Fundamentals of Estimating and Costing

Fundamentals of Estimating and Costing

1. Fundamentals Of Estimating and Costing

2.  Es t ima t e is requir e d to k no w the QUANTI T Y O F M A T ERIAL and CO ST OF WORK.

3.  It is defined as the process of working out the APPROXIMATE QUANTITY of a work. It is prepared by- Working out Quantities. Calculating the cost at suitable rates.

4.  It is defined as the process of determining the ACTUAL COST of the work before starting the work. Costing is done by use of- Measurement sheets Abstract Sheets.

5.  To know Approximate Cost . To know quantities of Materials & labors. For getting Technical Sanction. For inviting Tenders. To get Time of Completion.

6. To know Actual Cost . To do Financial Planning . Alterations in plans can be done if costing goes beyond the capacity.

7. Approxi m ate E s t imat e : It gives u s an Approximate amount needed for the project. Detailed Estimate: It gives us a Detailed amount which is very near to the actual amount needed for the project.

8. Service Unit Method Plinth Area Method Cubical Content Method Typical Bay Method Approximate Quantity Method

9. Revised Estimate Supplementary Estimate Revised & Supplementary Estimate Repair & Maintenance Estimate Renovation Estimate

10. It is a type of detailed estimate which is prepared if in the project work there is change in design and planning. Also when actual cost of construction increases by 5 to 10%. Even if there are material changes from original proposal, still Revised estimate is made.

11. It is a type of detailed estimate which is prepared when there is additional work in the project. E.g. If in a bedroom, attach toilet is not provided in original estimate & later it is decided to construct the toilet block, Supplementary Estimate is necessary.

12.  It is a type of detailed estimate which is prepar e d if it is combine Revised nec e ssary to Esti m ate & Supplementary Estimate.

13. It is a type of detailed estimate which is prepared whenever it is necessary to repair and maintain any structure in its working condition . Buildings- White washing, Color washing, Minor Repairs etc. Roads- Patch Work, Repairs of Bridges, culverts etc.

14.  It is a type of detailed estimate which is prepared to do the Renovation of Buildings, Bungalow, Flats etc. after some years of use.

15. It is defined as the formal acceptance of a proposal by competent authority . It is prepared by Engineering Department.

16. Proposal Contains- Approximate Estimate and Preliminary Plans . Competent Authorities- PWD Minister, Chief Engineer, Superintending Engineer etc.

17.  It is defined as the sanction of Detailed Estimate, Design calculations, Quantities of work, Rates and Costs of work by Competent Authority.  After Tech. Sanction, construction work is started.

18. Authority Power Chief Engineer (CE) Full Powers Superintending Engineer (SE) Upto 1 Crore Executive Engineer (EE) Upto 30 Lakhs Assistant Executive Engineer (AEE) Upto 10 thousands

19. A report is prepared in which total cost required for execution of project is mentioned. According to 5-years plan , finance is sanctioned after administrative approval of the project is Budget Provision.

20. T o pr e pare ch e cklist o f it e ms a s p e r drawings. Prepare Centre-line plan of the structure. Calculate quantities of items of work. E x pr e ss all quanti t i e s i n co r re c t uni t s of measurements. Pre p a r e Esti m a t e a s pe r D r awings & Specifications. Pre p a r e Measu r eme n t S h eet & Abs t r a ct Sheet.

21. Items of work Unit/ Mode 1. Earthwork Cu.m 2. PCC for foundation Cu.m 3. RCC Cu.m 4. Brickwork Cu.m 5. Stone Masonry Cu.m 6. Concrete Cu.m 7. Door & Window Shutters Sq.m 8. Door & Window Frames Cu.m 9. DPC Sq.m 10. Plastering & Pointing Sq.m

22. Items of work Unit/ Mode of Measurement 11. Flooring Sq.m 12. Skirting RMT 13. Centering & Shuttering Sq.m 14. Dado Sq.m 15. Painting/Coloring Sq.m 16. Barbed Wire Fencing RMT 17. Tiled Roofing, G.I. Sheets Sq.m 18. Railing RMT 19. Pipe RMT 20. Wash Basin Numbers

