description of various items of work, specifying the materials, qualities, proportions, etc. These give the idea about the whole work, therefore, it is known as general specifications. 6. Detailed specifications: The detailed specifications describe the item of work in details, accurately and complete in all respects in relation to the drawings of the works. The detailed specifications of an item of work specify the quality and quantities of materials, the proportion of mortar, workmanship, and the method of preparation, execution and mode of measurements. The detailed specifications are arranged in the same sequence of order as the work carried out. The detailed specifications form an important part of contract document. Every Engineering Department prepares the detailed specifications of the various items of works and get them printed in a book form known as ‘Detailed Specifications’. When the work is taken up, instead of writing the specifications every time, the printed detailed specifications are referred. 2.1.6 Quantity and Availability of Material While detailed estimate is prepared for any work an estimator must think of quantity of material required for an item and its availability. If a material mentioned in specifications of a work, for an item is not available in market in the required quantity, then the estimator shall take the help of department. He shall discuss the matter with the tender inviting authority and decision can be taken. Sometimes materials required are not available within a reasonable distance from the site of work, and it is required to be transported from a long distance. Then the provision shall be made in the estimate mentioning the place of availability of material required for an item of work. If

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the quantity of material required is in large amount than concept of bulk purchasing shall be used. 2.1.7 Location of Site This is a very important which are suppose to mentioned in the detailed estimate and while abstracting the quantities of items of work, it shall be taken into account. If the site is in remote areas or away from town. Then rates of items shall be taken in abstract sheet by considering location of site. If this point is ignored while preparing the estimate than the cost of detailed estimate will be less than the actual costing of work and that will lead to difficulties to the owner or department as for as finance is concern. If site is not approachable easily then cutting of jungles construction of pilot roads, arrangement of electricity requires huge cost, so that shall be included in abstract sheet. 2.1.8 Labour Component For every item of work an estimator shall think various factors while abstracting the quantities of work. (i) Quantity of material (ii) Location of site (iii) Type of labour required (iv) Costing of labour (v) Special skilled labour required etc. Labour component in the costing plays a very important role because it covers about 30% to 40% of cost of an item. If labour component is not taken in to consideration while preparing detailed estimate than the estimated cost calculated will be less than the actual cost required for a work. A provision of contingencies and work charged establishment shall also be made in an estimate which can compensate any deficiency in an estimate. 2.2 STEPS IN PREPARING DETAILED ESTIMATES Step NO. 1: Divide the whole project or work in various items. Step No. 2: Divide the various items and group them under different sub heads. Stpe No. 3: Enter the detailed of measurement of each item of work in measurements form and calculate the total quantity of each.

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Step No. 4: After the quantities are taken out squaring the dimensions is done. It means the calculation of number, length, are and volumes are entered in last two columns of measurements sheet. There are various methods of squaring the dimensions: (1) Decimal system, (2) Duodecimal system and (3) Fractional part and practice. Now-a-days decimal system is used. All these squared dimensions must be checked by different persons by tick-mark in other colour ink. If any correction is done it must be cross- checked. Step No.5: This is the last step in preparing detailed estimate. The cost under item of work is calculated from the quantities computed at workable rates. These costs along with rates are entered in ‘Abstract Form’. In abstracting 3 to 5% amount of total cost is added for contingencies such as petty expenditure, unforeseen expenditure, changes in design, changes in rates, etc; which may occur during the execution. A percentage of 1భమ to 2% of total cost is added for the expenditure of work charge establishment. The grand total gives the estimated cost of work. 2.2.1 Main Items of work for Detailed Estimate and their Units Main items of work are given below in case of buildings, roads, etc. 1. Earthwork: Earthwork in excavation and in filling should be taken out separately under different types. Foundation trenches are usually dug to the exact width of foundation with vertical sides. Quantity of earthwork is calculated by taking dimensions length, width and height. Earthwork is measured in cubic meter. 2. Bed concrete in foundation: It is calculated by taking length, breadth and thickness of concrete bed; measured in cubic meter. 3. Soiling: When the soil is soft, one layer of brick or stone is laid below the bed concrete. It is in square meter and expressed with specified thickness. 4. D.P. C. (Damp proof course): It is a course provided at the plinth level under the wall for te full width of plinth wall. It is not provided at the sill of door and verandah openings for which deduction is made which calculating length of D.P.C. it is measured in square meter and 

expressed with specified thickness. In general 2.5 cm thick cement concrete (1:1 :3) with water proofing materials is used as O.P.C. 5. Masonry: Masonry for foundation and plinth is taken under one item and masonry for super tracture is taken under separate item. It is computed in cubic meter by taking length, breadth and height. In case of wall footing, masonry for steps is calculated separately and added together. iN buildings having more one floor, the masonry for superstructure for each floor is computed separately. Deductions for openings like doors, windows, cupboards, etc. is done.

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Decution for lintels for openings is also done by taking length, breadth and height. Different types of masonry are taken under separate items. Thin partition walls of thickness less than 10 cm, honeycomb brickwork is taken under separate item in square meter and no deduction for holes is done. 6. Lintel: Lintel are casted in R.C.C. and quantity is calculated in cubic meter. Length of lintel is equal to size of opening plus of 150 mm each on both sides. 7. R.C.C. : R.C.C. Work is calculated for beams, lintels, columns, footing, slabs etc. It is calculated cubic meter, by taking length, breadth and thickness. No deduction for steel is done while calculating the quantity of concrete, which includes centering, shuttering and fixing of reinforcement in position. Reinforcement (quantity of steel) is taken under separate item, including bending and measured in kg, quintals, or in metric tone. If detail drawings are not available 0.8 to 3% of concrete may be taken by volumes as a quantity of steel which is further multiplied by density. Centering and shuttering are usually included in R.C.C. but may also be taken separately in square meter of surface in contact with concrete. In R.C.C. Work, plastering is not taken separately. 8. Flooring: For grounds floor, cement concrete and floor finishing of stone, marble or mosaic tiles taken under one item and quantity is calculated in square meter. For upper floors, bed of R.C.C. is taken cubic meter and other member is calculated in cubic meter. 9. Roof: In Case of roof, flat roofs are calculated in cubic meter like slab and for pitched roof. Quantity of trusses and other members is calculated in cubic meter. In case of roofing material tiles, G.I. sheets or A.C. sheets are measured in square meter. Tiles on hip and valley are measured running meter. 10. Plastering and pointing: Plastering is calculated in square meter and expressed with specified thickness. For masonry the measurements are taken for whole face of wall for both sides as solid and deduction for openings are made. External and internal plastering for building are taken out separately, under different times. Pointing of walls is calculated in square meter for whole surface and deductions are made similar to plastering. 11. Doors and Windows: It consists of frame and shutter. Doors and windows framers are calculated in cubic meter. Quantity is obtained by calculating length including jamb, head and sill and multiplied by cross-section of frame. Doors and window shutters are calculated in square meter. Shutter of different types should be taken separately because the rates differ. Hold-fast are taken as a separate item. 26

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12. Painting and Varnishing: Painting and varnishing of doors and windows are calculated in square meter. The area measured for this purpose is flat. 13. White washing or distempering: The quantities are taken in square meter. The inside is white wash or distemper and this item is same as internal plaster. Outside is colour wash and its quantity is same external plaster. These items need not be calculated separately and simply written as same for internal and external plaster. 14. Electrification: Generally 8% of estimated cost of building works is taken for this item. 15. Sanitary and water supply works: Generally 8% of estimated cost of building works is taken for this item. 2.2.2 I.S. Method of Taking out Quantities (Introduction only) This method includes following process: 1. Taking off;

2. Grouping;

3. Billing.

In taking off and grouping details of various items along with their quantities are calculated and entered in measurement sheet in their sequential order of execution. The process of building is done on the abstract sheet in the same sequence of items as appeared in measurement sheet. This method is easy and requires less time. 2.2.3 Squaring Squaring is the process while preparing the detailed estimate of a work in which the quantities calculated as per drawing and specification are rounding off the numerical values as per the guide lines IS 1200. After the quantities are taken out, squaring is done. It means the calculation of number, length, area volumes are in last two columns of standard measurement sheet. There are various methods of squaring. The dimensions (i) Decimal system (ii) Duo-decimal system (iii) Fractional part and practice.

