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Scheduling Tricks and Traps

Tricks, Traps, and Ploys in Scheduling Claims

Project schedules often go awry. What begins with a realistic plan can quickly snowball into a major dispute. Below are a number of tips to minimize delays and scheduling claims.

Critical Path Schedule
Most project Owners require a CPM (critical path) schedule on large, complex or risky projects. The CPM schedule assures the Owner that the Contractor has a viable plan to complete the project on time. It enables you to track progress to quickly identify delays, provides a blueprint for recovery of lost time, and protects against unwarranted delay and impact claims.

Your first step is a well-written specification, which should require the following:

  • Submittal of electronic schedule files
  • Joint schedule review by the Owner’s representative, and the Contractor’s scheduler and superintendent
  • Monthly schedule updates with narrative reports
  • Daily field reports from the Contractor’s superintendent and all subcontractors
  • Recovery schedules if work falls behind
  • Time impact analyses to justify time extension requests
  • Partial withholding of progress payments for failure to comply

Software Tricks and Traps
By utilizing little-known features of Primavera P3 or Microsoft Project, Contractors can distort the schedule to hide delays or fabricate a claim. More often, CPM concepts or software features are not fully understood, inadvertently creating an inaccurate schedule. You need to know how to recognize these electronic ploys, or bring in professional assistance to find hidden traps.

Action if Delayed
Despite everyone’s best efforts, projects can still experience unforeseen delays. If the delay is the responsibility of the Contractor, Owners should require a recovery schedule. If the Owner causes the delay, insist on a prompt, detailed, joint review of the problem. First, try to re-sequence operations to avoid a delay. If necessary, compare the acceleration cost to the delay cost and choose the optimum solution. Also, take special care when preparing global settlements.

Defense of Scheduling Claims
When a scheduling dispute arises, insist on a detailed time impact analysis, including a comparison of as-planned with as-built. For weather delays, require a comparison to NOAA records. Require submission of all supporting documents (daily reports, timecards, etc.), and a narrative that explains entitlement and how the events or actions by the Owner caused the delays and subsequent costs. To discourage fraud, require certification of all claims.

Through a proactive approach, you can maintain control of your project schedule and adapt to changes without excessive costs. Please contact our office for assistance in reviewing a Contractor’s schedule or improving your own schedule tracking process.

Tips to Avoid Traps
Below are a few tips from our Schedule Review Checklist for project Owners:

  • Out-Of-Sequence Logic: Use the ‘Retained Logic’ option instead of ‘Progress Override’ to avoid invalid progress and delays.
  • Excessive Lag: Lags greater than one week need to be verified and possibly changed to a separate activity.
  • Incorrect Actual Dates: Verify the actual dates. Wrong dates can be used to hide delays or set up for a claim.
  • Multiple Calendars: When analyzing the critical path, unexplained variations in float may be due to multiple calendars.
  • Erroneous Constraints: Check if constraints are invalid or used incorrectly. Constraints can unnecessarily delay the start of critical activities, falsely create another critical path, or cause negative float. Do not use Mandatory Start and Finish constraints, or the ‘Zero Total Float’ constraint.
  • Auto-Cost Rules: Select the ‘Link Remaining Duration and Schedule Percent Complete’ option. If you don’t, separate updating is required that could result in error if one is overlooked.
  • Scheduling Report: Run P3’s Scheduling Report to review constraints, open-ended activities, out-of- sequence logic, and statistics.
  • Check The Data Date: Verify that the report Data Date is correct for the current status.
By |August 25th, 2015|Uncategorized|

Construction Scheduling

by Steve Pinnell, Principal

Importance of Scheduling
A good schedule will save time and extended overhead costs, avoid delays, eliminate most overtime, ensure a more efficient construction sequence, and substantiate claims for owner delays or impact. Scheduling software is helpful but will not guarantee a good schedule. Schedulers, including project managers and superintendents, need to master critical path scheduling (taught in an intensive one-day seminar). A working knowledge of the software and access to an expert will aid in special applications or resolving problems.
The project team is often too busy mobilizing and running the job to spend enough time on scheduling. Because they need to “own” the schedule, I advise using a scheduler to assist the project team in preparing their schedule. An expert will prevent staff wasting time struggling with software and the problems that occur when updating or trying to prove owner-caused delays.

Crew Chases
   Resource leveled schedules are desirable, but they are too much work for most projects. Instead, show “crew chases” by tracing major pieces of equipment (cranes, scraper fleet, etc.) and key labor crews from activity to activity. This prevents scheduling them for two places at the same time or leaving gaps which cause multiple mobilizations, lowered morale, and poor productivity.

Subcontractor Scheduling
To schedule your subcontractors: (1) prepare an initial schedule with all subcontract work; (2) get each subcontractor’s commitment to meet their dates; (3) save some float in the schedule for unexpected problems; (4) write your subcontracts to clearly define the subcontractors’ scheduling responsibilities; and (5) hold everyone (including your crews) to the agreed schedule.
If you are a subcontractor, schedule and resource load all of your projects on a master schedule at your home office. Otherwise, you may run short of work or become overcommitted, delay some projects, and be back charged.

Monthly Updates
Update your schedule every month: record actual start and finish dates, percent complete or days remaining of ongoing activities, delays or impact, and revisions if needed.

Short-Interval (Look-Ahead) Schedules
Tie your superintendent’s weekly short-interval schedules to the master schedule to avoid overlooking critical activities. Use an Excel™ spreadsheet or Microsoft Project™ to show actual progress for the previous two weeks, planned work for the next three weeks, and the previous month’s schedule activities below the activities for the current schedule.

Scheduling for Changes and Delay
Revise the schedule as changes occur or it will become inaccurate and unusable, which may preclude time extensions and compensation. Use fragnents (network diagrams of only the affected work) to identify and explain delays to the critical path.
Analyzing scheduling claims may require a Detailed As-Built Schedule. This schedule economically and quickly creates a very detailed and accurate as-built schedule from the basic job records (daily reports, correspondence, inspector’s logs, cost reports, and other record of progress, impacts, crew size, weather, etc.). Spreadsheet macros make this a relatively fast process. For details, visit our web site

Steve Pinnell has provided scheduling and claims expertise on over a thousand projects for several hundred contractors since 1975. He is the author of HOW TO GET PAID for Construction Changes. See our website for details.

By |August 25th, 2015|Uncategorized|

Reviewing and Approving Contractor Schedules

Reviewing and Approving Contractor Schedules

As many public works agencies have learned, you must obtain adequate contractor schedules to monitor progress and to avoid unnecessary delays and claims.

Recommended Scheduling Specifications
Pinnell/Busch’s recommended procedures for controlling construction schedules and defending scheduling claims by public works agencies and other project owners include:

  1. All contracts should require contractors to submit a schedule for approval, with a preliminary schedule at the pre-construction conference and an approved final schedule before the first progress payment.
  2. Monthly updates should be mandatory and enforced, with revisions when delays occur or scope changes.
  3. Larger projects need a CPM schedule with a timescaled network diagram. Activity listings should include activity numbers, descriptions, durations, scheduled early and late start / finish dates, relationships, constrained dates, total float, and the subcontractor or general contractor crew responsible for each activity.
  1. Very large, time-critical projects require resource loading, justification of constrained dates, identification of work areas, productivity assumptions for critical activities, and activities for procurement, submittals, traffic detours, start-up, etc.

Review and Approval Procedures

    1. Your best approach to schedule review is partnering and a joint review with the schedule pre parer and superintendent. Trace each critical or near-critical logic chain through to completion. Discuss expected crew size and capacity, work quantities and production rates. Carefully record all assumptions, as you may need to use them later to defend against scheduling claims.
    1. Check for impractical logic, crew overlaps, overly optimistic durations, missing activities or relationships, unseasonable scheduling of weather-sensitive work, lack of crew chases and excessive demands on agency furnished resources, etc.
  1. Then, jointly re-review the schedule in a “brainstorming” mode to identify improvements.

Schedule Monitoring and Recordkeeping
Field personnel need to understand scheduling fundamentals and the contractor’s schedule. They need training in what to record, and how to monitor, record, and report progress and discrepancies.
Monthly schedule updates should include: actual start and finish dates, percent completes or days remaining, and minor revisions to completed or pending activity durations and logic. Note periods of intermittent progress and the reasons, along with weather delays, alleged impacts and problems, and added activities for change order work, etc. Handle schedule updates and revisions in a partnering mode with joint meetings and timely approval, or clear rejection with detailed reasons. Record detailed progress notes independently of the contractor’s records.
   Change order approval should include review and approval of the contractor’s” fragnet” schedule showing the extra work and any impact. It’s cheaper to approve time extensions when negotiating change orders concurrently with the work, as most contractors will forego extended overhead claims in exchange for receiving an adequate time extension and their direct costs.

Defense of Scheduling Claims

  1. When delay or acceleration is alleged or anticipated, increase monitoring and recordkeeping per your Change Order Management Plan.
  2. Respond promptly to time extension requests, to avoid constructive acceleration claims, while requiring the contractor to substantiate alleged delays.
  3. Review scheduling claims promptly — even if that requires bringing in additional personnel. Identify the issues and legal theories, and verify all the facts. You may want to create a “detailed as-built schedule” — a timescaled activity barchart/network-diagram based on day-by-day, detailed job records.
  4. Compare the as-planned schedule to the as-built and create a “would have been, but for. .. ” schedule that identifies contractor and owner / designer delays, as well as non-reimbursable (e.g., weather) delays.
  5. When delay or accelerated impact costs and labor inefficiencies are claimed, use a combination of the many new and effective methods of analysis now available.
  6. If you believe the responsibility or impact is partially yours, partner the solution promptly.
By |August 25th, 2015|Uncategorized|

Critical Path Scheduling: An Overview and a Practical Alternative

American Society of Civil Engineers
Civil Engineering Magazine, July 1980
By Steven Pinnell

Although critical path scheduling (CPM/PERT) was developed in the late 1950s and has been taught in seminars and university courses since then, it is used by few and understood by even fewer. Yet it is an extremely powerful and adaptable — but simple — tool.

