Scheduling as Part of the Project Management Effort - Construction Project Scheduling and Control - page 276

1. Provide the labor and equipment cost per unit. For example, if we are placing
concrete for columns, using a pump, the cost is $25.18 per CY (cubic yard)
for labor and $8.88 per CY for equipment. Although there is a basis for how
we derived these numbers, the database does not contain this information or
any details about how we generated these numbers.
2. For the same item, suppose that we are using Crew C-20 8 and this crew can
place 90 CY per day. The cost of the crew is usually listed as part of the resource
information in the database, not for each item. In our case, Crew C-20 com-
prises the following:

Resource Quantity Cost/Hour Each ($) Total Cost Per Day ($)

Labor foreman 1 35.10 280.80

Laborer 5 33.10 1,324.00

Cement finisher 1 39.70 317.60

Equipment operator 1 42.95 343.60

Total Laborers 8 2,266.00

Gas engine vibrator 2 3.80 60.80

Concrete pump 1 92.35 738.80

Total Equipment — 799.60

Total Crew C-20 — 3,065.60

If we check the numbers,

Cost∕CY = Total daily cost∕Total daily production

so

Labor cost∕CY = $2 , 266∕90 = $25 . 18∕CY

and

Equipment cost∕CY = $799 . 60∕90 = $8 . 88∕CY

which is identical to the numbers obtained with the first method.
The second method has two advantages over the first:

1. If the labor or equipment rates change, you can make limited changes to the
labor or equipment rate tables, assuming that you are using a computer. Such
changes should automatically adjust the prices of all items, using these labor or
equipment rates. In the first method, you must manually change every database
item that uses the changed resources.
2. When you are deriving a schedule from the estimate, the first method does not
indicate productivity and, thus, cannot provide the activity duration. The sec-
ond method can provide the activity duration if you simply divide the total

8 This example was taken from RSMeans Building Construction Cost Data (RSMeans 2010)