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Now a day decimal system is used in which quantities are rounded off to next complete number. Squared dimensions must be checked by different person by tick mark in other colour ink, and if an correction is found, it should be cross checked. 2.2.4 Abstracting This is the last step of preparation of detailed estimate. The cost of an item is calculated from the quantities entered in measurement sheet and rates. There costs, along with rates, are entered in Abstract sheet. This process is known as abstracting while abstracting 3 to 5% amount of total cost is added for contingencies such as expenditure. While abstracting, 2% of the total cost in the estimate for the provision of work charged establishment. While abstracting 8 to 10% of total cost is added for plumbing, sanitary and electrical installation in case of estimate of a building. Following rules are following while abstracting the quantities: (i) Description of item shall be written in short. (ii) Item number shall be same as appeared in measurement sheet. (iii) Rates of items shall be written in rupees with per unit etc. (iv) Total amount of each page should be carried forward. SOLVED EXAMPLES Ex. 1: Fig 2.1 represents plan and section of a trench which is 90 cm wide and 100 cm deep. Calculate the quantity of earth work in excavation by using: 1. Long wall and short wall method 2. Centre line method.

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Solution: 1. Long wall and short wall method: Let us assume that 4.5 m side in plan is long wall and 3.5 m wide is short wall. Length of long wall for an item = Centre line length of long wall + width of item = ((4.5-0.45

+0.9

= 4.5m Length of short wall for an item = Centre line length of short wall – Width of item = (3.5 (3.5-0.45

2) – 0.9m

= 1.7m Details of measurements: Item No. 1.

Description of No. item Earth work in 1 excavation : Long walls 2 Short walls 2

L

B

H

Qty.

4.5m 1.7m

0.9 0.9

1.0 1.0

8.1m3 3.06

Total Qty.

Remark

11.16m3 2. Centre line method: Total length of centre line from the plan = [(4.5-0.45 = 12.4m No of junctions = 0 29

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∴ Deduction from length = 0 Item No. 1.

Description item Earth work excavation:

of No.

L

B

H

Qty.

in 1

12.4

0.9

1

11.16

Total Qty. 11.16m3

Remark

Ex.2: Fig. 2.2 shows the plan of a single room building with section of foundation wall. Estimal the quantities of (1) Earth work in excavation in foundation, (2) Lime concrete bed in foundation and (3) U.C.R. masonry in foundation and plinth by using long wall and short wall method any byy using centre line method.

Solution: 1. Long wall and short wall method: Let us assume 5.0 m side is long wall and 4 m side is short wall. No. of long walls= 2, No. of short walls =2 Length of long walls for an item = Centre line length of long wa wall+ ll+ Width of item Length of short walls for an item = Centre line length of short wall + width of item

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2. Central line method: Total length of centre line = [(5+0.15 = 19.2m Number of junctions with crosss walls = 0 Deduction from length = 0

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Details of measurements: Item No. 1. 2. 3.

Description of item Earth work in excavation foundation Lime concrete in foundation U.C.R. in foundation and plinth Step 1 Step 2 Step 3

No.

L

B

H

Qty,

Total Qty.

1 1

19.2 19.2

0.9 0.9

1.3 0.2

22.464 3.456

22.464m3 3.456m3

1 1 1

19.2 19.2 19.2

0.6 0.5 0.4

0.3 0.8 0.6

3.456 7.68 4.608 15.744m3

Ex: Calculate alculate the quantities of the following items in case of a underground water tank as shown in the drawing given: 1. Earth work in excavation. 2. Cement concrete (1:2:4) in foundation. 3. 1st class brick work in cement mortar (1:3) 4. 2.5 cm thick artificial stone flooring flooring. 5 16 mm thick cement plaster (1:3) on floor and walls. 6. 12 mm thick cement plaster aster (1:3) on top of wall and external plastering.

Solution: 1. Centre line method:

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Total length of centre line for 40 cm thick wall = (5.4 +3.9) = 18.6m Total length of centre line for 30 cm thick wall = (5.3+3.8)

2

= 18.2m Total length of centre line for 20 cm thick wall = (5.2+3.7) = 17.8m Details of measurement:

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Ex. 4: Fig 2.4 shows the plan and cross section of wall of a building with two rooms. Prepare an estimate with the quantities of the following items: 1. Earth work in excavation in foundation. 2. P.C.C. bed in foundation ((1:2:4). 3. U.C.R. Masonry for foundation and plinth. 4. 2.5 cm cement concrete D.P.C. 5. Brick work in super structure in C.M. (1:6), 6.. Plinth filling materials.

Total length of centre lines on the plan = 4.4

= 33.8m

Number of junctions = 2 Deduction from length = Details of measurement:

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2.3 PREPARING CHECK LIST 1. It should be checked that all the items required for execution of a work are included in the estimate. 2. All the items must be described with general specifications to guide while entering the rates in abstracting. 3. Length of various items suitable method.

should be calculated carefully by observing the drawings by

4. Rules of Tead and lift deduction additions, multiplying factors should be followed according to I.S. 1200. 5. Total quantity of an item must be expressed with its unit of measurement. 6. While abstracting item number and total quantity of items they should be taken from measurement sheet and after preparing the estimate it should be cross checked. 7. Rates of various items should be taken from D.S.R. (District schedule of Rates). 8. Total amount in abstract sheet should be calculated on every page at the bottom and carried forward on the top of next page. 9. According to the nature of work provision of contingencies as 5% of estimated cost, provision work charge establishment as 2% of estimated cost, provision of electrification (if required) as 8% of estimated cost and provision of water supply and sanitary works as 8% of estimated cost should be added the total at the end of abstracts. 2.3.1 Sequence of Execution It is an art of breaking up the work into various items of work and arranging them in the order of their execution. While sequence of execution of items of work, knowledge of that particular work whose estimate is to be prepared, shall be used. The sequence of taking out the quantities of items is same as the sequence of execution. For example sequence of items to be executed for a building is clearing the site, excavation, P.C.C. U.C.R. in foundation and plinth or R.C.C. footing, beams, columns, slabs, brick work in super structure pluming, electrification (concealed), plastering, painting etc.

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2.3.2 Brief Specification of items General Specifications of a First class Building: Foundation and plinth: Foundation and plinth shall be of first class brickwork in lime mortar (or cement mortar) over lime concrete (or 1:4:8 cement concrete). Damp proof course: D.P.C. shall be of 2 cm thick cement mortar 1:2or 2.5 cm thick cement 







concrete 1: :3, with 3 % composeal or 5% pudlo, by weight or other standard water proofing materials as specified. Superstructure: Superstructure shall be of first class brickwork with lime mortar or 1:6 cement mortar Roofing: Roof shall be RCC slab with an insulation layer and lime concrete terracing above, supporte over R.S. joists or R.C.C. beams as required. Height of the rooms shall not be less than 4 m (12’). Flooring: Drawing room and dining room floors shall be of mosaic. Bathroom and W.C. floors and dado shall be of mosaic. Floors of bedrooms shall be coloured and polished of 2.5 cm cement concrete over 7.5 cm lime concrete. Floors of others shall be of 2.5 cm cement concrete over 7.5 cm line concrete, polished. Finishing: Inside and outside shall be of 13 mm cement plastered 1:6, Drawing, dining and bedrooms, inside shall be distempered and others, inside white washed 3 coats. Outside shall be color washed two coats over one coat of white wash. Doors and windows: Frames shall be of well seasoned teak wood. Shutters shall be teak wood 4.5 cm thick paneled, glazed or partly paneled and partly giazed as required with additional wire gauge shutters. All fittings shall be of brass. Doors and windows shall be varnished or painted with high class enamel paint. Windows shall be provided with iron gratings. Miscellaneous: Rainwater pipe of cast iron or of asbestos cement shall be provided and finished painted. Building shall be provided with first class sanitary and water fittings and electrical installations. 1m to 1.5 wide apron shall be provide all round the building. General Specifications of a second class Building: Foundation and Plinth: Foundation and plinth shall be of first class brickwork with lime mortar over lime concrete.