The reasons for CPM/PERT’s limited use seem to be a failure to appreciate its simplicity and a misconception that computers and scheduling specialists are necessary for its use. Project managers have either attempted to plan and control their jobs with bar charts or have surrendered their basic role of planning, scheduling and controlling progress to a machine and a technician. Subsequent failure of computerized schedules to reflect the thinking of those doing the work often results in schedules that are not or cannot be followed. In addition, many managers are unable to cope with the reams of data that the computer spews forth. The end result is that most projects are still being planned with bar charts — if at all.


There is a method of CMP/PERT scheduling that is simpler, easier and just as powerful as computerization. It is the time-scale arrow diagram — a method used successfully by this firm for years on all types of projects. It’s been taught to hundreds of people who have found it vastly superior to computer printout on most jobs. The following discussion presents a brief overview of CPM/PERT, then explains how and when to use the time-scale arrow diagram method of CPM scheduling.


CPM (Critical Path Method) and PERT (Program Evaluation and Review Technique) were both developed in the late 1950s on very large computers for massive projects. PERT, developed for research and development projects, focused on major events (called milestones) and used probabilities to calculate the most likely time between milestones. CPM, oriented toward construction, focused on those activities required to accomplish a project by using one estimate of activity duration instead of the three used in PERT.

Although there has been a mind-boggling proliferation of CPM and PERT variations, the two techniques have become quite similar. CPM users have adapted the use of the milestone to highlight the beginning or end of a major phase of work. And now PERT users seldom use three estimates of activity duration because one is plenty of work and not many have the time or patience to estimate two more durations when the results are scarcely better.

Today, few civil engineers or contractors use PERT, and those who do should recognize that the techniques are essentially the same. Therefore, the following discussion focuses on CPM.

Basic steps

There are three basic steps in preparing a CPM schedule: 1) planning (or diagramming), 2) estimating of activity durations, and 3) scheduling (or computing).

First, one must plan the job, usually by laying out the activities in sequence on a piece of paper. This is the network diagram; it defines the activities and their relationship. The two types of network diagrams are the arrow diagram and the precedence diagram. Either of these, or some variation, must be prepared even if the schedule is eventually computerized.

Second, one must assign time durations to each activity. This step is almost as difficult as the first step and also must be done manually.

Third, only when the diagram is prepared and durations assigned, can one compute the critical path, early start (ES), late start (LS), early finish (EF), late finish (LF), float, and total project duration. This is the easiest step as it requires only simple mathematics — addition and subtraction. It can be done by computer.

There are four methods of computing the critical path. Two are computerized (i-j node and precedence) and two are non-computerized (manual computation directly on the network and time-scale computation with the network diagram).

i-j Node Computing

CPM was originally developed using the i-j node method. In this method, each activity is identified to the computer by its beginning (i) node number and its ending (j) node number. These two numbers (i-j) uniquely define each activity and the relationship between them. For example, if activity B follows activity A(as in Fig. 2) then the j (ending) node number of activity A is the i (beginning) node number of activity B (as in Fig. 1).

lt is nearly impossible to determine accurately the complex relationships between activities of a major project from just a table of activity descriptions and their i-j nodes (such as Fig. 1). Consequently, activities first are laid out on a network diagram that graphically shows the relationship between them. This is called arrow diagramming, as an arrow represents the activity (with no time-scale) and a circle (or node) at each end contains the i-node number and j-node number. A relationship between two activities that cannot be shown by directly connecting the arrows is indicated by a dotted-line arrow, called a dummy arrow (Fig. 2).

Precedence Computing

The precedence method is a new approach to CPM scheduling; it assigns one number to the activity itself and simply lists all preceding activities, making it much easier to update and revise than the i-j node method (see Figs. 3 and 4).

Precedence diagramming uses a box instead of an arrow to represent an activity. A solid line goes from the back of the preceding activity to the front of the following one to show relationships, making the precedence diagram much easier to draw and revise than the arrow diagram (see Fig. 4).

Although the precedence diagram appears to be quite different than the arrow diagram, they are really quite similar (as shown in Figs. 5-8).

Manual Computation

One of the first non-computer scheduling methods was developed by Prof. John Fondahl of Stanford University in 1963.Non-computer methods are easy to use, requiring only a network diagram and basic skills in addition and subtraction to compute the ES, LS, EF, LF, float, and total project duration.

It has been found to often be cheaper and faster to manually calculate the critical path than to input data into a computer, make the run, debug it, and rerun. Incidentally, if one doesn’t computerize, there is no need for the nodes (circles) and i-j numbers except to highlight a milestone. This will significantly speed drafting (the typical activity arrow and notation is shown in Fig. 9).

The ease of manual CPM schedule computation can be illustrated with the example network (seen in Fig. 10).

Forward Pass

The first step is to start activity A at the beginning of work day 1 (Fig. 11), which is the ES for activity A. If activity A starts the beginning of work day 1 and takes 5 working days, its EF will be 1 + 5 = 6 (the beginning of work day 6, which is the same as the end of work day 5; see Fig. 12). If the earliest that activity A can finish is (the beginning of) work day 6, then the earliest that activities B and D can start is (the beginning of) day 6 (ESB = ESD = EFA = 6); see Fig. 13.

Since activity B can start the 6th day and takes 6 days, the earliest it can finish is the 12th day (EFB = ESB + duration = 6 + 6 = 12). Also, activity D can start the 6th day and takes 8 days so it can’t finish before the 14th day (EFD = ESD + duration = 6 + 8 = 14); see Fig. 14.

To compute the Early Start for activity C, one must consider what activities have to finish before C can begin and what is the earliest that they will finish. From Fig. 15, it is apparent that activities B and D both must be finished before C can start — and that the earliest that they will be finished is day 14 (ESC = latest EF of B or D = 14). Therefore the ES for C (and also E) is 14.

The computations continue:
1) EFC = ESC + duration = 14 + 5 = 19
2) EFE = ESE + duration = 14 + 2 = 16
3) ESF = latest of EFC or EFE = 19
4) EPF = ESF + duration = 19 + 4 = 23 (see Fig. 16).

Backward Pass

This completes the “forward pass,” which gives the early start, early finish, and total project duration. The next step is the “backward pass,” which gives the late start, late finish and float. To begin the backward pass, set the late finish of the last activity equal to the early finish (LFF = EFF = 23). The earliest the project can finish is (the beginning of) the 23rd day. The latest the project can end is also (the beginning of) the 23rd day. If activity F takes 4 days, then the latest it can start and not delay the project is the 19th day (LSF = LFF – duration = 23 – 4 = 19) (see Fig. 17).

If day 19 is the latest activity F can start and not delay the project, then day 19 is also the latest that activities C and E can finish and not delay activity F (and thus the project). Therefore, the late finish of both activities C and E is day 19 (see Fig. 18).

From here, it is simple subtraction to determine that:
1) LSC = LFC – duration = 19 – 5 = 14
2) LSE = LFE – duration = 19 – 2 = 17
3) LFB = LSC = 14
4) LSB = LFB – duration = 14 – 6 = 8
5) LFD = earliest of LSC & LS = LSE = 14
6) LSD = LFD – duration = 14 – 8 = 6
7) LFA = earliest of LSB & LSD = LSD + 6
8) LSA = LFA – duration = 6 – 5 = 1

This completes the “backward pass” and gives the late finish and late start of each activity (see Fig. 19).

Computation of Float

Float is the number of days between either the early start and late start or the early finish and late finish (float = LS – ES = LF – EF). Activities with an early start equal to the late start have zero float and are therefore critical. Note that activity A is critical (LSA – ESA = 1 – 1 = 0 = LFA – EFA) as is activity D (LSD ESD = 6 – 6 = 0), activity C (LSC – ESC = 14 – 14 = 0), and activity F (LFE – EFE = 23 – 23 = 0). However, activity B has 2 days float (LSB – ESB = 8 – 6 = 2 = LFB – EFB = 14 – 12 = 2), and activity E has 3 days float (LSE – ESE = 17 – 14 = 3).

Conversion to Calendar Date

The final step is to convert the computed work days for ES, LS, EF, & LF to calendar dates. This can be accomplished by providing a simple conversion table on the network diagram or even developing a table with the calendar dates. Conversion to calendar date is tedious, but for only one project it is probably cheaper and faster than to: 1) learn how to use a particular computer program, 2) key punch the date, 3) make the computer run, and 4) debug the data so that it runs correctly.

Time-scale Arrow Diagrams

Fortunately, there is another non-computer alternative to the time-scale arrow diagram. The initial step is to draw the first activity to scale. As seen from Fig. 20, activity A begins on work day 1 and ends (the beginning of) work day 6.

Next step is to draw the activities directly following activity A (see Fig. 21). The natural tendency is to draw activity C starting day 12, directly after the finish of activity B. However, activity C is also dependent upon activity D and therefore can’t start before day 14. Therefore, activity C has a two-day float arrow from activity B and a vertical relationship (dummy) arrow from activity D
 (see Fig. 22).

Activity E starts immediately after activity D is completed, then continues as a float arrow until the end of C. Activity F follows C & E and takes 4 days.

A quick review of this network diagram will reveal that Activity B has 2 days float; activity E has 3 days float; and activity path A, D, C, F have zero float and is therefore critical. In addition, one can quickly determine early start and early finish days (ESF = 19, EFE = 16, ESB = 6, etc.).

Comparison with Bar Chart

It’s interesting to compare the time-scale arrow diagram with the bar chart (Fig. 24). Both are easy to read and understand. The time-scale arrow diagram takes less space, shows the relationship between activities, and shows float.

It has been found that the time-scale arrow diagram is but slightly more difficult to prepare than the bar chart and can be just as simple. Yet it has many advantages over the bar chart.

