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The USACE CPM Schedule Specification

The Specification is full of errors and is biased in favor of specific software.

Just take a look at a few sections, it is a disaster.

2.1 SOFTWARE - Other Than Primavera - If the contractor chooses software other than Primavera P6, that is compliant with this specification, provide for the Government's use two licenses, two computers, and training for two Government employees in the use of the software. These computers will be stand-alone and not connected to Government network. Computers and licenses will be returned at project completion.

  • Requiring such a burden to others while not to Primavera is a mockery of the procurement rules.
  • Why not enforce the same requirements for Primavera P6?  Say contractor is to provide for the Government's use two Primavera P6 licenses, two computers, and training for two Government employees in the use of Primavera P6 along with a sworn certification all requirements have been fulfilled to the best of his knowledge.
  • Training for two dumbs will take forever and the CPM submission will take forever.
  • And what is acceptable training? Most P6 users do not even understand what Spatial Resources are, most P6 users do not understand about consumable resource leveling and many other topics more advanced software can handle. The training would require to teach more than just the software rules, would require to teach them decades of new knowledge the models based on CPM of the 60's cannot handle.
  • Would 15 minutes Power Point fill the requirements for training?  Or two year training would be required?
  • Such a burden is essentially mandating Primavera P6 to all contractors.
  • It is hijacking the Contractor’s planning tools, his means and methods.
  • Claims paranoia does not justify breaking the rules of procurement.
  • If the USACE wants to keep parallel CPM model using the software of their choice then do it but do not force contractor to manage the schedule using tools different to what otherwise he would use.
  • We use more advanced software as we consider P6 software of the 60’s with no new modeling capabilities. It cannot do what we consider basic and essential.
    • Enhanced Resource Planning from Rafael Davila
    • Resource quantity and effort units are not the same and must be defined using different units of measure. Resource Quantity might be 1 ea.  For the same assignment effort units might be 24 man-hours if labor resource.
    • Calculating the required quantity from effort units is not always easy; a simple conversion factor will not make it.  An average makes sense only when all resources are busy all the time; otherwise you might under/overestimate the required quantity.                                                                                                                      .
    • Microsoft Project as well as any other software that cannot account for resource quantity will get leveling of partial workloads wrong. 
    • Work and effort units are not the same and must be defined using different units of measure.  Work might be installing 1,000 ea. bricks.  For the same assignment effort units might be 8 man-hours.
    • Activities status without volume of work is not good enough.  That activity time has elapsed or that some effort has been performed does not mean some volume of work has been done. 
    • Spatial resources: A spatial resource is occupied from the first moment an activity from a group of activities starts until the finish of all activities from that group.
    • Common examples within construction schedules are elevated slab flying forms used in concrete buildings and any equipment to remain in place until a group of activities finish using it such as hoisting equipment and scaffolding.
    • Spatial resources cannot be leveled as renewable resources.
    • Spatial resources can be modeled as consumable resources.
    • Spatial resources are not understood by many schedulers.
  • What will be next, everyone using the same accounting software? Will it be Peachtree or SAP?
    • The USACE should look for better excuses to sanitize their specifications.
    • USACE believes the end justifies the means, this is un-American.

.3.7.1 Workers per Day (WRKP)-  Workers per day are based on the average number of workers expected each day to perform a task for the duration of that activity.

  • Primavera P6 does not provides such field, it uses effort and call them units, it resource level effort which in case of partial workloads can yield unfeasible schedules.
  • As previously shown; calculating the required quantity from effort units is not always easy; a simple conversion factor will not make it.  An average makes sense only when all resources are busy all the time; otherwise you might under/overestimate the required quantity.                                                                                                                    

3.2  BASIS FOR PAYMENT AND COST LOADING - The schedule is the basis for determining contract earnings during each update period and therefore the amount of each progress payment. The aggregate value of all activities coded to a contract CLIN must equal the value of the CLIN.

  • Unpaid remnants of activities in progress can distort the schedule by increasing “out-of-sequence” reporting.
  • Fixing the out-of-sequence can be difficult and onerous; usually will require splitting of activities.  If using Earned Value Management it becomes even harder to fix as the split activities will be missing from the Baseline Schedule.

3.3.2   Activity Durations - Reasonable activity durations are those that allow the progress of ongoing activities to be accurately determined between update periods. Less than 2 percent of all non-procurement activities may have Original Durations (OD) greater than 20 work days or 30 calendar days.

  • Splitting of activities to meet this requirement may result in a resource leveled schedule where the activity chunks become non-contiguous.
  • Critical Path - Show all activities on the critical path. The critical path is defined as the longest path.
    • For Primavera P6 the Longest Path becomes broken when activities are no longer driven by relationships; that is, when activity dates are driven by constraints or resource leveling.