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Damp proof course: DPC shall be or 2 cm thick cement mortar 1:2 with 3 % composeal of 5% 

pudlo by weight of cement or other standard water proofing materials. Superstructure: The superstructure shall be of second class brickwork in mud mortar except usual trimming as joints sills, etc. which shall be of second class brickwork in lime mortar. Roofing: Roof shall be flat terraced roof supported over wooden battens and beams of jack arch roof, or R.B. roof. Verandah roof may be of A.C. sheet or Allahabad tiles. Flooring: Floors shall be of 2.5 cm cement mortar plastered and outside cement mortar plaster with painting. Ceiling shall be plastered in C:M 1:3. Inside shall be while washed in 3 coats. Outside should be colour washed in 2 coats over our coat of white wash. Doors and windows: Frames shall be of well seasoned teakwood and shutters of sal, deodar or shisham wood 4 cm thick, paneled or glazed as required. They should be fitted with iron fittings and painted in 2 coats. Miscellaneous: Rain water pipes shall be of cast iron. Electrification, sanitary and water fitting can be provided as per the requirements. Detailed Specifications of Various Items of Work: (A) P.C.C. 1:4:8 for Foundation Concrete: 1. General: Ordinary Portland cement shall be used. The cement shall conform to I.S. 2691958. Cement remaining in store for more than 60 days from the date of receipt from the factory shall be subjected to tests and used only if found satisfactory. 2. Coarse aggregate Shall be of hard broken stone of granite or similar stone, free from dust and other organic materials. The stone ballast shall be of 40 mm size and well graded, so that the voids do not exceed 42 per cent. 3. Fine aggregate shall be of coarse sand, consisting of hard, sharp and angular grains and shall pass through screen of 4.75mm square mesh. Sand shall be of standard specifications, clean and free from dust dirt and organic matters. 4. Water shall be clean, from alkaline and acid matters and only potable water shall be used. 5. Proportion: The proportion of concrete shall be 1:4:8, as cement: sand: ballast, by volume unless otherwise specified. Stone aggregate and sand shall be measured by box. One bag of cement should be considered 1/30 cu. m. Size of measured box may be 30 cm
30
38  35
28 equivalen to content of one bag of cement. All materials shall be dry. If damp sand is used, compensation

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shall be made by adding additional sand to the extent required for the bulking of damp sand. Mixing shall be of machine mixing. For small work, hand mixing by batched may be allowed. 6. (a) Machine mixing: Measured quantity of dry coarse aggregate shall be first placed in the hopper. This shall be followed with measured quantity of fine aggregate and then cement. The dry materials should be mixed for at least four turns of the drum, after which correct quantity of water is added gradually while the drum is in motion. The materials shall be mixed for a period of not less than 2 minutes and until a uniform colour and consistency are obtained, the time shall be counted from the moment all the materials have been put into the drum. (b) Hand mixing: Mixing shall be carried out on smooth watertight platform of suitable size. The platform shall be so arranged that mixing water shall not flow out. Cement and sand shall be through mixed to give a uniform colour of cement and sand. Coarse aggregate shall then be added. Mix shall be turned three times in dry condition and three times after adding water. 7. Laying and compacting: Bed of foundation trench shall be light sprinkled with water before the concrete is laid. Concrete should be laid slowly and gently in layers not more than 20 cm and thorough consolidated to 15 cm with 6 kg of iron rammers. During consolidation, should be checked by water test, by digging hole of about 7.5 cm dia and 7.5 cm deep in concrete and filling with water. The water level should not more than 1.25 cm in 15 minutes if concrete has been well consolidated. When a joint in a layer of concrete are unavoidable, the end shall be sloped at an angle of 300. In laying upper layer of concrete, the lower surface shall be made rough and cleaned and watered before upper layer laid. 8. Curing: Concrete after completion shall be kept wet for a period of at least 7 days. No masonry shall be constructed upon it during this period. The curing shall be done by spreading wet gunny bags or by sprinkling water at regular intervals. 9. Measurements: Measurements shall be taken in Cu. m. for the finished concrete. The length and breadth shall be measured correct to a 1 cm and depth correct to 0.5 cm. (B) Partly paneled and partly Glazed window shutters: 1. Timber: Timber to be used shall be Indian wood; well seasoned uniform in colour, free from sapwood, knots, shakes, warp and twist, bends or detects of any king. The maximum permissible moisture content for timber shall be 12 per cent. The timber shall be planed; smooth and accurate to the full dimensions, rebate, rounding’s. An ouldings as shown in detailed drawings. Any patching or plugging shall not be permitted unless edified.

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2. Paneling: The panels shall be framed into grooves to the full depth of the groove leaving and air of 1.5 1.5 mm and the faces shall be clearly fitted to the sides of the groove. Moldings to the edges of openings shall be fixed as specified. 3. Joinery work: Joinery work shall be started immediately after the commencement of the building. All pieces shall be accurately cut and planed, smooth to the full dimensions without any patching or urging of any kind. The thickness of the styles and rails shall be specified for the shutters. The joinery shall be assembled and passed by the engineer- in charge and then the joints shall be pressed such bars all have mitered joints with the styles. The styles and rails shall have 12 mm groove in paneled portion the panes to fit in. 4. Glazing: The sizes of the openings for glazing shall be as detailed on the drawings. Unless otherwise specified; 7.5kg/m2 glass, plain or obscured and conforming to the specifications. The putty to use for fixing the glass in frames shall conform to the specifications. The glass panes shall be properly cut to fix in the rebate of the frames. Before glazing, the shutters shall be given primary coat. The rebate shall be puttied first, and the glass panes then be pressed into position. After a week the putty shall be painted along with the shutter. 5. Fixtures and fastenings: Details of fittings to be provided shall be as per the schedule of fittings supplied by the engineer-in charge in each case. The cost of providing and fixing shall include the cost of Inges and necessary screws for fixing the same. All other fittings shall be enumerated and paid for department free of cost, screws for fixing the fittings shall be provided by the contractors and nothing extra shall be paid for the same. 6. Wooden cleats and blocks Shall be fixed to windows as directed by the engineer-in charge. The size shape of cleats and blocks shall be got approved. 7. Measurements: The length and width of the shutters shall be measured to the nearest cm in closed position covering the rebates of the frame but excluding the gap between the shutters and the frame. Overlap two shutters shall not be measured. The limit of measurement shall be square metre. (c) A.C. Sheet Roofing: 1. A.C. sheets: The sheets shall be of the best quality and of approved manufactures. The sheets shall be free from cracks, chipped edges or comers and other damages. 2. Slope: The roof shall not be pitched at a flatter slope than 1:5; normally 1:3 slope is provided. 3. Purlins: The sheets shall be laid on the purloins and other roof members as per the detailed drawings and directions. The maximum spacing of purloins under the sheets shall be 1.6 m in case of 6 mm thick sheets and 1.4 m in case of 7 mm thick sheets. The upper surfaces of the purl ins shall be in one plane so that the sheets shall rest on the purlins without forcing down. 40

