As discussed in the previous posts, forecasts of future production are calculated by using the actual labor consumption rate and assuming PLANNED resources going forward. But the plans could have been created with incorrect assumptions about the resource consumption. In LBMS, subcontractors commit to a production rate -- not to a crew size -- because actual consumption rate can be highly variable. It is very important to replace the assumption of planned resources with actual resource commitments by subcontractors. We do this using Control Actions.
The Control Action feature in Production Controller is used to change the crew size which is used to forecast future production. This has no impact on the original baseline or current plan. Control actions can be used to calculate how many resources are needed to achieve the desired production rate or they can be used to calculate how fast the subcontractor is going to proceed with their current actual crew size. Any Control Actions should be committed to by subcontractors so that when reports are generated, all forecasts should be based on realistic assumptions of crew size.
The importance of this can be best illustrated by an example. On the left side of Figure 1, a task has started with two resources instead of the planned four. This is a very typical example in real production because subcontractors always tend to start slow and test the operation and (hopefully!) mobilize more resources later. The forecast shows that the work will be finished ahead of schedule assuming that the planned crew of four shows up to work next week. The right side shows the same actual progress, but the forecast has been calculated with a crew of two. The forecast is four and half weeks delayed!
Figure 1: Forecast difference with planned four or actual two resources
Which one is more “accurate”? Of course the one that most closely reflects subcontractor’s intentions. If no production discussions have been initiated with the subcontractor, it is more likely that the work will continue with the same number of people (the figure on the right). I recommend showing the figure on the right to the subcontractor and discussing the best way to prevent the delay. The figure on the left can be shown, as well, to discuss the possibility of going up to the planned crew size. When the subcontractor commits to the bigger team size, the forecast can be updated to match that commitment. Future resource mobilizations should be reviewed each week during look-ahead planning.
The best way to find out if a real production project has been updated correctly is to review the resource calendar for each subcontractor. The resource calendar shows the actual resources to the left of data date and the forecasted resources to the right. If the forecast resources are much larger to the right of data date, mobilization of new resources is expected. If you do not know of any such planned mobilizations, some Control Actions should be updated.
Figure 2 shows a sample resource calendar from a real project. A crew of five has been working on the project. The forecast assumes an additional four resources on the next day and then five more the following week. If these resources are not expected to mobilize, Control Actions should be adjusted to get a more realistic forecast.
Figure 2: Resource forecast in resource calendar
For more information on Control Actions and using the Control Action Log, please refer to the Vico Office Video Training Series on Production Control.
For more resources on Production Control Best Practices, please review:
Part 1: Beyond Start Dates
Part 2: Get the Subs Involved
Part 3: Manpower and Suspensions
To learn more about Vico planning and production control, please utilize the following resources:
Webinar: Planning AND Controlling the Construction Schedule
Webinar: CPM Match
Blog: Superintendents Just Get Vico Office
Blog: What Role Do YOU Play in the BIM Strategy?
Blog: Production Control with Lean Principles
Product: Vico Office Production Controller and FAQs