6. e. (8) the HAMMOCK CODE - Indicates that a particular activity does not have its own independent duration, but takes its start dates from the start date of the preceding activity (or node) and takes its finish dates from the finish dates of its succeeding activity (or node). If the value of the HAMMOCK CODE field is “Y”, then the activity is a hammock activity.

  • Primavera P6 does not provide for Hammock Activities but for Level of Effort Activities.
  • P6 Level of Effort Activities child activities must be linked while Hammocks can be defined by two non-linked activities.
  • Hammocks, LOE and Summary Activities are three completely different types of activity.  End Project Finish Milestone and Constraint - The Government is under no obligation to accelerate Government activities to support a Contractor's early completion.

  • The USACE do not understand the concept of Terminal Float and that is required to keep the probabilities of meeting target schedule. Targeting with no reserves is self-defeating strategy. The Government shall duly specify the dates for his activities prior to bidding so that the Contractor can analyze the implications before bidding.
  • This clause places an obstacle to what should be good practice, to plan with some buffers/reserves in the hope of meeting target, it places an obstacle.

3.3.14  Original Durations - Activity Original Durations (OD) must be reasonable to perform the work item. OD changes are prohibited unless justification is provided and approved by the Contracting Officer.

  • Activity duration is usually a function of resource availability and team production rates it is not a fixed number. 
  • A better model shall automatically adjust durations as resource availability and assignments change.  Bid Item Coding (BIDI) - An activity can have only one BIDI Code

  • This is non-sense. Say you have an activity for work on elevated slab that includes work to be done by a team composed of different contractors/subcontractors/teams. The general contractor will do some work related to form-work and reinforcing steel, the plumbing subcontractor will do some plumbing rough-in and the electrical subcontractor will do some electrical rough-in.
  • If you keep the different team members under separate activities [sub-activities] the resource leveling might schedule the sub-activities at different times breaking the need for all to work as a team. Without maximal-lags functionality the tams must be assigned to same activity and therefore the activity shall be assigned multiple BIDI and or CLIN codes.

3.3.17  Percent Complete - Update the percent complete for each activity started based on the realistic assessment of earned value. Activities which are complete but for remaining minor punch list work and which do not restrain the initiation of successor activities may be declared 100 percent complete t allow for proper schedule management.

  • In Unit Price Contracts such as Road Works updating based on % complete makes no sense as the quantities are not fixed. Progress is measured in Volume of Work performed, a field not available in P6.

3.8.3   Forensic Schedule Analysis (Retrospective Analysis) - Prepare an analysis for approval by the Contracting Officer based on industry standard AACE 29R-03.

  • AACE 29R-03 has been questioned by many, among others the ABA – American Bar Association.
  • AACE 29R-03 does not consider the impact of resource constraining in their delay analysis procedures.
  • AACE 29R-03 requires consideration of Longest Path but P6 calculations break under resource constraining.
  • AACE 29R-03 misses to provide guidance on how to consider resource allocation on Delay Claims.
  • The November 2010 draft now states as follows: “[t]he RP/FSAPG [Recommended Practice/Forensic Schedule Analysis Practice Guide] is not intended to establish a standard of practice, nor is it intended to be a prescriptive document applied without exception. Therefore, a departure from the recommended protocols should not be automatically treated as an error or a deficiency as long as such departure is based on a conscious and sound application of schedule analysis principles. In sum, by its own admission, the Recommended Practice is not a standard.  Interim Completion Dates and Constraints - Constrain contractually specified interim completion dates to show negative float when the calculated late finish date of the last activity in that phase is later than the specified interim completion date.

  • Float is a parameter resource leveling algorithms use; negative float calculation interferes with it, on poorly written software and should not be mandated in any case prohibited.
  • Negative float is a distraction to delay analysis to the extent many delay analysis procedures prohibit its use. Other procedures adopt the negative float calculation and go to extreme or complex manipulation of the analysis as to scope with it.
  • A very old bug in P6 that hasn’t been fixed for ages now, if you used multiple different calendars with different hours in the schedule, that may generate a negative float, especially if there are milestones in the schedule, it seems that the late date of the milestone jump to the last working hour of the previous working day in the calendar.
  • Using the resource dependent activity type with a resource calendar different than the activity calendar may lead also to negative float, this is another bug that primavera needs to work on.
  • The USACE shall be able to see by comparing to Contract Baseline how much the current schedule is ahead or behind.
  • Better software makes the calculation as a separate field, but P6 does not.

3.3.15    Leads, Lags, and Start to Finish Relationships - b. Start to Finish (SF) relationships are prohibited.

  • It bans possible genuine needs.
  • The need for SF relationship occurs when the start of a successor must happen before the predecessor finishes. It is most common when a process changes hands and there must be a transition period.
  • Say you have two activities, one for Site Security by Contractor and another for Site Security by Owner. Contractor cannot finish [stop] providing site security until security by Owner is in place. Maybe the USACE do not want the schedule to disclose that if start of Site Security by Owner the finish of Site Security by Contractor is to be delayed.
  • Banning of procedures that might be necessary to get better models is not a good idea. That these occurrences happen very rarely is no excuse to ban them. Better specifications do not ban suspicious logic but put a flag and ask for the justification.