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4. Laying: The sheets shall be laid with smooth side upwards, with minimum side-lap of half a corrugation (4.5cm) and a minimum end lap of 15 cm. The side laps shall be laid on the side, opposite the prevailing monsoon wind. The free overhang portion shall not exceed 40 cm. In case of semi-corrugated or Trafford sheet roofing, the side overlap shall be one corrugation of 9 cms. 5. Fixing: Sheets shall be secured to the purlins and other roof members by means of 8 mm diameter G.I.’J’ or ‘L’ hook bolts and nuts. The grip of the J or L hook bolt on the side of the purlin shall not less than 25 mm. Bitumen washers and G.I. washer will be used with each hook bolt. On each purlin, the shall be one hook bolt on the crown adjacent to the side lap on either side. Holes for hooks and bolts etc. shall be drilled and not punched in the edges of the corrugations in exact position to suit the purlin while the sheets are on the roof in their correct position. The diameter holes shall be 2 mm more than the diameter of hooks. No hole shall be nearer than 40 mm to any edge of sheet. 6. Wind ties: Wind ties shall be of 40 mm
6 and shall be fixed at the eaves ends of the sheet. The fixing shall be done with the same hook bolts which secure the sheets to the purlins. 7. Measurements: The measurement shall be taken of the laid finished flat surface in sq. metre not girthed. The laps at the ends and side shall not be measured. The ridges and hips shall be measured running meter for the finished work along the centre line of the ridge or hip. Wind ties should be measured under separate item. (D) Cement plaster 1:6 proportion for a Brick Wall: 1. Cement: As per description given for P.C.C. 2. Sand: As per description given for P.C.C. 3. Water: As per description given for P.C.C. 4. Proportion: Cement and sand shall be mixed in the proportion of one part of cement to six of sand. 5. Mixing: As per desorption given for P.C.C. with different that coarse aggregate shall not added. 6. Scaffolding: Scaffolding shall be single, sufficiently strong to be safe for all construction operations and must be approved by the engineer. 7. Preliminary work: In case of old work, all joints shall be raked out to a depth equal to their widely smooth surfaces, if any, shall be roughened. All dirt, paint, etc. shall be removed. The surface prepared shall be kept wet for at least 6 hours prior to plastering. 41

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8. Plastering: The thickness of plastering shall be as specified (12mm) applied in two or three . The mortar shall be firmly applied on the surface from top downwards and well pressed into the joints. Mortar shall then be rubbed and leveled with a flat wooden rule until a perfectly plane and even surface achieved. The work shall be tested frequently with a straight edge and plumb bob. 9. Finish: While the plastered surface is fresh, a thick coat of cement slurry shall be applied rubbed smooth. 10. Curing: Curing shall be started as soon as the plaster has hardened sufficiently, not to be damage when watered. The plaster shall be kept wet for at least 10 days. Any defective plaster shall be cut rectangular shape and replaced. 11. Measurements Shall be taken in accordance with standard Mode of Measurements. (E) Uncoursed Rubble Masonry for Foundation: (U.C.R) Materials required: (1) stones, (2) cement,(3) sand and (4) water. Specifications of Materials: 1. Rubbles or stones: The stones shall be hard, sound and durable from approved quarry. The stones shall be hammer dressed and not less than 15 cm (6”) in size. The stones shall be of uniform texture, colour and preferably angular in shape. Stones with round surface shall not be used for the work. The stone quarry should be got approved by the engineer-in charge. 2. Cement: Cement shall be fresh (not stored for more than 30 days), ordinary Portland cement conforming to IS 269-1958. It shall be uniform in colour and free lumps and organic matter, gritty matter, etc. If doubtful, cement should be checked and subjected to tests and used only if found satisfactory. 3. Sand: Sand shall be well graded and sized, consisting of hard, sharp and angular grains and shall through screen of 4.75 mm Square mesh. It shall be of standard specifications, cleam and free from retested and accordingly w/c ration shall be changed. 4. Water: Water fit for drinking purpose shall be used for construction purpose. Preliminary work before construction: The foundation trench shall be properly cleaned and foreign matter, if any, shall be removed from the rench. The trench bed shall be sprinkled over with water. All the stones shall be thoroughly wetted before laying.

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Procedure of Execution: The procedure of execution of work shall be strictly carried out in the following sequence. Viz, mortar mixing laying the courses, curing and protection from foreign matter. 1. Mortar mixing: Materials for mortar shall be measured to have the required proportion of 1:6 with measuring box and first mixed dry to have a uniform colour on a clean masonry platform (water tight) and hen mixed by adding clean water slowly and gradually to have workable consistency and mixed thoroughly turning at least three times. Fresh mixed mortar shall be used, ole and state mortar shall not be used and mortar for one hour work only shall be mixed with water so that the mortar may be used before the setting of cement. 2. Laying the courses: Stones shall be well bonded and properly laid over the mortar bed laid in the French at the start of work. The stones shall be laid with the broad face downward to give good bedding. The joints should not be thicker than 10mm. The stones shall be properly dressed to secure close joints and unterices etc. should be suitably filled up with stone spalls and chips embedded in cement mortar wherever necessary. Though bond stones of one piece shall be provided at 1.5 m c/c of face and should extend for full thickness of wall. For thicker walls two placed side by side with minimum overlap of 15 cm 

should be provided as bond stones. Breadth of bond stones shall not be less than 1 times height of stone. Not more than 60 cm height of masonry shall be constructed at a time. Every face of wall should be ruly vertical and truly in plumb. All the joints should be raked (for plinth portion) and face of walls cleaned the end of days work or before starting next day work. 3. Curing and protection: At the end of days work the top of masonry shall be flooded with 2.5 water at surface. Masonry should be kept wet for a period of 10 days and the masonry should be made by sprinkling water at regular interval of 1to 2 hours. Measurements and Rates: Measurements required: (1) Bricks (2) Cement, (3) Sand and (4) water. Specifications of Materials: 1. Bricks: All the bricks shall be of Standard Specifications and of required class and made of brick earth thoroughly burnt in clamp. Brick shall be uniform in colour and texture, regular in shape size and their edges should be sharp and square and shall give a clear ringing sound on being struck and be free from cracks, chips, flaws and lumps of any kind. The brick should not break if it is dropped from height of 1 M. Bricks shall not absorb more than 15% of water by its weight after one hour of soak when immersing in water. Brick shall have a minimum crushing strength of 105 kg/m2. 43

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2. Cement: Cement shall be fresh (not stored for more than 30 days). Ordinary Portland cement confirming to I.S. 269-1958. It shall be uniform in colour and free lumps, gritty matter etc doubtful, cement should be checked and subjected to tests and used only if found satisfactory. 3. Water: Water fit for drinking purpose should be used for construction purpose. 4. Sand: Sand shall be medium graded and sized, consisting of hard, sharp and angular grains shall pass through screen of 4.75 mm square mesh. It shall be of Standard Specifications, Clean and from dust, dirt and organic matter. It shall preferably be dry or else the moisture content may be detected water cement ration shall be changed accordingly. Preliminary work Before Construction: Bricks shall be fully soaked in clean water by immersing in a tank for a period of 12 hours immedia before use. Soaking shall be continued till air bubbling is ceased. The surface of already constructed U.C.R. masonry up to plinth level shall be watered before starting work of laying bricks. The surface shall be properly raked and cement slurry should be poured, if masonry is to be constructed in continuation with old structure. Procedure of Execution: The procedure of execution shall be strictly carried out as follows: 1. Mortar mixing: Materials for mortar shall be measured to have the required proportion of 1:5 measuring box and first mixed dry to have a uniform colour on a clean watertight masonry platform then mixed by adding clear water slowly and gradually to have workable consistency and mixed thorough by turning at least three times. Fresh mixed mortar shall be used, ole and stale mortar shall not be used mortar for one hour work only shall be mixed with water, so that the mortar may be used before the of cement. 2. Laying the courses: Bricks shall be well bonded and laid in English Bond unless otherwise specified. Every course shall be truly horizontal and wall shall be truly in plumb. Vertical joints consecutive course shall not come directly over one another. Vertical joints in alternate course shall come and shall be placed near the ends of the wall. Selected best shaped bricks shall be used for face work. Mortar joints shall not exceed 6 mm in thickness and joints shall be fully filled with mortar. Bricks shall be laid with Frog upward except at topmost course where frogs shall be placed downward. Brick work shall be carried out not more than 1 m height at a time. When one part of wall has to be delayed, Stepping shall be left at an angle of 450. Corbelling or 

projections where mode should not be more than ! bricks projections in the one course. All joints shall be raked and faces of wall cleaned at the end of each day’s work. 3. Curing and protection: At the end of day’s work the tops of walls shall be flooded with water by making small weak mortar edging to contain at least 2.5 cm. Deep water. The brick 44