But the bar chart is still a good technique for projects without a critical path. For example, a process machine shutdown is often more dependent upon resources than upon a certain sequence of activities. In such cases, either a bar chart or a modified time-scale arrow diagram may be used.


Alleged criticisms of the time-scale arrow diagram are:
1) too hard to draw
2) too difficult to update
3) too long a drawing
4) too little information

None of these criticisms have been found to be true.

First of all, one should remember that the vast majority of work in CPM scheduling is in gathering and evaluating information — not drafting the network. Secondly, a network diagram always has to be drawn in order to schedule a project; it also frequently is erased and redrawn before it is satisfactory. Although time-scale diagrams are more work to draft and change than non time-scale diagrams, the extra effort is negligible. Besides, drafting techniques developed by Pinnell Engineering more than compensate for the additional work. In fact, they make time-scaling easier than normal methods of non time-scale networking.

One time-saving technique is to eliminate the i-j nodes (they aren’t needed unless the schedule is computerized with the i-j method). The amount of work required to draw the circles is much greater than normally realized. Also, the circles clutter up the diagram, making it difficult to read. Instead of circles to mark the beginning and end of activities one need only use arrowheads to give a sense of flow.

Another time-saving technique is to draft the network on fade-out grid paper (a translucent grid paper with light blue lines at 1-in. or 25-mm intervals). A blueline preprint drops out the grid lines, leaving only items drafted onto the network. The grid lines greatly facilitate drafting the network because:
1) horizontal lines are easily drawn
2) activities are easily and evenly spaced 1-in. apart, with subnetworks separated by 2-in. (50 mm) for clarity, and overlooked activities inserted at 1/2-in. spacing
3) lettering is fast because the small grid lines provide an adequate guide
4) time-scaling is simplified – if a scale of 1-in. per week is used, then 1 working day = two 1/10-in. grid lines on a 10 x 10 grid, or if a scale of 1-in. per month is used, then 1 week equals approximately two 1/8-in. grid lines
5) drawing of consistently sloped angle portions of activity arrows is facilitated as one can easily lay out a 1:10 or 1:8 slope.

Difficult to Update

One of the most frequent criticisms of the time-scale arrow diagram is that it is too time consuming to update when work falls behind or gets ahead of schedule.

First, there is no more need to redraw a time-scale arrow diagram. An out-of-date time-scale arrow diagram is at least as valid as the non time-scale arrow diagram.  Second, the preferred method of showing deviation from plans is not to redraft the network (obscuring the original plans and deviations) but, rather, to show a vertical status line.  This starts at the revision date, drops vertically to the first activity, jogs horizontally to the percent complete of that activity arrow, and continues to the bottom of the page(see Fig. 25 for an example of an update line).

As can be seen in Fig. 25, “Pour Concrete” is 4 days behind, “Excavate Footings” is on-schedule, and “Mechanical & Electrical Work” is one week ahead.  This provides an excellent guide for the project manager as to what needs expediting.  Naturally, if the project gets too far ahead or behind schedule – or if there are major logic changes – redrafting is necessary in order to maintain the usefulness of time-scale.

A classic example is the computer-generated, time-scale arrow diagram that starts over the project engineer’s desk, runs across the wall, around the corner into the next office, and clear down to the other end of the job trailer.

One need not do this.  The smallest necessary scale is usually 1-in. per week.  This allows one working day equal 2/10-in. (10 x 10 grid paper) and is enough to draw a very short arrow with an arrowhead for those infrequent activities that require only one day.  If some activities take less than a day, they can be combined with others.  If there isn’t room to put the description directly over the activity, then it can be put up out of the way with a leader (see Fig. 26). Sometimes, of course, one inch per week doesn’t give enough room (as in a paper machine shutdown).  In these cases, overall project duration is usually quite small and the scale can be expanded.

At 1-in. per week, a one-year project becomes rather unwieldy (52-in. plus 2-in. margins or 1320-mm plus 50-mm), and a two-year project becomes impossible.  One solution is to stack one half of the schedule over the other on the same sheet of paper.  Using a 30-in. (762-mm) wide sheet with ½-in. margins top and bottom – plus 2-in. between the halves – 14-in. (355-mm) widths are available for each half.  Since some activities will be separated by ½-in. and a few by 2-in., there is room for about 20 concurrent activities at the same time (which is adequate for most projects).  If a schedule is stacked, plenty of room must be left between halves so that the two are already delineated.

Another solution is match lines and two or more sheets.  Although this may be required in some cases, it is obviously not as desirable as viewing the entire schedule in one piece.

Yet another solution is to break the scale, drafting the first part at 1-in. per week and the rest at another scale or not-to-scale.  This often works well, as it is best to avoid too much detail too far into the future because: 1) one seldom has sufficient time, and 2) plans will probably change by the time one gets closer to doing the work.

The final solution is to use a different scale.  One inch per two weeks works very well and even one inch per month does well for many projects.  This is about as far as one need go, as a 4-ft. (1.2 m) drawing can then cover about four years.

Too Little Information

The time-scale arrow diagram does have some limitations, however.  Assume an average vertical spacing of 1 in., an average activity length of 1½ weeks at in./week, and 25% of the space unused due to the organization of the network. A large drawing (36 in. x 60 in. or 1524 mm x 914 mm) can have up to 1000 activities and a medium-sized drawing (30 in. x 36 in. or 762 mm x 914 mm) can have up to 500 activities.

For projects up to $30 million, Pinnell Engineering has seldom exceeded 300 activities on anyone network. It is best to have additional detail in subnetwork schedules tied to the master schedule but prepared and maintained by the organization responsible for that portion of the project. Not only does this reduce the information required, it places the scheduling responsibility where it belongs.

This firm does not, in fact, recommend having over 500 activities on a network (at anyone time) as managers cannot and should not grapple with such detail. However, as the project progresses, completed activities are dropped off and new activities added so that the total number of activities may be several thousand over the life of the project.

Advantages of Time-Scale Arrow Diagram

Rather than being inferior to computer scheduling, timescale arrow diagramming actually has several distinct advantages; these are:

  1. greater flexibility
  2. quicker and clearer communication and visualization
  3. faster and cheaper preparation
  4. more power

Good graphics (time-scale arrow diagram) implies relationships between two concurrent activities or shows an approximate relationship between activities that computer printout could never do. Many work activities (e.g., Mechanical embedded in concrete), take only a short time to accomplish, must occur sometime concurrent with another activity (e.g., form for concrete), yet cannot (and need not) be precisely defined as to exactly when they will occur (see Fig. 27).

Other activities must be completed at some uncertain time prior to completion of another activity (e.g., rebar footings before completing form footings in Fig. 27). The computer requires precise relationships and cannot show generalities.

In addition, the time-scale arrow diagram can show assumptions: questions about durations, relationships or activity descriptions, and alternatives that are impossible to show with computer printout. All that is needed is a brief note on the diagram informing readers as to what assumptions have been made, questioning what the relationship should be, or a different type of line (say a dot-dash) to show an alternative path from a decision point or a differing outcome event.

The human eye and brain can grasp the fundamental organization, repetitive patterns, critical path, float, and a sense of the overall criticality and complexity of the entire project and subnetworks from a brief review of a well-prepared time-scale arrow diagram. A similar understanding gleaned from computer printout would take hours of dedicated concentration and elude all but the most determined.

Time-scaling takes longer to draft initially, but once the network is drafted, there is no delay or cost to keypunch data, make the computer run, or wait for printout and debug the data. It also costs much less to update. If a status line is used to show current status instead of redrafting, the cost of monthly or weekly revisions can be negligible compared to computer runs.

More powerful

Finally, the time-scale arrow diagram can permit concurrent consideration of resource availability, space limitations, weather effects, and related activities. If the scheduler rough drafts the schedule in time-scale instead of converting later, all these factors can be considered initially instead of first going through the laborious, expensive and inaccurate process of computer rescheduling, resource leveling, and least-cost expediting. In fact, no existing or contemplated computer system can begin to compete with the sophistication, power, and accuracy of an experienced manager with such a practical tool to aid him in visualizing and analyzing a project.


In summary, CPM and PERT are seldom used or understood in spite of over 20 years availability. In fact, many are strongly opposed to it, having had reams of computer printout and unreasonably detailed, poorly planned CPM schedules forced upon them.

Computer printout alone is not adequate for scheduling. Computer scheduling without an understanding of the basics is largely responsible for CPM’s limited use; it is similar to finding one’s way from a list of streets and intersections instead of from a map.

Computer-generated, time-scale network diagrams, at least the ones seen by this firm, are not yet satisfactory due to the poor quality of graphics. They do, however, hold promise for the future.

Precedence scheduling, although recently quite popular, also is not the answer. If a computer is used, precedence computing is far superior to i-j node computing. In addition, precedence diagramming does have some advantages over arrow diagramming, especially when “roughing out” a very complex network (because it is easy to modify relationships). It doesn’t, however, lend itself to time-scaling, and always must be eventually converted to time-scale arrow diagram.

The most important step to increase the use of CPM scheduling is for everyone to understand it, and to use more judgment when applying it. Whether one uses i-j node or precedence computer computing; non time-scale or time-scale arrow diagramming; precedence diagramming or other methods isn’t as important as properly understanding and using the method selected. The profession must first learn and apply the basics before attempting sophisticated computer technology.

By |January 21st, 2015|Uncategorized|

Schedule Review For Construction Project Owners

Tricks, Traps, and Ploys in Scheduling Claims

Project schedules often go awry. What begins with a realistic plan can quickly snowball into a major dispute. Below are a number of tips to minimize delays and scheduling claims.

Critical Path Schedule
Most project Owners require a CPM (critical path) schedule on large, complex or risky projects. The CPM schedule assures the Owner that the Contractor has a viable plan to complete the project on time. It enables you to track progress to quickly identify delays, provides a blueprint for recovery of lost time, and protects against unwarranted delay and impact claims.