3.3.18 Remaining Duration - Update the remaining duration for each activity based on the number of estimated work days it will take to complete the activity. Remaining duration may not mathematically correlate with percentage found under paragraph entitled Percent Complete.

  • Remaining Duration can easily be manipulated by unscrupulous schedulers looking to sequester available float.
  • For true duration type activities the duration represents time elapse that will happen as time elapses.  For most other activities duration is a function of Volume of Work, resource assignments and their production rates. Good Practice requires to make the calculations based on these parameters. As-Built Drawings - If there is no separate contract line item (CLIN) for as-built drawings, cost load the "Submission and approval of as-built drawings" activity not less than $35,000 or 1 percent of the present contract value, whichever is greater, up to $200,000. Activity will be declared 100 percent complete upon the Government's approval.

  • This is too much of an arbitrary value. If there is no CLIN of whatever activity is required the value shall be a realistic estimate value that shall be submitted and duly justified. O & M Manuals - Cost load the "Submission and approval of O & M manuals" activity not less than $20,000. Activity will be declared 100 percent complete upon the Government's approval of all O & M manuals.

  • This is too much of an arbitrary value. If there is no CLIN of whatever activity is required the value shall be a realistic estimate value that shall be submitted and duly justified.

3.5.4 Network Diagram - The Network Diagram is required for the Preliminary, Initial and Periodic Updates. Depict and display the order and interdependence of activities and the sequence in which the work is to be accomplished.

  • Network diagram on large networks with thousands of logic links are for practical purposes impossible to trace. In any case the logic of the network should be made available through a table or report that shows all logic links and their properties such as: preceding activity, successor activity, if SS/SF/FF/FS lag type if Time/Volume_of_Work, lag calendar, if critical, if driving, if it is a resource dependency temporarily created by resource leveling process, if broken by out-of-sequence progress, just to name a few.
  • CPM is about logic otherwise it is a GANTT CHART, all relevant information about links shall be disclosed in a table as it gives more information than a network diagram.

3.8.2 Time Impact Analysis (Prospective Analysis) - Prepare a time impact analysis for approval by the Contracting Officer based on industry standard AACE 52R-06.

  • The reference starts by stating the following: PURPOSE - This Recommended Practice for Time Impact Analysis (TIA) is intended to provide a guideline, not to establish a standard.
  • Everywhere the reference warns that a TIA is a simplified procedure with limited application. To require TIA for every time extension in the prospective makes no sense. There are other Prospective Analysis techniques that are better suited for other common scenarios where TIA is not valid.


  • What I got are old specifications, it is difficult to get up to date specifications.
  • These old SDEF Specifications are faulty, are biased toward CPM applications that make use of poor selection of fields. This has the effect of banning better applications.
  • Better and more modern software such as Spider Project do not make use of fields such as Original Duration a bad practice of old software. Better and more modern software do not make use of Level of Effort activities as they use better implementation of Hammock activities, a different monster.
  • It is The Impossible Dream to expect a mere transfer of some data field will allow different software to calculate equal.
  • When will the USACE will realize SDEF is a waste of time and effort, it is not reliable?


  • In Government Contracting where the Bidder has no real negotiating power Band Name Specifications is wrong, is against competition and free market and have a corruption smell.
  • SDEF for CPM is unreliable, the idea is good for transferring of static data such as accounting data but it will not transfer a CPM model between different software.
  • Too strict CPM specifications are an interference with the Means and Methods of the Contractor. If USACE wants to play the Contractor then better be the Contractor.
  • Specifications written by rookies can be damaging to all parties.
  • Wise specifiers require and review the Schedule as informative and make no judgement about the details. They keep the Means and Methods to where they belong while keeping their right to be informed.
  • At the end of the day in any claim the burden of proof is on claimant.


ER 1-1-11 Progress Schedules

ER 1-1-11 Progress Schedules and Network Analysis Systems

Is an old specification dating back to 1995, it is 22 years old as of 2017.

SDEF - Defense Technical Information Center

Testing reports available are equally old, and seems like many software developers abandoned the idea long ago.  Maybe they figured it out it is impossible to make P6 [or whatever the yardstic is] behave as more advanced software can do.

USACE 2015 cpm specifications

It is not unusual for members

It is not unusual for members of these agencies not to discuss every item on its merits and to divert attention before they finally chicken out of the discussion.

Market Place

Primavera P6 and Microsoft Project books, on-line video training courses and training material available from an internationally recognised publisher and PMI accredited REP. Teach yourself using on-line or book based learning or run your own in-house or public PMI accredited courses.