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work shall be kept wet for a period of at least 10 days after lying. The brick work shall be protected from the effect of sun, rain, frost etc. during the construction of, and until such time it is green and likely to be damaged. 4. Scaffolding: Necessary and suitable single scaffolding shall be provided to facilitate the construction of brick wall. Scaffolding shall be sound and strong and support members sufficiently strong so as to withstand all loads’ likely to come upon them. It should be got approved by the engineer-in charge before using. 5. Measurements and rates: Brick work shall be measured in cu.m. and measurements of length, breadth and height shall be taken to nearest 1 cm to compute the quantity. The thickness of wall shall be taken as multiple of Half Bricks. The measurements should be as per I.S. 1200. (G) Specification for Form Work for R.C.C. Works: 1. Form work: The form work shall be of timber, plywood or steel plates as approved by the engineer-in charge. The timber used should be strong enough to avoid undue deflation when loaded and not liable to warp. It shall be of rigid construction according to the shape and dimensions shown on drawing. It should withstand the dead load, live load and other forces causes due to ramming and vibrations of concrete. Number of braces and ties should be used to give additional strength. The form work shall be constructed in such a manner that it can be easily removed without damaging the surface. The form work should be got approved by the enginner-incharge before reinforcement bars are placed in position. 2. Props and centering: Props used for centering shall be of steel, timber and bellies shall be of 100 mm. The bellies shall rest over the sole plate provided with double wedges. Before placing the concrete the props and wedges shall be thoroughly checked. During concreting a watch should be kept on props. 3. Shuttering: The timber plates or steel shall be used. The wooden boards should be smooth and even surface. The joints shall be packed so as to stop leakage during concreting. The openings for fan hooks etc. Shall be provided in shuttering as directed by engineer-in charge. Before concreting, the surface of wooden plate or steel plate should be treated with raw linseed oil burnt oil so that the concrete will not adhere to form work. The necessary slope shall be provided as per drawings. 4. Removal of form work: After slab and beam construction, the sides of beam shall be stripped first. Then the underside of slab and lastly underside of beam. The period of removal of form work different items is as follows: 45

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Item 1. Sides of columns, beam and wall 2. Undersides of slabs 3. Undersides of beams and arches

Period of removal 48 hours or 2 days 7 to 14 days 14 to 21 days

5. Measurement: The unit of measurement is M2 (H) Marble Mosaic Tile Flooring: Material required : (1) Mosaic tiles, Surkhi.

(2) Cement, (3) Sand, (4) Lime, (5) Water (6)

Specification of Materials: 1. Mosaic tiles: The marble mosaic tiles should confirm to I.S. 237-1959 and the sizes should be given in the following table. Sr. No.

Nominal Length (cm)

Actual length (cm)

Nominal Length (cm)

Actual breath (cm)

1. 2. 3.

20 25 30

19.85 24.85 29.85

20 25 30

19.85 24.85 29.85

Thickness (mm) 20 22 25

The tiles should be of required nominal size and manufactured under press-machine under a pressure 140kg/cm2. The tiles should be supplied after being grinded on machine. Other specifications are (for sand, cement, etc) as already discussed for Brick and U.C.R. masonry. Preliminary work before construction: The sub grade concrete or R.C.C. slab on which tiles are to be laid shall be cleaned roughened wetted before laying the bedding for tiles. The tiles should be cleaned and washed before lying. Procedure of Execution: The procedure of execution shall be strictly as discussed below. (1) Lime mortar mixing: The bedding ingredients shall be taken in proper proportion. 1:1:2 Lime putty surkhi and coarse sand. 46

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1:3 Lime putty and surkhi, 1:3 Lime putty and coarse sand, And shall be thoroughly mixed in dry form to obtain uniform colour and shall be taken to ensure that there are no hard lumps present, water shall then be added and the ingredients shall be thoroughly mixed. Freshly prepared bedding mortar shall be used. (2) Laying the bedding and mosaic tiles: The lime mortar beading shall speeded rammed and corrected to proper leaves and allowed to be hardened sufficiently for one day. The tiles should be laid over a thin layer of cement paste (of honey like consistency) of about 1.5mm thickness spread over the lime mortar bedding, with a vertical joints of 1 to 1.5 mm thickness which spread over the lime mortar bedding, with a vertical 20 mm as per I.S. 1443. The tiles shall be laid one another, each tiles being gently tapped with a wooden mallet. Tiles are properly bedded and in proper line and level which shall be checked by straight edge, as least 2 m long, and level bottle. The required slope shall be properly provided. If it is not possible to lay full size tiles due to less space, the same shall be cut off to required size to suit the space and rubbed and made smooth so as to form thin joint. The joints with wall shall be neatly finished and mad to correct shape. (3) Curing, polishing and finishing: After laying the tiles, the day after, all the joints shall be cleaned off the grey cement grout with a wire brush to a depth of 5 mm and all the dust and loose mortar shall be removed and cleaned. Joints are grouted with the white cement mixed with or without pigment to match wearing layer of the tiles. The same cement slurry shall be applied on the surface over the entire room in a thin coat protecting the tiles from abrasive damage and fill all the holes that may exist on the surface. The floor shall then be kept wet for at least 7 days and there after grounded evenly with machine fitted with Coarse Grade Grit Block’s No. 60 with water being used for thorough washing in order to fill any hole that appears. The surface shall then be cured and then grinded with machine fitted with Fine Stone No. 120. In the small areas or where circumstances so required, hand polishing shall be done using Stone Grade – 60. Procedure of Execution: For first rubbing, Medium stone Grade No. 80 For medium rubbing and Stone of Fine Grade No. 120 for final rubbing shall be used in the same manner as described in machine grinding. Oxalic acid shall be dusted over the surface at a rate 33 gm/m2, sprinkled with water and rubbed hard with a pad of woolen rags. The following day the floor shall be wiped with a moist rag and dried with a soft cloth and finished clean. 47

Dhanvantari College of Engineering

Damaged tiles or distorted tiles if any shall be properly replaced, jointed and polished. The floor shall not sound hollow when tapped with wooden mallet. Measurements and Rates: The quantity shall be measured in sq.m. and depth. Breath shall be measured to the nearest before laying skirting or dado or wall plaster. No deduction shall be made, nor extra paid for any opening in the floor for area upto 0.1m2. Treads of stairs and steps paved with tiles without nosing shall be measured under flooring and moulded nosing shall be paid on running meter. The width of tread shall not be greater than 30 cm. Rate shall include cost of all the materials, machines and labour involved in the process of laying the tiles. (I) Fixing of Hume pipes: Materials required: (1) R.C.C. Hume pipes, (2) Cement, (3) Sand, (4) Water and (5) Spun yarn Hemp. Specifications of Materials: The pipes used for the culvert should be strictly as per standard specifications and manufactured on workshop. The surfaces should be smooth and ends should be neat in shape. The specifications for the other materials like cement, sand and spun yarn are same as already discussed in the previous specifications. Broken pipes should not be used. The pipes should be properly checked before being used. Preliminary work before Construction: The bed should be cleaned properly and foreign matter should be removed. Wherever joint are likely come extra excavation should be done to provide sufficient working space round the joint. The pipes should be washed with water particularly at the two ends. Procedure of Execution: The procedure of execution shall be as follows: 1. Mixing of mortar for joints: This shall be strictly carried out as already discussed in previous article and should be done after the laying of pipes is over. 2. Laying: The pipes shall be properly laid after checking the bed at required slope. After laying the pipes, joints shall be filled with fresh cement mortar to a neat finish. Use of old or stale mortar shall be avoided. The pipes shall be embedded in cement concrete for protection. 48

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3. Curing and protection: The joints shall be cured for 10 days with water or wet gunny bags necessary depending upon situation. Protection cover of concrete should be provided around the pipe as detailed drawings. The pipes shall be tested for leakage. Leaky joints if any shall be rectified and broken pipe if any shall be replaced and joints finished to the satisfaction of engineer in charge. Measurements and Rates: The measurements are taken in running meter for a given diameter of pipe. No extra provision is mad for excavation around the joints. Rates include all the materials, labour etc. used for the construction purpose. 2.3.3 Contents of Measurement Sheet Name of work

Item No.