Your first step is a well-written specification, which should require the following:

  • Submittal of electronic schedule files
  • Joint schedule review by the Owner’s representative, and the Contractor’s scheduler and superintendent
  • Monthly schedule updates with narrative reports
  • Daily field reports from the Contractor’s superintendent and all subcontractors
  • Recovery schedules if work falls behind
  • Time impact analyses to justify time extension requests
  • Partial withholding of progress payments for failure to comply

Software Tricks and Traps
By utilizing little-known features of Primavera P3 or Microsoft Project, Contractors can distort the schedule to hide delays or fabricate a claim. More often, CPM concepts or software features are not fully understood, inadvertently creating an inaccurate schedule. You need to know how to recognize these electronic ploys, or bring in professional assistance to find hidden traps.

Action if Delayed
Despite everyone’s best efforts, projects can still experience unforeseen delays. If the delay is the responsibility of the Contractor, Owners should require a recovery schedule. If the Owner causes the delay, insist on a prompt, detailed, joint review of the problem. First, try to re-sequence operations to avoid a delay. If necessary, compare the acceleration cost to the delay cost and choose the optimum solution. Also, take special care when preparing global settlements.

Defense of Scheduling Claims
When a scheduling dispute arises, insist on a detailed time impact analysis, including a comparison of as-planned with as-built. For weather delays, require a comparison to NOAA records. Require submission of all supporting documents (daily reports, timecards, etc.), and a narrative that explains entitlement and how the events or actions by the Owner caused the delays and subsequent costs. To discourage fraud, require certification of all claims.

Through a proactive approach, you can maintain control of your project schedule and adapt to changes without excessive costs. Please contact our office for assistance in reviewing a Contractor’s schedule or improving your own schedule tracking process.

Tips to Avoid Traps
Below are a few tips from our Schedule Review Checklist for project Owners:

  • Out-Of-Sequence Logic: Use the ‘Retained Logic’ option instead of ‘Progress Override’ to avoid invalid progress and delays.
  • Excessive Lag: Lags greater than one week need to be verified and possibly changed to a separate activity.
  • Incorrect Actual Dates: Verify the actual dates. Wrong dates can be used to hide delays or set up for a claim.
  • Multiple Calendars: When analyzing the critical path, unexplained variations in float may be due to multiple calendars.
  • Erroneous Constraints: Check if constraints are invalid or used incorrectly. Constraints can unnecessarily delay the start of critical activities, falsely create another critical path, or cause negative float. Do not use Mandatory Start and Finish constraints, or the ‘Zero Total Float’ constraint.
  • Auto-Cost Rules: Select the ‘Link Remaining Duration and Schedule Percent Complete’ option. If you don’t, separate updating is required that could result in error if one is overlooked.
  • Scheduling Report: Run P3’s Scheduling Report to review constraints, open-ended activities, out-of- sequence logic, and statistics.
  • Check The Data Date: Verify that the report Data Date is correct for the current status.
By |January 21st, 2015|Uncategorized|

Scheduling Best Practices To Avoid Changes, Delays and Claims

For over 30 years, Pinnell Busch has helped our clients reduce claims, resolve disputes, and improve their scheduling and we have developed Best Practices based on our experience. This spring, we surveyed industry practitioners to determine their experiences and recommendations to avoid changes, delays, and claims. We presented the results at the Project Management Institute College of Scheduling Conference in May. The report, a six-page summary, and the raw data are available on our website,

Contract Changes
Project owners and contractors both reported that construction changes averaged 10% of their annual volume of work. Building contractors reported 8%, heavy/highway contractors 10%, and subcontractors 12%. However, individual owners and contractors reported widely varying results:
• Nearly half of owners averaged 5% or less of annual volume.
• Nearly one-fifth reported 15% or more and some reported 50%.

Reason for Variation
The wide variation is due to more than a difference in type of projects and working conditions. It must be due to a difference in procedures and standards. In other words, some organizations do a better job of limiting change than others. More importantly, major improvements are possible through better practices.

Cause of Changes
Both contractors and owners reported scope change as the primary cause of changes. Design errors and differing site conditions were the next most frequent causes, followed by owner delays.

Reducing Changes
Owners have control, or at least influence in the case of design, over 85% of the reasons for change. With better practices, owners can significantly reduce the extent of changes and, therefore, of claims and delays.

We prepared a list of Best Practices to reduce claims, as summarized in the adjacent figure, based on the survey responses and our experience on projects.

The percentage of changes that become claims varies widely – from zero to 50%, with an average of 61⁄2%. The wide variance between individual organizations means that major improvements can be made. There is a strong correlation between a higher percent of changes and more of those changes becoming claims.

Best Practices to reduce claims include: (1) better people skills and attitude/trust, (2) prompt and fair negotiation and payment for changes, (3) fair contract administration, (4) timely notice of change, and (5) clear communication. We strongly recommend partnering as the best overall method to avoid claims and help settle those that do occur.

Most claims (85%) are settled in negotiation with the balance by mediation, arbitration, or litigation. Mediation, however, should always be used before arbitration or litigation to save time, cost and business relationships.

Project ReAlignment, formerly called Intervention Partnering, is a new means of saving troubled projects midway through construction. It ‘wipes the slate clean’ with one change order for all delays and claims to date. Project ReAlignment turns around a troubled project in 30 to 45 days using a small team of experts and in-house staff. The cost savings are enormous and, unlike mediation, based upon documented facts. The ‘bleeding’ is stopped and progress resumes in a positive environment.

Half of all projects are delayed, with over 10% by more than 3 months. The variation between organizations is extreme: one- quarter of building contractors finished 95% of their projects on time, while half were 1 month late on 30% of their projects and 3 months late on 10%. Owners had similar records: 30% of municipal owners’ projects finished on time, but 25% had frequent or severe delays.

The causes of delay mirror the causes of change: scope change, design error, and differing site conditions. Other causes were poor schedules, third party delays, and weather. Most delays are under the owner’s control. Best Practices to reduce delays include those for reducing changes plus: (1) training in critical path scheduling, (2) owners writing better scheduling specifications, (3) contractors preparing better schedules, and (4) owner representatives enforcing the scheduling specifications and tracking of progress more closely.

Scheduling performance by all parties (contractors, owners, and owner representatives) was abysmal.

Owners’ Scheduling Specifications and Enforcement Most owners (60%) were satisfied with their scheduling specifications, but only half required narrative reports which are essential to understanding schedule logic, tracking progress, and identifying pending delays. Only half required electronic schedules, which are needed for independent progress tracking and delay analysis, or contemporaneous time impact analyses to justify delays.

Contractors’ Scheduling Procedures and Results
Most contractors (75%) were satisfied with their scheduling procedures and results – including many of those with frequent and/or severe delays. Owners reported that only one-third of their contractors were good schedulers, one-third were fair, and one-third were poor.

Subcontractors also had a dim view of general contractors’ scheduling practices, which closely matched the owners’ responses. Too few general contractors requested subcontractor input, prepared monthly updates, kept the subs informed, or prepared recovery schedules when delayed. Worst of all, most hid delays and caused trade stacking.

Owner Representatives Scheduling Skills & Practices
Contractors had a very different opinion than owners of owner representative practices. The most serious shortcoming was untimely and unreasonable responses to RFIs and change order proposals, which was also one of the major causes of claims. The survey showed a clear relationship between timely and fair responses and fewer claims.

Best Practices
Our recommended Best Practices include those mentioned above, plus: (1) partnering, (2) achievable schedules, (3) accurate recordkeeping, (4) increased staffing on troubled projects, (5) win/win negotiation and mediation to resolve disputes, (6) training owners and contractors in contract law and scheduling, and (7) more timely submittal of and response to requests for information, notices of change, and change order proposals.

For details, call Steve Pinnell.

By |January 21st, 2015|Uncategorized|

Construction Scheduling Disputes: Proving Entitlement

American Bar Association
The Construction Lawyer – January 1992
By Steven Pinnell


The objectives of a construction project are normally defined in terms of time, cost, and scope — scope being the quantity and quality of the finished product. All are interrelated, such that failure to achieve one objective (e.g., late completion) often results in problems with others (such as costs or reduced quality). All are dependent upon the resources (people) available to accomplish the work and the management and leadership skills of those directing them.

Schedules are a basic element of any project. An understanding of scheduling concepts, and familiarity with techniques of analyzing and explaining construction scheduling problems and their cost impact can be helpful in any type of schedule dispute.

This article provides an overview of current construction scheduling practices and critical path scheduling techniques. It then describes how to analyze a scheduling claim, with specific recommendations on selecting experts and dealing with inadequate data. The next two sections cover preparation and presentation of exhibits, and defense techniques. The final section is a summary. The article also describes a relatively new scheduling technique, “timescale arrow diagramming,” that is more powerful and easier to understand than conventional techniques. It makes an ideal exhibit for scheduling disputes. And it can be used to create an as-built schedule of large, complex projects when the available historical data is inadequate for conventional methods of analysis.

The goal is to explain scheduling concepts and techniques for the litigator and how to manage an expert or the client’s staff in preparing and presenting a scheduling claim. It is as applicable to mediation and negotiation as it is to litigation and arbitration.


Construction Scheduling Practice and Problems

Contract Scheduling Requirements and Enforcement

In construction, as in most industries, “time is of the essence” and a completion date is normally part of the contract. Most contracts do, and all should, require the contractor to submit a schedule of progress and to periodically update it. This helps ensure the project will be completed on time and serves as the basis for resolving any time-related disputes. More specific contract requirements and insistence on compliance are needed, however, to avoid many of the problems currently being experienced. This will also provide better information for conflict resolution or litigation. Attorneys should urge their owner clients to periodically perform a legal and technical review of their standard contract clauses and contract administration procedures.