23. Items of work Unit/ Mode of Measurement 21. Site Clearance Lump sum 22. Electric Wiring Points 23. Steel Reinforcement Kg/ Tonne 24. Sand Filling Cu.m 25. 10 cm thick Brickwall Sq.m 26. Nut bolts Kg 27. Laying of sewer pipe RMT 28. False Ceiling Sq.m 29. Cutting of big trees with disposal Nu m be rs 30. Valves Nu m be rs

24. Site Clearance Earthwork in excavation PCC Bed in Foundation RCC in Footing Plinth Beam Column Floor Beams Slab Staircase Plinth Filling BBM for superstructure Flooring Internal Plaster External Plaster Internal Painting External Painting

25. 1. Site Clearance Earthw or k in excavation PCC Bed in Foundation UCR Masonry in Foundation DPC in CM (1:3) Brick Masonry in CM (1:6) Plinth Filling Flooring Internal Plaster External Plaster Internal Painting External Painting

26. Printed Booklet having rates of different works. List of different items of work. Serve s as a guide i n decidin g rate s of various items of work. If rates of contractor differs much from DSR rates, his tender may be rejected.

27. Len g th s shall b e measur e d to the nearest 0.01m. Areas shall be measured to the nearest 0.01m 2 . Volumes shall b e measured to t he nearest 0.01m 3 .

28. (A) PCC 1:4:8 for Foundation Concrete: Cement: OPC Fresh Stock If stored for more than 60 days, test before using

29. (A) PCC 1:4:8 for Foundation Concrete: Coarse Aggregate: Of hard broken stones (about 40mm) Free from dust, organic materials Well graded Lesser voids

30. (A) PCC 1:4:8 for Foundation Concrete: Fine Aggregate: Of coarse sand (about 4.75 mm) Free from dust, organic materials Hard, sharp, angular In dry condition

31. (A) PCC 1:4:8 for Foundation Concrete: Water: Clean & Potable Free from acidic and alkaline matters Free from other impurities

32. (A) PCC 1:4:8 for Foundation Concrete: Proportion: Must be measured using a Box Volume of Box must be equal to volume of 1 bag of cement Take 1 bag cement; 4 boxes Fine Aggregate and 8 boxes of Coarse Aggregate

33. (A) PCC 1:4:8 for Foundation Concrete: a. Machine Mixing: First put Coarse agg.  fine agg  cement in hopper. Let this dry mixture be mixed for at least 4 turns of hopper Then add water slowly Mix this mixture for at least 2 minutes Get a uniform colored and consistent mixture

34. (A) PCC 1:4:8 for Foundation Concrete: b. Hand Mixing: First dry mix Coarse agg., fine agg., and cement on a smooth platform. Slowly add water and mix again. Mix shall be turned 3 times in dry condition and 3 times in wet condition. It gives you a consistent and workable mixture.

35. (A) PCC 1:4:8 for Foundation Concrete: Laying and Compacting: Before laying concrete in trench, sprinkle some water Concrete is laid slowly in layers not more than 20 cm and compacted before putting another layer Before 2 nd layer is laid, make top surface of 1 st layer rough All this process should be free from dust, leaves, earth etc.

36. (A) PCC 1:4:8 for Foundation Concrete: Curing: Concrete must be kept wet for at least 7 days Curing using Gunny Bags or sprinkling water at regular intervals

37. (A) PCC 1:4:8 for Foundation Concrete: Measurements: Measurement shall be taken in cu.m for finished concrete Measurements (Length, Breadth and Depth) shall be accurate up to 0.01m.

38. Len g th s shall b e measur e d to the nearest 0.01m Areas shall be measured to the nearest 0.01m 2 Volumes shall b e measured to t he nearest 0.01m 3

39. No deduction is made for following: Opening each up to 1000sq cm 0.1 square meter Ends of beams, post, rafters, etc. up to 500 sq.cm or 0.05 sq.m in section. Bed plate, wall plate, bearing of balcony (chajja) and the like up to 10 cm depth. bearing of floor and roof slabs are not deducted from masonry.

40. Deductions for Rectangular Opening: Full deduction is made for rectangular openings in masonry walls Deductions = L x H x thickness of wall

41. I t em No. Descri p ti on of Item No. Length Breadth Heig h t or Depth Quantity Remarks

42. I t em No. Descri p ti on of Item Quantity Unit Rate Unit of Rate Amount