Description of No. particulars of item

Length

Breadth

Height or Quantity Depth

2.3.4 Abstract Sheet

Item No.

Description or particulars of item

Quantity

Unit

Rate

Amount

2.3.5 Face Sheet This sheet is attached at the cover page of a detailed estimate prepared, to mention, details of the project for which the estimate is prepared. It shall include the following: (1) Name of the proposal. (2) Introduction to the organization. (3) Statement of total cost of the project. 49

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(4) Objective of the project or work. (5) Methods of estimates followed. (6) Numbers of I.S. codes used while preparing detailed estimate. (7) Project evolution which includes agency and authority. (8) Time required for completion of project or work. (9) Funds required for project and foundation agency. 3.1 GENERAL Measurement of civil engineering works occupies a very important place in planning and execution of works, right from the stage of preparation of estimate to the final completion of works and settlement of payment of the works to the contractors. There are some differences regarding the method of measurement among the state Government departments. But the method introduced by the Indian standard (I.S.) is legal and basic document for removing ambiguities and setting all the disputes for making payment to the contractors. 3.1.1 Rules for Fixing Units of Measurement of Items of Works 1. Each item shall be fully described. 2. The measurement shall be taken in the order of sequence of length, breadth or width and height or depth. 3. Dimensions shall be measured to the nearest to 0.01m, 4. Area shall be worked out to the nearest to 0.01m2. 5. Cubic contents shall be worked out to the nearest to 0.01m3. 6. The same work done under different conditions shall be measurement shall be measured separately stating separately staring the conditions, the lift and lead wherever possible. 3.2 MODES OF MEASUREMENT OF ITEM OF WORKS AS PER PWD HAND BOOK AND I.S. 1200 AND DESIRED ACCURACY IN TAKING MEASUREMENTS 3.2.1 Earth Work Earth work is measured and paid at per % cubic metre but in case of difficult works, it is paid per cubic metre such as hard rock by blasting or chiseling. The length, breadth and height shall be measured to get the cubic content. 50

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Earth work for different nature such as excavation in foundation trenches, excavation in cutting and filling shall be measured under separate items. Unless otherwise specified the materials to be excavated shall be classified as soft soil, hard soil, soft rock and hard rock etc. when the ground is uneven, levels shall be taken before the start and after the completion and average depth of excavation of filling is worked out from these levels. No separate measurements are taken for setting out works, profiles, site clearance; bailing out water from rains etc.as these are included in the rate. Lead and lift: The normal lead is 30 m and lift is of 1.5 m. Separate measurements are taken for every 30 m lead and every 1.5 m lift or depth. For additional lead of every 30 m and lift of 1.5 m the rates shall be different. Foundation trench: Foundation trench shall be measured in cu.m. for rectangular section. Length of trench, bottom width and the depth shall be measured as vertical depth. Return, fill and ram: Returning, filling and ramming of excavated earth shall be taken in cu.m. Under separate item and shall include spreading in layers not exceeding 20 cm in depth, watering, ramming and leveling. Pudding: Clay puddle work shall be taken in cu.m. and shall be described including supply of clay, preparation, placing in layers of 15 cm thick of ramming etc. Surface excavation: Excavation exceeding 1.5 m width as well as 10.0 sq.m in plan but not exceeding 30 cm in depth shall be considered as surfaces excavation. Timbering: The planking and strutting required upholding the face of excavated earth shall be classified under separate item and measured in sq.m. Whenever it is not possible to make measurements from cutting and filling shall be measured and deduction for shrinkage of voids shall be made from actual measurements. Generally, 10% deduction shall be made in case of ordinary consolidated fills and in case of consolidation done by machinery; a deduction 5% shall be made. 3.2.2 Concrete For concrete, complete description of size of aggregate, grading, proportion and method of mixing etc. shall be given. Different kinds of concrete such as lime concrete, cement concrete, R.C.C. of different proportion of different materials shall be classified and measured under separate items. The length, breadth and height or thickness shall be measured to the nearest 1 cm but the thickness of slabs, post, beams shall be measured to the nearest 0.5cm.

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Unless otherwise specifically mentioned, form work shall be measured separately in sq.m. under separate item. Form work shall be measured to the nearest 0.5 cm. No separate measurements for fair finishing of exposed surfaces of concrete shall be taken but these shall be included in item. Special finished shall be measured separately. R.C.C. work: Reinforced cement concrete is measured separately from unreinforced cement concrete. R.C.C. work excluding steel shall be measured in cu.m. and reinforcement measured under separate item in quintals. Form work is not measured separately. The volume of reinforcement shall not be deducted from volume of concrete. Light weight partitions shall be measured in sq.m. Complete description with thickness shall be mentioned. Expansion joints: Expansion joints shall be measured in running meter (RMt) but the depth and width of joints and materials used for filling shall be specified. Damp proof course (D.P.C.) : D.P.C. in concrete shall be described fully and measured in sq.m., mentioning its thickness. Form work, finish, leveling curing etc. Shall be included in the item. The horizontal and vertical D.P.C. shall be measured separately. 3.2.3 Brick Work A complete description of the bricks and mortars with proportion shall be given. Different classes of brick work shall be taken under the separate items. Unless specifically mentioned, all brick work shall be of English bond. The item of general brick work shall be deemed to include the following: 1. Raking out joints. 2. Leaving holes for pipes etc. 3. Bedding wall plates, lintels, sills etc. Measurement: Brick work shall be measured in cubic metres. The length, breadth or thickness and height shall be measured. The length and height shall be measured to nearest 1 cm. Thickness of wall: Brick walls of one brick thick, i.e. 20 cm and less shall be measured separately in sq.m. Stating its thickness. Deductions: No deductions shall be made for the following: 1. Opening upto 0.1 sq.m. in area. 2. Ends of beams. Lintels, posts etc. up to 0.05sq.m. in secion.

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3. Wall plates, bed plates, bearing of slabs etc. 4. Iron hold fasts. Pillars: Pillars shall be fully described and measured for their net volume. Honey combed brick work: Honey combed brick work shall be measured in sq.m. stating its thickness and pattern of honey combing. Holes or openings in honey combing shall not be deducted. Reinforced brick work: Reinforced brick work shall be taken in cu.m. and kept under separate item Reinforcement shall be measured in quintals. Brick edging: Brick edging for roads, footpaths, shall be described and measured in running (RMt). 3.2.4 Stone Masonry Complete description of stone, materials of mortar and their proportion shall be stated. Different of stone masonry such as random, course, uncaused or ashlar shall be taken under separate item. Stone masonry shall be measured in cu.m. and face work in sq.m. The deductions for stone shall be same as that of brick masonry. Dressing of stones in sills, cornices and lintels shall be measured in cu.m. the type of dressing shall be stated fully. 3.2.5 Roof Covering The roof covering shall fully describe the materials and workmanship. It is generally measured in sq.m. The flat area of roof covering shall be measured without allowance for laps corrugations. Opening upto 0.4 sq.m. Shall not be deducted. Supporting structure such as wood work and steel work shall be measure separately. Asbestos cement roofing: The type of sheeting plain, corrugated, or semi-corrugated stating thickness, method of fixing shall be described. It is measured flat not girthed. Ridges and hips shall measure separately in running metre. Roof tiling: The kind, pattern, quality and sizes of tiles, method of lying shall be described. Single and double tiles shall each be measured separately in sq.m. Rides, hips and valleys shall be measured separately in running meter. Eaves tiles bedded in mortar in walls be measured in running metre extra over for eaves describing the mortar and width of bedding. Jack arch roofing: Jack arch work including haunch filling with concrete shall be measured flat over in sq. m. The clear span, rise and thickness of arch, method of laying, jointing and pointing with mortar shall be described. 53

