Scheduling as Part of the Project Management Effort - Construction Project Scheduling and Control - page 280

progress is then processed as described previously. If the schedule is cost loaded, it
provides periodic information, such as the following:
• Which activities have started (along with the start dates)
• The percent complete of such activities
• Which activities are completed (along with the finish dates)
• Total budget, cost this period, cost to complete, cost at completion ,andcost
variance
• Any other activity-related financial information
This information must be reviewed and approved by the PM and is then forwarded
to the accounting department.
If the project is not cost-loaded, the same procedure must take place through
the accounting system. In this case, the percent complete for each activity must be
entered for the pay period. The accounting system uses the schedule of values and
calculates cost this period, cost to complete, cost at completion, and cost variance.
After the schedule is approved, the cost this period becomes the basis for monthly
progress payments, as described previously.
SCHEDULING AND CHANGE ORDERS
The accounting, estimating, and scheduling departments also handle change orders
(COs), 14 each from its own perspective. In construction, COs are usually inevitable.
However, well-planned and well-managed projects may have few or no COs. Change
orders may be initiated by the contractor or the owner (and are discussed in more detail
in Chapter 13). In all cases, the contractor estimates the cost of the CO and the impact
on the schedule, if any. The owner approves, rejects, or negotiates the contractor's
request. Once the owner approves such a request, the owner issues the CO.
The contractor must then implement the CO in the estimating, scheduling,
accounting, and other management/tracking systems. Managing COs may present
a challenge to the contractor's staff. Change Orders may—and usually do—affect
existing items. For example, two additional floors in a midrise office building may
require the engineer to redesign the columns, the foundation, the main HVAC
unit, the type of elevators, and possibly other items. A deletion of a swimming pool
will alter the amount of excavation and landscaping. If the contractor encounters
“differing site conditions,” the contractor's work plan may have to be delayed or
altered.
What is important to scheduling and project control is implementing the changes
in the baseline schedule (and estimate) so that measuring against the baseline will be
14 Also called variation orders, VOs.