A Trend Towards More Scheduling Disputes

Historically, the majority of scheduling claims have been by general contractors against the owners of publicly bid projects. However, most construction work is done by subcontractors, 80 percent being common in building construction. Although mediation, partnering and other alternative dispute resolution procedures are tending to reduce construction litigation, the trend is for more scheduling disputes and more disputes between the general contractor and the subcontractors, sub-subcontractors, or material suppliers. This trend is also evident on privately owned, negotiated contracts. All parties are more aware of the cost of delay and impact, are more sophisticated in their scheduling techniques, have tighter budgets that don’t allow for delay or impact, and are more contentious.

How To Avoid Scheduling Problems

The construction industry is rife with poor practices that lead to delays and cost disputes. Owners want to reduce construction time but the designers don’t really know how much time to allow for construction. General contractors seldom prepare a detailed schedule when bidding a project. Subcontractors commit to a fixed price without knowing the time that will be allotted for their work, let alone the working conditions, such as conflicts with other crafts, congestion, or winter weather that can materially affect their cost. Often schedules are prepared without input or commitment from the subcontractors. Or the subcontractor agrees without understanding the schedule or having a comprehensive grasp of the total crew requirements for all of their contracts. And some subcontractors bid more work than they can staff.

During construction, mistakes are found in the plans, unexpected site conditions are encountered, or changes ate made by the owner that delay or impact the work. Failure to promptly order anyone of several thousand different material items can also cause delay. Earlier tasks don’t proceed as quickly as planned, and the work gets pushed into winter weather. Schedules are disrupted and commitments on other projects supersede. Rain and cold cause working conditions to deteriorate; then, in an attempt to finish on time, crew sizes are increased past an efficient level. Prices escalate, efficiency plunges, costs spiral out of control, and you have a schedule-related construction dispute.

At this point, you discover that the original schedule either wasn’t prepared or is incomplete, inaccurate, and has insufficient detail. It may be a bar chart instead of a critical path schedule. Often the owner never approved it. Updates, if prepared, may be sporadic instead of monthly, and usually include only the percent complete as of the report date. If provided, actual start and completion dates are often inaccurate, and no note is made of intermittent progress, insufficient staffing, or the reason for delays.

Most contractors are aware of the above problems, but often need firm guidance from their legal counsel before acting. The recommended course of action is to document good claims management procedures and to train their field personnel in the procedures and basic legal issues.’ This should be a joint effort by legal counsel working with client staff or an experienced construction consultant.

Scheduling Techniques

Bar/Gantt Chart

The most common scheduling technique is the bar chart (also called a Gantt Chart after its developer). Bar charts are easy to prepare and understand, but often lack sufficient detail. More seriously, they fail to show the relationship between tasks (which determines the impact of a delay), and they do not show the critical path (which tells whether a delay to a task will delay completion of the entire project). Nevertheless, they are a good tool for project planning and control, and for demonstrative evidence.

Critical Path Scheduling Methods

Critical path scheduling is a more recent method, having been developed in the late 1950s and normally accomplished with computers. It consists of two steps:

Planning, which identifies each task required to complete the project, the duration of each task, and the relationship between tasks. The technique for planning and the result of this effort is the network diagram. It can be generated on a computer or on paper.

Scheduling, which computes the early start and finish dates of each task based on the project start date. It also computes the late start and finish dates of each task, which are the latest dates the task can start and finish without delaying project completion. The difference between the early start and the late start (or the early finish and the late finish) is the float. Tasks with zero float cannot be delayed without delaying the project, and are said to be “critical”-they are on the critical path. Scheduling is normally done by computer. It can, however, be done manually or graphically on paper.

The two primary methods of critical path scheduling are called CPM (critical path method) and PERT, the latter now seldom used except for the term “PERT Chart” to designate the network diagram. The CPM method itself has two types of diagrams for planning the project:

Arrow Diagrams represent each task as an arrow, with the arrows linked to show relationships between tasks. Arrow diagrams often have numbers in circles at the beginning and end of each activity which identify the activity. The beginning number of each activity is called the “i-node” and the ending number is the “j-node.” The diagram is then called an i-j diagram.

Precedence Diagrams (often called activity-on-node) has the tasks enclosed in boxes with lines between the boxes to show relationships. Each activity is identified by a number. The boxes may also list other information, such as the early start date and duration. The CPM method also has two methods of scheduling (computing start and finish dates and the float):

i-j Scheduling uses the i-j numbers to identify relationships- activities with the same i-node number as another activity’s j-node numbers are successors to that activity.

Precedence Scheduling lists the priors (or successors) of each activity to identify relationships. It also allows overlap (lead) and delay (lag) between the end of one activity and the start of its successor. In addition to the standard finish-to-start relationship between tasks, it allows start-to-finish and finish-to-finish relationships. It is more powerful and easier than i-j scheduling, and will eventually supplant that technique.

Critical path scheduling is a complex subject requiring training and years of experience to master. The essential elements, however, can be explained to a judge or jury in a fraction of an hour by the right expert. This can be crucial to their understanding and to your success.

Timescale Arrow Diagrams

In the early 1970s, this writer developed a method of critical path scheduling called “timescale arrow diagramming.” It combines the timescale of the bar chart with the relationships of a network diagram (Figure I). An arrow diagram is used, because the arrows can be timescaled. The i-j nodes are deleted because computerization is not required and if computerized, the precedence scheduling method is preferred over i-j scheduling. The arrow diagram works well with precedence scheduling.

The result is a flexible, powerful, interactive tool for scheduling and control. It allows the scheduler to “see” the entire project on a single drawing, while simultaneously adding or changing tasks and considering resource constraints, work conflicts, overcrowding, weather impacts, etc. Although somewhat more difficult and time consuming to initially prepare than a conventional non-timescale network diagram, it is a far better product. It doesn’t have to be computerized to determine dates and the critical path, nor be revised in order to level resource demand, resolve work conflicts, reduce overcrowding, or avoid scheduling weather-sensitive work in the winter.

The end product is more usable than a conventional network diagram. Instead of reading two separate diagrams such as some scheduling programs offer (i.e., a bar chart and a non-timescale arrow or precedence diagram) plus a tabular list of dates, you have a single document that displays everything. It is easier to understand because you can glance at a network and identify the critical path (which can be highlighted with color or a heavier line). You can also see that a chain of non-critical activities has only a few days float or several weeks float instead of a specific number.

Although it can be prepared with a computer, the timescale arrow diagram need not be computerized, because you “graphically compute” the start and finish dates of each task and the float is graphically displayed as horizontal relationship lines. It is normally prepared on grid paper to aid in laying out the diagram. Other suggestions to aid in preparation of a timescale arrow diagram are described in various professional and trade journals.

Some computer scheduling programs can generate “connected bar charts” that have many of the features of a timescale arrow diagram. Few programs can condense a major project on a single sheet that is as readable and useful for exhibits as Figure I. This identifies the major project phases with large text adjacent to each subnetwork and with summary activities (hammocks) at the top of the drawing. The critical path is clearly identified by the heavier line and the float shows as horizontal dashed lines.

Computer Scheduling

There is excessive reliance on computers for scheduling. Too many contractors believe all they need to schedule a project is to buy a project management (scheduling) program. They fail to understand important scheduling concepts or to provide adequate management input and control. The result is an inaccurate schedule, having insufficient detail, which isn’t really used to manage the project. Often, it merely fulfills the contract scheduling requirements and the superintendent plans the job on short-interval bar charts that bear little relationship to the approved schedule.

The courts also have a tendency to place too much credence on computer analysis because they sometimes fail to weigh the accuracy and completeness of the underlying data. Computer analysis is therefore mandatory in order to ensure the credibility of your analysis. Critical path scheduling computations involve simple addition and subtraction. There is nothing the computer does that a skilled individual cannot do better-except for processing the great quantities of data that must be searched, sorted, and summarized.

The “Art” of Scheduling

Often overlooked is the fact that schedules are but “estimates” of what can and will be done. They can vary widely in accuracy depending upon the skill and project knowledge of the individual preparing them, the complexity and determinability of the project, and the level of scheduling effort expended. More importantly, they are subject to the degree of commitment made by the individuals or groups that will accomplish each task and to the persistence and efforts by the individual assigned to manage the project.

A “good” schedule is one that can be accomplished with the resources available within the allotted time and at reasonable cost. There are numerous variations that would also suffice.

Legal Issues

For information on legal issues, consult current case law as published or presented at construction law seminars. The article by Wickwire, Hurlbut, and Lerman, ”The Use of Critical Path Method Techniques in Contract Claims: Issues and Developments, 1974-1988″ is a good starting point.


Selecting An Expert Witness

Decisions on demonstrative evidence are very much secondary to your selection of experts. Not only does the quality of experts vary widely but also their approach and preferred type of exhibit will differ. An “old hand” with years of experience may be comfortable only with bar charts. Most construction claims consultants, however, use computerized scheduling techniques. The courts favor critical path methods in determining the impact of delays or acceleration. In fact, it is very difficult to “prove” schedule impact without a critical path schedule. If using bar charts for demonstrative evidence, a computerized critical path schedule should be prepared to validate the bar chart.

Experts in schedule disputes must be experts in the industry. Don’t use a theorist or a computer consultant to analyze construction, although computer skills are almost mandatory. The expert must know construction methods, construction industry practice, the fundamentals of contract law and current case law related to construction, and even engineering/architectural design practices and standards. Experience as an arbitrator is helpful. The expert should have extensive field experience to better appreciate the impact of winter weather, overcrowding, constant change, acceleration, and other factors affecting morale and productivity.

The personality of the expert is also important. Some are good at research and painstaking analysis, but don’t come across very well under cross-examination. Others are very convincing as a witness and do well on broader issues, but are not well enough organized or efficient to turn loose on major investigations. Sometimes, a team approach using two individuals with complimentary skills and personalities works best. In any case, you need to establish a clear-cut scope of work, with budgets and schedules for each phase.