Dhanvantari College of Engineering

Stone slab roofing shall be measured in sq.m. Stating its thickness and quality. Lime concrete terracing shall be taken in sq.m. Under a separate item, stating the average thickness. Rain water fitting: Rain water pipe and gutters shall be described and measured in running metres. A Special required such as bends, junctions etc. and fittings shall be included in the item. The method jointing and fixing shall be described. The length shall be measured along with the central line. 3.2.6 Ceiling The materials, its thickness and method of fixing shall be fully described. It is measured in sq.m. Supporting members shall be measured separately. Openings up to 0.4sq.m. Shall not be deducted. Cover fillets over joints shall be measured separately in running metre stating the material, width and thickness. In case the edge of fillets is to be chamfered or rounded, this shall be described. Insulation boards or slabs fixed to the walls or roof shall be measured in sq.m. Stating its thickness, number of layers and method of fixing. 3.2.7 Floors and Paving –Dado and Skirting All work shall be measured in sq.m. Describing the method of bedding, jointing and surface finishing. Different types of flooring such as brick, stone, marble, mosaic etc. Shall be measured separately. Different kinds of finishes shall be measured separately according to mix, thickness, nature of finish etc. The polishing and rubbing of marble, mosaic or stone flooring are included in the item. The pointing of brick flooring shall be measured in sq.m. Separately, unless otherwise stated. Lime concrete or cement concrete bedding shall be described and measured separately in cu.m unless otherwise stated. Dado shall be measured in sq.m. Skirting shall be measured in running metre stating its height. 3.2.8 Plastering and pointing Plastering: Plastering shall be measured in sq.m. Stating thickness, proportion of mortar. Plastering on roofs, ceiling and walls etc. shall be measured under separate item. External plastering at a height greater than 10 m above ground level shall be measured separately in stages of 5 m height. Plastering bands 30 cm or below shall be measured separately in running metre. Deductions: As per I.S. 1200 are lareadydiscussed in chapter 2-2.1.3(5). Pointing: Pointing shall be measured in sq.m. and measured flat of the whole surface area. Various types of pointing shall be kept separate. Raking out joints shall be included in the item. 54

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Deduction shall be the same per the plastering item. 3.2.9 Painting Painting shall be taken in sq.m. Stating the number of coats and measurements shall be taken flat preparatory work such as cleaning, rubbing down, removing, burning etc. shall be described. Work such as stopping, knotting, shall be stated. Work on different surfaces such as plaster, concrete, steel and wood shall be measured under separate item. No deductions shall be made for opening upto 0.5 sq.m. each and no additions shall be made for painting for jambs, soffits, sills etc. of openings. Painting on gutter or rain water pipes, ventilating pipes, steel pipes and eaves gutters shall be measured in running metres stating the size or girth. Varnishing and coal tarring shall be measured in the same way as for painting. Corrugated sheet surface shall be measured flat in sq.m. and their areas are increased by the same percentage as that of white washing. The coefficient or multiplying factors for different surfaces of painting to get equivalent area given in the following tabular form. For doors and windows the multiplying factors are given in chapter 2 2.1.3. (5). Particulars 1. Corrugated iron sheeting for roof 2. A.c. corrugated sheeting in roof 3. A.C. semi-corrugated sheeting in roof 4. Steel rolling shutters 5. Boarding with cover fillets and match boarding 6. Roof battens for tile or slate roof 7. Trellis work 8. Railing, grills, expanded metals

Method of measurement Measured flat not girthed Measured flat not girthed Measured flat not girthed

Multiplying average 1.14 (for one side) 1.20(for one side) 1.10(for one side)

Measured flat not girthed Measured flat not girthed

1.25 (for one side) 1.05(for one side)

Measured flat overall, no &(for painting all-over) ! deductions for open spaces Measured flat overall, no 2 (for painting all-over) deductions for open spaces Measured flat overall, no 1 (for painting alldeductions for open spaces oaver)

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3.2.10 White Washing, Colour Washing and Distempering All work shall be measured in sq.m. All preparatory work such as cleaning, booming, scraping, etc. shall be included in the item. The item shall included repairs of surfaces not exceeding 0.1 sq.m. Different types of works shall be measured separately and described. Method of deduction is the same as described for plastering in Chapter 2-2.1.3 (5). Corrugated surface shall be measured as flat and girthed in sq.m. and the quantities so measured shall be increased by the following percentages and added with the measured area. Corrugated iron sheets – 14 per cent. Corrugated asbestos sheets- 20 per cent. Semi- corrugated or Trafford sheets – 10 per cent. 3.2.11 Sanitary and water supply works Earth work for laying pipe line and other appurtenant items shall be the same as given in the item of earth work. Pipes shall be measured in running meters, inclusive of all bends, junctions, etc. which shall to be measured separately. The measurements shall be taken along the centre of the pipes and fittings or specials. Testing of pipe line shall be included in the item. The measurements for concrete work for bedding, benching etc. shall be as given in the item, concrete work. Fittings and appliances: Gullies, siphons, fire hydrants, including concrete bedding and setting in position shall be enumerated separately after fully describing the item. Connection of fittings, elbows, bends, tees etc. shall be enumerated. Manholes: Manholes and inspection chambers up to 6 m depth shall be enumerated stating the size and depth. The item include cast iron cover with frame materials, form work etc. all of which shall be fully described. The manholes shall be classified into different groups, depending upon the depth as given below: (i) Shallow –upro 2.1m. (ii) Deep- above 2.1 m and upto 4.2m. (iii) Extra deep – above 4.2 m and upto 6.0m. Manholes exceeding 6 m depth shall be measured in detail under the various items of work such as, brick work, concrete etc. 56

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3.2.12 Road Work Materials for road work: The quality and size of materials shall be described and their sources of supply shall be stated. Measurements shall be taken in stacks prepared on level ground and measured in cu.m. Road metal of different sizes shall be measured separately. Usually road metal is stacked along the road on the side berms and the cross- sectional measurement is taken with the help of stacking template of trapezium type and the length of stacks are measured to get the quantity. Earth work excavation and earth work necessary to bring the road alignment to proper levels, shall be measured in accordance with the rules mentioned under item earth work. Rolling and watering formations shall be measured separately in sq.m. Soling: In case of soling etc. The measurements shall be done in sq.m. or cubic metres. Soling of boulders or quarried stone shall be described stating its thickness. Berms: Preparation of side berms shall be measured in running metres or km stating average filling and width. Edging: Edging shall be measured in running metres stating the materials to be used and method of placing. Necessary excavation is included in the item. 3.2.13 Tar and Bitumen Road Tar and bitumen also called as binder shall be described stating the type, grade, penetration, quantity of binder, s tone grit etc. The tar and bitumen road is generally measured in sq.m. Surface painting shall be measured in sq.m. and the quantity of binder in kg per sq.m. and the quantity of stone grit in cu.m. per sq.m. Required on road surface shall be described. Premix carpet shall be measured in sq.m. and the quantity of binder in kg per cq.m. and the quantity of binder in kg per sq.m. Shall be stated. The consolidated thickness of layer shall be stated. Cement concrete road: Cement concrete road shall be measured in cu.m. From work for the pavement not exceeding 20 cm shall be included in the item. For those exceeding 20 cm in thickness, the form work shall be measured separately. If the concrete is reinforced it shall be so stated and measured separately. Expansion joints shall describe and measured separately in running meters stating the thickness and the depth of the joint.

