Problem: A small steel frame structure is to be erected and you are to prepare an estimate of the cost based on the data given below and the assumptions provided.
Assumptions: the unloading, erection, temporary bolting, and plumbing will be done by a crew of 1 foreman, 1 crane operator, and 4 structural steel workers with 55 ton crawler crane. The bolting will be done by 2 structural steel workers using power tools. The painting will be done by a crew of 3 painters (structural steel) with spray equipment. For unloading at site, erection, temporary bolting, and plumbing, allow 7 labor-hours per ton for the roof trusses, and allow 5.6 labor-hours per ton for remaining steel. Assume 60 crew hours will be required for bolting. Allow 1.11 labor-hours per ton for painting.
Materials A36 Structural steel Trusses 15tons
Columns, etc. 50tons
Costs:
Structural steel supply: $0.22/#
Fabrication: $450/ton-trusses: $250/ton – other steel
Freight cost: $1.65/100#
Field bolts: 250 @ $0.66 each
Paint: 41 gallons @ $16/gallon
Labor costs: assume payroll taxes and insurance are 80% of labor wage, use the following:
Foreman $24.10
Crane operator $21.10
Structural steel worker $22.10
Painter $20.20
Equipment costs:
Crane $915/day
Power tools $23.40/day
Paint equipment $68/day
Move-in/out $300
Overhead: 40% of field labor cost
Profit: 12% of all costs