In some cases, the client has expertise in critical path scheduling and you will need an expert only for an independent verification of their work. Your client may know credible experts in construction methods and scheduling. If not, ask the Associated General Contractors, Associated Builders and Contractors, or other attorneys.

If your expert (or opposing party’s expert) has published any papers, read them. When selecting an expert you should verify their experience, including litigation or arbitration, and obtain references on past testimony and the results. If dispute resolution is possible, it is best if your expert is known and respected by the other party and has a reputation for fairness.

Data Collection and Review

Early Involvement of Your Expert

It is important for your expert to be involved in discovery and depositions. Not infrequently, important documents are missed or misinterpreted and pertinent areas of inquiry are left unexplored because of insufficient construction expertise at this phase.

You should not rely solely upon your client’s advice; it is this writer’s experience that nearly every construction claim as presented by a client misses major issues (such as concurrent delay) that vitally affect the dispute. In some cases, the initial thrust of the claim has been discarded and other issues of more important and greater cost impact substituted. Clients (either contractors, designers or owners) seldom have the breadth of experience in claims analysis and scheduling or the familiarity with construction law needed to identify all those items that are important. Their involvement in the project often makes them blind to their company’s shortcomings.

If construction is still underway, the expert can gather additional information, or even help mitigate damages. You should ensure that notice provisions and other legal issues have been addressed. Your expert can check recordkeeping and job management procedures. If scheduling is done by onsite personnel, an independent review is recommended. The expert’s fees for rescheduling required by a delay can be compensable as part of the change order.

For suggestions on retaining and managing experts, see Marted and Poretti’s article in The Construction Lawyer.

Organization of the Client’s Data for Review

When organizing data for expert review, have your client organize its files, put correspondence in chronological order, and otherwise make it easier to review all the documents and to ensure they are complete. Too frequently, individuals within the client’s organization fail to inform an expert of additional information that is available. Oral or written briefings and a written narrative of the dispute and tentative legal theories are also helpful in getting up to speed at a minimum cost.

The most critical documents to be identified for a scheduling claim are the original (as-planned) schedule and the periodic updates, as well as any draft schedules prepared but not submitted. These show the original plan and what actually happened. The final update often can be used as the as-built schedule.

Documents needed to supplement the schedules include correspondence, daily diaries, inspection reports, foremen’s and superintendent’s reports, submittal logs, photographs, weekly labor cost reports, certified payroll reports, timesheets (especially if annotated), test reports (which, for example, provide the dates of concrete pours), progress payment requests, submittal logs, shop drawings, and even delivery tickets. Other items include the contract documents (with all modifications), subcontracts and purchase orders, requests for information (RFIs), change order proposals and notice of claims, approved change orders, and minutes of meetings.

Discovery and Depositions

If all documents will not be copied, your expert should assist client staff and paralegals with discovery, in order to identify those few critical documents that are too obscure for a non-expert to recognize as important. For example, penciled notations by the reviewing architect/ engineer on the file copy of shop drawings may be crucial to proving or defending claims for slow review or unreasonable rejection of substitutions. The expert must be briefed and conduct an initial review before discovery, in order to know what might be important. The expert can also prepare suggestions for deposition questions. This may resolve issues not clearly documented or help determine their defense to anticipated legal strategies.

Site Visit and Interviews

If warranted, the expert should visit the job site (especially if work is still progressing) and interview job personnel. Failure to do so can result in a lesser grasp of the project and loss of credibility during cross-examination.

Analysis of the Data

Objectives, Legal Strategy and Work Plan

Before starting analysis, identify the objectives and tentative legal strategies. You should require an agreement on the scope of the expert’s investigation and analysis, the time required, and budget. For schedule-related claims, the objectives usually include finding and/or creating the following:

• As-Planned Schedule
• As-Built Schedule
• Comparison and Analysis of Differences
• Determination of Cause and Effect
• Would-Have-Been, But For … Schedule
• Comparison and Analysis of Differences
• Computation of Damages

A detailed work plan for the investigation, and all other aspects of the litigation, will help ensure accomplishing all objectives while maintaining the schedule and budget. The work plan should be in the form of a bar chart or network diagram and be “resource loaded” with the estimated expenses and effort by each individual. This will generate the budget and can be used to track and control the work.

Problems Often Encountered with the Data

Construction disputes often involve mountains of conflicting, fragmentary evidence. Memories may be vague, incorrect, or self-serving. Correspondence may be of limited value-beyond proof of notice, intent, and when the parties were aware of an event-due to the posturing of most parties in a dispute. It cannot be relied upon, even for the accuracy of stated dates. Original schedules are often incomplete, with insufficient detail, or simply incorrect. Schedule updates are often not prepared, and if existing usually contain only the percent complete of each task as of the update date.

Daily diaries may fail to include important information, or may not consistently record it. The accounting records seldom identify the extra costs of impacts, or fail to separate impacted work from non-impacted work, and the timesheets upon which they are based are often too numerous to review. Too frequently cost records fail to note the quantity of work accomplished each period so that separate productivity rates can be established for impacted versus unimpacted work. Photographs, if made, often lack dates and never include a clear explanation of what is happening. In short, it is very difficult to determine what actually happened, let alone the impact of those events and their costs.

Computerization of Historical Data

Laptop computers and improved software have changed data collection and analysis dramatically. One can abstract critical documents and index each record of the database to a source document, to multiple claims or other topics, to a date, and to an activity number on the as-planned schedule. This can be accomplished during the initial document review, if the expert assists in discovery. If available, electronically stored data can be imported to the database without retyping.

The computerized database can be sorted by topic and then in chronological order for review. This facilitates understanding each topic and the overall project, and ensures that no issues are overlooked. References to the source documents and proper organization of those documents (chronological by type) will permit more detailed review later and provide an “audit trail” if statement is challenged. If a written report is needed, the researcher’s database will provide the basis of that report, and the narrative portion of the report can include as many references as necessary to substantiate each event and its impact.

Issue Analysis and Working Papers

The expert will often be asked to analyze specific issues, such as possible concurrent delay by the contractor, industry practice, the expert’s interpretation of critical clauses in the specifications, etc. These analysis and factual investigations of key events are usually accomplished as discrete tasks. They define the issue, assemble and analyze the material available, identify items needing further effort and reach a conclusion with recommendations. As long as they can be preserved from discovery as attorney work products, issue analyses are best done in written form because they can be shared by all individuals of the dispute resolution/litigation team. This helps ensure that everyone is aware of and understands the key issues. Unlike a verbal briefing, they can be referred to later and refresh memories.

Working papers should be prepared on a word processor or a spreadsheet, so that information from the historical database and schedules can be readily incorporated. Easy transfer of data between various programs is essential for economical analysis.

Written Reports

Written reports are often needed to explain complex issues to the dispute resolution/litigation team, and in some cases may be provided to the opposing party and fact finder. They can present a chronology of the project, a narrative to accompany the schedules and establish entitlement, and the cost data and computations to prove damages. If issue analyses have been documented and are pertinent, they should be incorporated into the report. Reports should be prepared for counsel, instead of directly for the client, to limit the ability of the opposing side to obtain them during discovery.

Written reports, if requested, should be heavily referenced to source documents or noted as the opinion of an expert or a comment by an individual involved on the project. If available, the opposing party’s records should be referenced in preference to your client’s records, because they are less likely to be contested. There should be an “audit trail” from every conclusion back to detailed facts in the body of the report and from each fact to one or more source documents. References can be in square brackets; as an example [L-COE/GC 14Jun91] would be a letter from the Corps of Engineers to the General Contractor dated June 14, 1991 and [J] would be based on the judgment of the author and the preceding text. If the source documents are organized by type (i.e., letter telephone conversation, submittal, etc.) and sorted chronologically within each type, location of a referenced document is quite easy.

Issues not yet fully resolved, notes, and questions for reviewers in draft documents can be placed in different brackets ( ) to facilitate global editing after resolution.

“As-Planned” and “As-Built” Schedules

There should be a detailed and accurate as-planned schedule. If not, it will need to be reconstructed-based on whatever data is available. If the as-planned schedule is a bar chart, it can be converted into a timescale arrow diagram-either by drawing relationship lines between the bars or by computerizing and adding relationships. Obvious, minor errors can also be corrected.

Computerization of a hand-drawn “As-Planned” schedule is usually recommended, to aid in analysis and comparisons. Most claim consultants prefer a specific scheduling software program; if the as-planned schedule was generated with a different program, it is easy to generate an ASCII file (by sending reports to a disk file), which can be imported to the preferred program. The better scheduling programs can import several different data formats and all the major programs claim to comply with the Corps of Engineers’ NAS Data Exchange format (ER 1-1-11, March 15, 1990) for transfer of scheduling data between different programs.

The final schedule update constitutes an as-built schedule (except for the work remaining in the final work period). Unfortunately, updates are sometimes inaccurate, incomplete, or nonexistent. One should always validate the schedule updates, and expand the level of detail to aid in creating the “Would-have-Been, But For …” schedule.

Creating an As-Built Schedule If Incomplete Data

Three Alternatives

Sometimes the data provided is not adequate for a normal investigation and determination of the facts-at a reasonable cost and some certainty. Then you and your client need to decide whether to pursue a “total cost” approach, rely on an expert’s “judgment,” or commit the time and money to reconstruct the project with a “detailed as-built schedule.”

The total cost approach to construction claims is to present the actual cost of the work, subtract the estimated cost as bid, and ask for the difference as damages. Much has been written about this approach, and the difficulty of having it accepted in court. It is not generally recommended.

The standard alternative to a total cost approach is to put together the best analysis possible using conventional procedures based on the client’s allegations or an expert’s opinion. This requires expert judgment based on years of experience, and involves many assumptions and a lot of uncertainty. It is not difficult to prepare and is reasonably economical. In court, however, it often becomes a contest of whether your expert or the other side’s expert comes across as more credible. See “Conventional Methods of Delay and Impact Analysis,” infra.