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3.2.14 Desired Accuracy in Taking Measurement During the measurement of dimensions of various components of civil engineering structures accurate is required to be maintained. Accurate dimensions give exact quantity of an item of work, which furth helps in calculation of quantity of material and labour. Following points shall be observed during measurement of various items of work: (1) Measurements shall be taken in the order of sequence of length breadth and height or depth. (2) Dimension shall be measured to the nearest 0.01 mt. (3) Area shall be worked out to the nearest to 0.01 sq.mt. (4) Cubic content shall be worked out to the nearest 0.01 cu.ml. PROCEDURE FOR PREPARING DETAILED ESTIMATES 4.1 GENERAL Detailed estimate is prepared to calculate the quantities of various items of work for civil engineering structures. For preparing this, drawing and specifications of items is required. In this chapter step-by-step procedure for preparing the detailed estimate is explained with the help of suitable example. 4.1.1 Procedure for Taking out Quantities for Various Items of Works by P.W.D. and IS 1200 For preparing the estimate and costing, it is necessary to determine the quantities of various items. With the help of drawings and specifications each item is taken with full description and length, width, depth is determined. Items are expressed in m3, m2, and running metre and in numbers according to the mode of measurement while preparing estimates, in taking out quantities study of drawings, visit of site, sequences of operation accuracy, deductions of openings, etc. are followed. Method of taking out quantities: There are 2 methods of taking out quantities or methods of estimating: 1. P.W.D. method,

2. Centre line method.

(public works Department) (I) Load Bearing Structure:

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1. Prepare foundation plan showing centre line with all dimensions. Centre to centre dimensions taken out by adding half width of each cross wall to inner dimensions of a room. 2. Now divide the walls in two groups. In plan, walls in horizontal direction are called long wall and vertical direction walls are short walls and vice versa. *It is advisable not be change the grouping of wall to avoid errors. 3. Measure length of long wall for an item by using formula Long wall length for an item = Length of centre line of long wall + Width of item 4. Measure length of short wall for an item by using formula. Short wall length for an item = Length of centre line of short wall-Width of item This method is adopted by state P.W.D. Advantages: 1. This method is simple and accurate. 2. There are no chances of mistake in calculation. 3. The method gives quantities quickly. Centre Line Method: 1. Prepare the foundation plan of the given drawing. Write centre line lengths of each wall in it. 2. Find the total length of the centre lines of long and short walls, having same type of footing. That corners of building where two walls meets are not taken in kuncions and if two walls meets a wall some point take n = 2 at that point. 4. For an item calculation of length is done as below: 

Length for an item = Total centre line length –n
( width of item) N= number of junctions of cross walls with main walls 5. For buildings having different types of walls, each set of walls should be taken separately. Advantages: 1. It can be used for calculation of quantities of rectangular, circular and polygonal buildings. 2. This method is simple and quick. 59

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3. Calculation are easy and less. Deductions of Openings: When area of volume of openings are to be deducted from various items like plastering pointing and brickwork for superstructure following rules should be used. 1. Measured the quantity without considering opening. 2. Deduct the openings quantity by considering bearings. No deduction is made for the following in case of brickwork in superstructure: 1. Opening each upto 0.1 sq.m. 2. Ends of beams, posts, rafters, purlins upto 0.05sq.m. in secion. 3. Wall plates, bed plate, bearing of chaiia upto 10 cm depth. 4. Bearing of floors and roof slabs etc. For opening of doors and windows and arches deductions from masonry is given below:

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Deduction = l

Rules for deductions in plastering and pointing: 1. No deduction is made for ends of beams, posts and rafters etc. 2. No deduction is made for small opening upto 0.5 sq.m. and no addition is made for jambs, soffits and sill of these openings. 3. For openings more than 0.5 sq.m. and less than 3 sq.m. Deduction is made for one face only. 4. For opening above 3 sq.m. both faces are deducted and area of jambs, soffits and sill are added. (II) For Farmed Structure Building: [A] R.C.C. works. R.C.C. works complete in one item, including concrete, steel aand form-work. 2. Whole R.C.C. work is divided in three parts: (a) Concrete works; (b) Steel works; (a) Concrete works; (b) Steel works; (c) Centering and shuttering or form form-work work and quantities of each above item are separately calculated. 62

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[B] Calculation of quantity of concrete: It is calculated by determining by volume of concrete member (slab, column, beam, etc.) and expressed in cubic meter. Note: According to I.S. 1200 no deductions are made for steel while calculating quantity of concrete. [c] Calculation of quantity of steel: Approximately the quantity of steel for a R.C.C. member can be calculated as below; when detailed drawings and designs are not available. (a) For lintel and slab: Quantity of steel = 0.7 to 1% of quantity of concrete (m3) But steel is not expressed in cubic meter, so quantity in quintals is calculated by considering the densely of mild steel. As 1 cubic mt. of steel = 78.5 quintal = 7850 kg 1 tonne= 1000kg 1 quintal = 100 kg (b) For beams: Quantity of steel = 1 to 2 % (c) For columns: Quantity of steel = 1 to 5% (d) For foundation and footing: Quantity of steel = 0.5 to 0.8% For R.C.C. work finishing no extra payment is made. Minimum cover for steel should be provided as below: For slab- side cover 4 cm to 5 cm; top and bottom cover 1.2 cm to 2 cms. For beams – 2.5 cm to 5 cm. [D] Measurement of length of reinforcement Standard hook: 63

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[E] Bar bending schedule: For guidance of supervisors and laborers it is provided. It is list of the reinforcement bars given give in tabular form as below: Sr. No.

Description

Shape bar

of Dia. Of bar No. of bars in mm

Total length of Wt. in kg abr in mtr.

It is the list of reinforcement bars in tabular form giving the particulars of bars, shape of bending with sketches, length off each bar, total length and total weight for each R.C.C. work, a schedule of bar or bar bending schedule is prepared. From this requirement of different size and length of bars may be known and bent up during the time of construction. Hooks are not provided provi in case of Tor steel. 64

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Weight of different bars: This table should be referred while calculating quantity of steel. Dia. In mm 6 8 10 12 14 16 20

Wt. in kg/mtr. 0.22 0.39 0.62 0.89 1.21 1.58 2.47

Dia. In mm

Wt. in kg/mtr.

22 25 32 36 40 50

2.98 3.85 6.31 7.99 9.86 15.41

4.2 PROVISIONS IN DETAILED ESTIAMTE The following provisions are made in the estimate other than the items of work, their quantities and cost: (1) Provision of contingencies: During the execution of works there will be some miscellaneous expenditure which cannot be classified under any subhead or any item. These are the expenses of misc. character. To meet such expenses, 3 to 5% of estimated cost is provided, which is known as contingencies. If there is a saving in the amount of contingencies, it can be used for extra items after getting the sanction from competent authority. Tools and plants (T. and P.) : For a big work or project 1 to 1.5% of estimated cost is provided in estimate for purchase of tools and machinery required for execution of works. (2) Work charged Establishment: It is the establishment whose expenditure is directly charged to the works. During the period of construction, the service of work-supervisors, store clerk, mistry, chowkidar etc. are required. These ae Temporary employees and their salary is paid from the amount of work charged establishment provided in the estiates. For this, about 2% of estimated cost is included I the estimate. The services of these staff are terminated at the expiry of sanctioned period, and for new works fresh sanction is required. The services of these staff can be terminated at any time, but usually, one month’s notice is given. (3) Provisional Quantities: When the quantities of a particular item are not certain, provisional quantities are worked out and provided separately in the estimates for such items. For this purpose quantities are calculated from measurement of the drawing with certain assumptions of the probable increase and are kept 65

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in bill of quantities. These items are marked us ‘provisional’. The payment of provisional quantities is made on the completion of these items of work, after knowing the exact nature. Example: 1. Nature of soil is uncertain, below the ground so depth of footing may vary. 2. Lengthening or shortening of concrete piles. (4) Provisional Sum: While preparing an estimate, the details of a specialized item or special work done by specialists, are not known, some amount is provided in the estimate or bill of quantities for such items. It is called provisional sum. Example: Installation of lift, air conditioners fitting, installation of refrigerating machine. During the execution of work. Quotations are called for this specialized item from firms or contractors. The contractor is not allowed to alter the amount of provisional sum and if he does will be treated as invalid. (5) Electrification, sanitary and water supply works: While preparing the estimate, a lump sum provision of 20% is made in the estimate. For water supply and sanitary

- 8% of the estimated cost.

For electrification

- 8% of estimated cost

For electric fans

- 4% of estimated cost.

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