Chapter 10
Pricing Excavation and Backfill
Objectives
• Upon completion of this chapter, you
will be able to:
– Describe the job factors and the labor and
management factors that influence the
price of excavation and backfill operations
– Use historic productivity rates to calculate
the unit price of labor and equipment for
excavation and backfill work
Objectives (cont’d.)
– Calculate the price of gravels and other
backfill materials
– Calculate trucking requirements for hauling
excavated material and gravels
– Complete the recap and pricing of
excavation and backfill work using manual
methods
– Use Excel spreadsheets to price
excavation and backfill work
Excavation Equipment and Methods
• Specialized excavation contractors
– Concentrate on a single construction type:
• Vast array of excavation equipment
• Wide scope of work
– Common activities:
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•
•
•
Site cut and fill operations
Basement-type excavations
Trench excavations
Pit and sump excavations
Excavation Equipment and
Methods (cont’d.)
• Equipment transportation expenses:
– Priced on an item-by-item basis
• Site cut and fill operations:
– Equipment depends on project scale
• Basement excavations:
– Often performed with a track backhoe
– Large basements: one or more track loaders
Excavation Equipment and
Methods (cont’d.)
• Trench excavations:
– Smaller trenches: trenching machines
– Larger trenches: backhoes
• Pit and sump excavations:
– Mostly performed using backhoes
• Hand excavation:
– Rarely used
Excavation Productivity
• Job factors:
– Type of material excavated or backfilled
– Moisture condition of materials
– Weather conditions expected
– Site access and project size/complexity
– Distance to haul materials for disposal
– Availability of gravels and fill materials
– Wage and price levels at the job location
Excavation Productivity (cont’d.)
• Labor and management factors
– Quality of job supervision
– Quality of job labor
– Motivation and morale of workers
– Type and quality of tools and equipment
– Experience and records of similar past
projects
Excavation Work Crews
• Labor price per unit of excavation work
– Elements to consider:
• Number of workers that comprise the work
crew and their trades
• Wage rates of trades involved
• Probable productivity rate of crew or equipment
they are operating
• Productivity time factor
Productivity Rates
• Sources:
– Provided in publications (e.g., Means
Building Construction Cost Data)
• Use with caution: general reflect ideal
conditions
– Also available from manufacturers
– May be compiled from contractor’s own
projects
Figure 10.3 Productivity of Hydraulic Excavators
(Delmar/Cengage Learning)
Figure 10.4
Sample Data Record
(Delmar/Cengage Learning)
Excavation Materials
• Mostly comprise gravels and fill
materials:
– Required to meet designer’s specifications
• Backfilling
• Base courses under slabs and paving
• Pricing components:
– Supplying material to the site
– Spreading and compacting
Swell and Compaction Factors
• Excavated soil or gravel:
– Less dense
• Swell factor:
– Occupies more volume
• Compaction factor:
– Allowance for extra material required to fill
volumes with compacted material
Calculating Trucking Requirements
• Determine optimum number of trucks
required to transport materials
– Formula:
• Number of Trucks Required = Unloading Time/
Loading Time + One
– Example: Gravel Supply Pricing
• Refer to Pages 234 and 235
Additional Examples
• Excavation and Backfill Recap and
Pricing Notes
– Example 1—House
• Refer to Pages 235 through 240
• Excavation and Backfill Pricing Notes
– Example 2—Office/Warehouse Building
• Refer to Pages 240 through 244
Summary
• Many subcontractors perform
excavation and backfill work
– Most specialize in some aspect
• Common methods:
– Site cut and fill operations
– Basement-type excavations
– Trench excavations
– Pit and sump excavations