An alternative to either an expert’s “judgment” or a total cost claim is an integrated, multi-document analysis that reconstructs the project on a day-by-day basis. This synthesizes numerous source documents (accounting records, timesheets, daily diaries, correspondence), each of which is incomplete for purposes of determining the events that happened and their consequence, into a coherent single document that describes what happened and why. This requires a format that can accept thousands of separate notes with references to individual source documents, brief narrative statements describing what happened and why, tabular information such as daily rainfall and crew sizes, graphical information such as a resource histogram or a percent complete curve, and some form of network diagram that displays the data in a readily understood manner.

The best format is a timescale arrow diagram, although a spreadsheet with notes can be used in simpler cases. Narrative reports or working papers are inadequate for organizing the data so that it can be understood.

Creation of a “Detailed As-Built” Schedule

A Detailed As-Built Timescale Arrow Diagram of a construction project starts with a large sheet of paper (up to 3 feet by 5 feet with a grid pattern to help in organization (Clearprint® paper is recommended). A calendar is placed across the top of the drawing with one or more grid squares for each day of work. The layout of the schedule is more like a modified bar chart rather than a network diagram.

Using the “As-Planned” schedule as a guide, each daily actual event from the source documents is recorded on the paper to form the “As-Built” schedule. Brief comments are made as needed. If necessary, individual one-day events forming a task are coded (e.g., the letter “p” above the line to signify a concrete pour and “r” for rebar as part of a “construct footing” activity) and referenced below the line with a code for the source document (e.g., “FDR” for foreman’s daily report). Crew sizes for each cost code or task can be printed across the bottom of the drawing in a matrix format to aid in identifying the start and finish of each task, periods of inactivity, and levels of effort. Each task on the detailed as-built timescale arrow diagram is built a day at a time until the start and finish dates are established for each, along with any periods of inactivity. Sequential tasks are then linked by arrows to show the flow of work. Judgment must be applied to fill in the blanks and to connect dependent tasks.

Creating a detailed as-built schedule can be very difficult. Activities are often intermittent, with varying (and often inadequate) crew size, which should be identified. The as-planned logic is often incorrect and grossly simplified as the actual relationships of tasks are very complex. Tasks often overlap and frequently are performed in a seemingly random order based on the manager’s preference or perceived efficiency.

The actual start and finish dates may be difficult to determine precisely. Should they, for example, include a subcontractor’s mobilization, material delivery and layout, or repair and rework; or should those be separate tasks?

The reliability of source documents cannot be assumed. Basic business records maintained by field personnel (foremen, superintendents, and inspectors), such as timecards and daily diaries, are generally more reliable than records maintained by jobsite managers or the home office. With experience, one can judge the veracity and accuracy of an individual’s records from cross-checks with other records, comments by the author, and even the “tone” of the text.

Inconsistencies and conflicts may create questions that cannot be fully resolved. On one project, the backside of a number of daily reports copied during discovery were stapled to the wrong front sheet, which took considerable time to identify and correct. Client-prepared data sometimes contains small errors that may preclude full reliance without some verification. Recording of facts must be without error in order to avoid inconsistencies during analysis or possible exclusion as an exhibit.

The result of the investigation is a very detailed document, often containing thousands of individual events with references. It becomes a secondary source document and can be referenced by a written report or in testimony. If challenged, each element can be traced to an original source document or to the expert’s judgment.

Even when the documentation is grossly inadequate, a detailed timescale arrow diagram can be useful, as a large number of small judgments are more reliable and more credible than a few gross assumptions by a hastily briefed expert.

The primary problems with this approach are the cost and time to prepare, plus the difficulty in finding someone with the experience and skills needed to perform the analysis.

Costs can be reduced by focusing on critical issues. For example, on a recent claim analysis, a detailed as-built was prepared only for the first 60 days, which was the most important period, and the as-built information from the monthly updates was used for the balance of the “As-Built” schedule.

Conversion to a “Condensed As-Built” Schedule

The next step is to condense the detailed as-built schedule into a more understandable form for computerization and further analysis. Depending upon the complexity and completeness of the detailed as-built diagram, this may require the use of clear acetate and colored pens to define the tasks and flow of work. The result is the condensed as-built schedule (timescaled) which can be plotted by a computer program (similar to Figure I).

The condensed as-built schedule defines the actual progress and flow of work, and will be compared to the as-planned schedule. It should, therefore, have the same activities and the same general layout on the network diagram, whenever possible. Normally, it has more activities than the as-planned schedule-for unanticipated tasks, added work, and impact activities. It may have intermittent progress of some tasks due to inclement weather, contract delays, or insufficient personnel. It should be annotated to highlight delays, acceleration, impact, and the events that caused them. It should also show the original completion date, the revised completion with approved changes, the actual substantial completion, and the final completion date. A narrative of all assumptions and judgments made with condensing the detailed as-built can be associated with each task.

Creation of the condensed as-built schedule can be quite difficult, especially in establishing the relationships between tasks. This often requires considerable experience and judgment, in addition to careful review of the as-planned schedule and the actual logic of the work. The physical effort, however, is relatively easy as you simply copy the computerized as-planned schedule and edit it for differences in duration, logic, and additional activities.

The Cost of Preparing a Detailed Schedule Analysis

Preparation of a detailed as-built schedule can be expensive, with the cost varying widely depending upon the quality of the available data and the size and complexity of the project. For example, the basic claim analysis to defend a transit agency from a fiercely contested $250,000 suit on a $900,000 public works project cost $5,000, and a detailed as-built schedule to confirm the initial conclusions cost about $10,000. Other analysis, preparation of exhibits and four days of testimony and cross-examination cost substantially more-but our client was awarded $130,000 for contractor delays and attorney’s fees. A smaller example is a project review, analysis of multiple disputes, preparation of an as-built schedule (not detailed), and a preliminary estimate of delay and impact costs on a $400,000 building remodel for purposes of negotiation. The cost was under $5,000. An expensive example is the detailed as-built schedule for a $20 million advanced wastewater treatment plant that cost nearly $50,000 due to grossly insufficient, conflicting records and a very complex project. Typically the cost for such a project would be $15,000 to $30,000 less if the records are good.

The cost of claim preparation or analysis must be proportional to the benefit expected. The additional cost of a detailed as-built schedule and a more thorough would-have-been schedule and damage computations must be balanced against the likelihood of a more favorable award. A compromise using the detailed as-built schedule for critical periods and more traditional analysis for the balance of the project may provide a satisfactory product at substantially less cost. In any case, you should require a reasonably detailed work plan from your experts and establish clearly defined budgets and schedules for each phase of their work.

The most effective means to reducing the cost of a claims analysis is to keep good records.

Fixed-price agreements are not recommended for claims analysis because the effort required is difficult to estimate in advance and may change as the analysis proceeds. Time and material agreements with a not-to-exceed budget for each phase (unless authorized) are recommended. Be prepared for changes as the analysis proceeds.

The “Would-Have-Been, But For …” Schedule

Determining what happened is only the first step. Next, the events that are due to actions or inactions of the other party or are otherwise reason for a time extension and/or compensation must be linked to their impacts and from there to a scenario of what would have happened absent the identified events. One method of doing this is to compare the as-built schedule to the as-planned schedule and determine why they are different. The events that are the responsibility of the other party can be identified and analyzed for their impact and whether the damages and resulting delays are compensable. Concurrent delay by the contractor, if any, must be addressed as it will preclude award of delay damages. Non-excusable delay by the contractor or better-than-expected progress should also be identified.

A bar chart is usually best for comparison of plan to actual and the scheduling program can quickly generate such charts (Figure 3). Relationships between tasks can be displayed with some software, although showing all relationships may make the drawing too confusing. Overlaying cumulative curves of work accomplished (and/or effort expended) and histograms of planned and actual resource use (labor and equipment) on the bar chart can be useful in analyzing the data, especially when the events causing the impact are plotted on the diagram. Tabular comparisons are also needed and some scheduling programs have special features for such analysis.

The as-planned and as-built schedules, supporting computations, and previously-generated database and issue analyses will be used to create the would-have-been schedule, and all should be documented with a narrative for each task. In some cases, schedule simulation and other computerized techniques beyond the scope of this paper will be used to qualify the delays and their cost impact.

The result is the “Would-Have-Been, But For …” schedule that identifies what would have happened absent the events that are the responsibility of the other party or that are non-compensable reasons for time extension. It should be in the same format (timescale arrow diagram), the same level of detail, and generally have the same activities as the “As-Planned” and “Condensed As-Built” schedules. This is where experts truly earn their fee. Again, the physical effort is fairly easy as either the computerized as-planned or the condensed as-built schedule is copied and edited.

Some experts start with the as-built schedule and subtract the claimed impact events to generate the would-have-been schedule. This writer generally prefers to build the would-have-been schedule a step at a time from the beginning. One must analyze what “would have” happened at the time a specific event occurred, based on the intent and knowledge of the jobsite management at the time, instead of what “could have been.” This is where correspondence can be very helpful, although the as-planned schedule is more important than any other document to establish intent.

Activities on the would-have-been schedule that would be accomplished under different conditions than the as-built must have their durations adjusted appropriately. This doesn’t mean just using the as-planned schedule durations, but may require a comparison of similar activities accomplished in unimpacted conditions. In some cases this may require a detailed analysis of the activity (the author once spent three weeks analyzing the critical piledriving activity on a large South American harbour project, which controlled the duration of the entire contract). The results, however, can be significant; on one recent project such an analysis determined that a twelve-day delay to a six-month project increased the cost by nearly 50 percent. This became understandable when the analysis revealed that those twelve days represented 42 percent of the available time to do the weather-sensitive earthwork before the winter rains began.

Comparison of the “As-Built” to the “Would-Have-Been, But For …” schedule will determine the allowable time extension and thus entitlement. The time extension may be partly compensable and partly non-compensable.

