Chapter 11

1. Chapter 11 Pricing Concrete Work

2. Objectives • Upon completion of this chapter, you will be able to: • Describe the job factors and the labor and management factors that influence the cost of concrete work • Calculate and compare the costs of different concreting methods

3. Objectives (cont’d.) • Describe the factors that should be considered when pricing concrete materials • Identify the factors to consider when pricing formwork systems • Calculate the price per unit area of form systems • Describe the factors that influence the price of reinforcing steel

4. Objectives (cont’d.) • Price miscellaneous items associated with concrete work • Complete the recap and pricing of concrete work using manual methods • Use Excel spreadsheets to price concrete work • Adjust prices and productivities in MC2 ICE estimates

5. Cast-in-Place Concrete Work Generally • Concreting activities categories: • Supply and placing concrete • Construction and removal of formwork • Supply and placing reinforcing steel • Miscellaneous associated items

6. Supplying and Placing Concrete • Costs include: • Cement • Sand • Aggregate • Water • Equipment to mix and transport • Concrete mixing and batching plant • Ready mix concrete

7. Productivity Placing Concrete • Cost of placing concrete in required position • Depends on a large number of factors • Job factors • Labor and management factors

8. Job Factors • Method of placing concrete • Pouring • Hand-operated or powered buggies • Concrete pumps • Conveyors • Combination of two or more methods • Ready-mixed concrete • Delivery rate

9. Job Factors (cont’d.) • Properties of the concrete to be placed • Higher-slump mixtures: sloppier • Lower-slump mixtures: flow more easily • Superplasticizer additives: produce high-slump • Fiber reinforced concrete: improves tensile strength

10. Job Factors (cont’d.) • Size and shape of concrete structures • Large volume concrete “pours” cost less • Placing concrete continuously is more economical • Size and shape will impact placing method • Amount of rebar in forms • Large amounts may call for high slump

11. Job Factors (cont’d.) • Concreting productivity rates • Most contractors maintain a database of historic unit prices • Previous cost reports • Site observations of work in progress • Refer to Figure 11.1

12. Concrete Materials • Prices for ready-mixed concrete • Obtained from local supplier price list • Quotations usually have conditions and extra charges attached • Several issues to consider • Waste factors • Allowances for waste and spillage • Increase takeoff quantities or raise price

13. Formwork • Wide range of methods • Number of costs to consider: • Building and maintaining the form system • Setting up the system • Removing the system • Other costs (e.g., transportation, storage, etc.)

14. Formwork Productivity • Items that impact productivity and cost: • Potential for reuse of a form system • Complexity of formwork design • Use of “fly forms” (“gang forms”) • Number of form ties required for a system • Formwork productivity rates: • Refer to Figure 11.3

15. Pricing Formwork Materials • Material costs include: • Rental or purchase cost of all components • Form hardware cost • Total system price: • Expressed as a price per square foot or square meter of formwork • Calculating price: • Use of computer programs

16. Reinforcing Steel • Includes welded wire mesh and reinforcing bars • Additional cost constituents: • Rebar shop drawings • Raw steel bars • Handling, cutting, bending, and identifying rebar • Transporting the bars to the site • Spacers, chairs, saddles, and ties used • Labor cost of installation

17. Reinforcing Steel (cont’d.) • Reinforcing steel—installation productivity: • Affected by: • Size and lengths of the reinforcing bars • Shapes of the bars • Complexity of the concrete design • Amount of tolerance allowed in spacing of bars • Amount of tying required

18. Miscellaneous Concrete Work Items • Concreting operations • Several associated items • Pricing miscellaneous concrete materials • May not be exactly clear • Example: items of setting slab screed

19. Wage Rates • Basic hourly wages • Equipment operator: $40.00 • Labor foreman: $33.00 • Laborer: $30.00 • Cement finisher: $37.00 • Carpentry foreman: $41.00 • Carpenter: $38.00 • Rebar rodman: $43.00

20. Examples • Concrete Work Recap and Pricing Notes Example 1—House • Refer to Figures 11.9 through Figure 11.11 • Concrete Work Pricing Notes Example 2—Office/Warehouse Building • Refer to Figure 11.12

21. Pricing Using MC2 ICE Software • Items measured in takeoff • Automatically priced from the unit price catalogue • Can be modified • Labor rates: refer to Figures 11.13 and 11.14 • Material prices: refer to Figure 11.15

22. Using the Drill Down Navigation Bar • Estimate Maintenance window • Values may be changed • Set up to show all items measured in takeoff • May be useful to focus on specific parts of the estimate • Refer to Figure 11.17

23. Summary • Main categories for pricing concrete: • Supply and placing concrete • Construction and removal of formwork • Supply and placing reinforcing steel • Miscellaneous items associated with concrete work • Productivity: • Influenced by several factors