Other Analysis Methods and Issues

Other Techniques and Issues

Fragnets are portions of a network that are displayed separately for easier analysis and understanding. They are extremely useful for both analysis and exhibits.

Cumulative curves of percent complete or cash flow and histograms of planned and actual resource use are sometimes useful for analyzing impacts from delays, impact and acceleration. They can be easily generated for each version of the computerized schedule by cost-loading and resource-loading each task. In addition, a narrative should be written for all schedules (as-planned, as-built, and would-have-been) documenting the assumptions and expectations.

CAD drawings, or at least colored drawings or colored acetate overlays, can be helpful in identifying and analyzing what areas were impacted. Photographs and videos can also aid analysis. In addition to verifying statements in the other documents they can provide a great deal of additional information. For example, rock stockpile quantities can be computed by horizontal scaling from objects with known dimensions and the angle of repose for the specific material. A powerful, well-lit magnifying glass will help identify details.

When analyzing delays, it is important to identify mitigation efforts and the cost of acceleration to avoid further delays. These costs should be compensable.

The analysis should also investigate possible and alleged concurrence to ensure that contractor-caused delays were not concurrent with owner delays so as to prevent compensation for delay costs. In many cases, contractors will slack off on some near-critical activities in order to minimize costs, which can lead to allegations of concurrent delay.

There are other techniques available and issues applicable to specific projects; which are beyond the scope of this document. Your expert can identify which are relevant.

Conventional Methods of Delay and Impact Analysis

More conventional methods of schedule analysis are:

Global Impact or “Total Delay” Approach. This is a simplistic and usually inaccurate method of showing delay, acceleration and impact-similar to the “Total Cost” approach of computing damages. It plots the as-planned and as-built schedule and sometimes the would-have-been schedule as either single bars or highly summarized bar charts, and alleges the differences to be the fault of the owner. No attempt is made to show possible contractor error or concurrent delay, or to show the logic of cause and effect on the overall project. At best, a list or descriptions of the alleged delays will be presented to substantiate the claim. It is a satisfactory method only when used to summarize the results of more detailed analysis.

Net Impact Approach. This attempts to deal with concurrence by displaying only the net effect of claimed delay. It displays the as-planned and as-built schedules as either single bars or summary bar charts and shows the period of each alleged delay either separately or embedded in the as-built schedule. Often, the entire period of a change order from issuance to completion of the work is shown as a delay to the overall project. The total sum of all the delays is either considered irrelevant or alleged as proof of constructive acceleration in order to achieve the as-built completion date.

One-Sided “But-For” Approach. This inserts into the as-planned schedule the admitted delays of the party preparing the document (usually a far smaller number than warranted) and alleges that all other delays are the fault of the other party. In addition to being a one-sided approach with seriously understated impacts from the admitted delays, it also makes no adjustment for circumstances and the schedule status at the time the event occurred. Nor does it provide an adequate connection between the alleged cause and its effect.

Adjusted As-Built Approach. This often uses a critical path network of the as-built schedule and inserts alleged delays as distinct activities restraining the project. It is similar to the “Net Impact” approach, except that it alleges to use critical path analysis.

Time Impact Analysis Approach. This describes an iterative process of multiple analyses, starting with the as-planned schedule which is adjusted each time an impacting event occurs. It is far superior to the methods described above, and is similar to this author’s approach as described in “The ‘Would-Have-Been, But For …’ Schedule,” supra.

Verification of the Analysis

The analysis should be verified by reviewing it (or at least discussing key points) with client personnel and subcontractors. It is difficult to defend a position when your client’s staff and subcontractors don’t agree with it.

You should also either get a signed agreement from the subcontractors that the claim fully represents their damages, or exclude subcontractor claims from your settlement.

Computation of Damages

All the work done to this point will lead to naught, unless you can now prove damages — a specific, reasonably accurate dollar amount. This may be the most difficult task facing the expert, and one that often relies on professional judgment as much as on quantification and analysis.

A full review of the methods and techniques for computing damages is beyond the scope of this document; they are amply described elsewhere.

Preparation and Presentation of Exhibits

Whereas the expert normally has considerable leeway in the claim analysis, within the defined scope and budget, the trial lawyer needs to exercise close control of exhibit preparation and has total control of the presentation.

The essential requirement in the presentation of schedule-related claims is that it be as simple and straightforward as possible. It is therefore best to limit the number of exhibits or to only briefly review the detailed exhibits and focus on the summaries, because too many exhibits can dilute the overall impact of the presentation.

We recommend that detailed information be presented only to the extent necessary to build a foundation, to establish credibility in the mind of the fact finder, and to intimidate the opposing side with the thoroughness of your preparation. The presentation should focus on summaries of the schedules and damages, with specific details only when warranted.

Summary of Exhibits

Exhibits for a construction scheduling dispute will normally include the following and be introduced in the same general order:

Overview of the Claim and how it will be proven, so that the fact finder knows what to expect.

As-Planned Schedule that identifies what the contractor expected to do when starting the project.

As-Built Schedule that describes what actually happened.

Comparison Schedule of the “As-Planned” to the “As-Built” schedule with an analysis of what caused the differences.

“Would-Have-Been, But For …” Schedule that describes what would have happened absent the actions of the other party.

Comparison Schedule of the “As-Built” to the “Would-Have-Been” schedule and analysis of the differences and who is responsible. It proves entitlement.

“Fragnets” of critical portions of the schedule that focus on the activities impacted for each issue analyzed.

Other Exhibits demonstrating specific issues. These may include percent-complete curves, resource histograms, pie charts and photographs.

Cost Data to prove damages.

Summary Chart or Table recapping the presentation and focusing attention on the key issues.

Network Diagram Exhibits

Original As-Planned Schedule and Updates

If an as-planned schedule and updates were submitted by the contractor to the owner or designer, they should normally be included as exhibits, in order to establish the validity of subsequent exhibits. It is helpful to have them blown up to be approximately the same size as the other schedule exhibits. Acetate overlays with colored relationship lines and other information can be used to explain job logic.

Modified and Redisplayed As-Planned Schedule

The original as-planned schedule often has some obvious errors. These can be corrected and the modified as-planned schedule can be displayed as a timescale arrow diagram. If the original as-planned schedule was a bar chart, relationships can be added. Conversion to a timescale arrow diagram makes it much easier to follow the logic and understand what was planned. To aid in understanding, the tasks should be grouped in subnetworks and labeled (as in Figure 1), and a summary as-planned schedule should be prepared for easy explanation of the initial plan when the project started. The presentation of the summary as-planned schedule can be made concurrently with presentation of the site/phasing plan described in “Site and Phasing Plans,”infra.

Detailed As-Built Schedule

If an accurate, as-built schedule was prepared during the course of the project, that document can be displayed as the as-built schedule. Frequently that has not been done and a detailed as-built schedule must be prepared, as described in “Creating an As-Built Schedule If Incomplete Data,” above (Figure 2).

The detailed as-built schedule is presented to validate the condensed as-built schedule. A clear acetate overlay with felt-tip pen coloring of the activities can be used to link the two together.

Condensed As-Built Schedule

This is the computerized version of what actually happened, which condenses the thousands of references on the detailed as-built to the same general level of detail as the as-planned schedule. It normally has more tasks than the as-planned schedule, with the same layout and activity descriptions where possible. If the exhibits are used for in-depth study by the fact finder, the condensed as-built schedule may become the key document for explaining what happened.

The presentation of the condensed as-built schedule must build from the detailed as-built schedule, in terms of what happened. It isn’t necessary to explain each task or even the overall chronology, but only to demonstrate the thoroughness of your analysis. The testimony can then focus on the summary as-built schedule, as it can be easily understood-which is essential to explaining what happened to the fact finder.

Summary As-Built Schedule

For easy comprehension by a fact finder, a higher level of summary (with at most thirty to forty tasks), with graphical highlighting of key events (milestones) and narrative text, will be needed. This diagram should have the same layout and the same scale as the condensed as-built schedule, and should use color to highlight and simplify the logic. It may also include superimposed resource histograms (Figure 2) and percent-complete curves. It can be presented in a modified timescale arrow diagram format, similar to a bar chart. Some scheduling programs can generate this type of chart automatically, through a “roll-up” feature.

You now have a complete, auditable trail from thousands of individual source document references to a clearly understandable exhibit that summarizes what happened and demonstrates the time impact on the project.

“Would-Have-Been, But For …” Schedules

There will often be two “Would-Have-Been” schedules- one with the same level of detail as the condensed as-built and one at a summary level. They should have the same general layout as the other schedules, and must be based on the as-planned schedule, as modified by the events chronicled by the as-built schedule. They cannot be just “could-have-been” schedules, but must represent the most likely course of action absent the claimed event(s).

Presentation of the “Would-Have-Been” schedule and its acceptance by the fact finder is crucial, as this is where you prove entitlement. All questions and doubts should be resolved at this time, before proceeding to damages.

Comparison Schedules

After each of the schedules has been presented (as-planned, as-built, and would-have-been), they can be compared to show how the project changed and how it would have been absent the disputed events. Color is best to show the work and to differentiate between the two schedules being compared, but hatching can be used if necessary. Schedule comparisons are best done with bar charts (Figure 3).

Fragnet Schedules

Fragnet schedules are portions of a network diagram, showing only the pertinent portions for easier analysis and understanding. They should be extracted from the full network, blown up in size and displayed as separate exhibits explaining specific events and issues. Some software can do this automatically.

Cumulative (Percent Complete) Curves

Cumulative curves are frequently used to show progress (percent complete, cash flow, and earned value), and to compare planned with actual progress. An abrupt change in slope of the curve (e.g., a flatter slope, indicating slower progress) coinciding with an event (i.e., an alleged cause of delay) and a steepening when the issue is resolved, supports the contention that the event caused the change.

Cumulative curves can overlay a summary schedule to graphically illustrate the pace of construction. The as-built curve can be compared to the as-planned or would-have-been curves to illustrate the differences.

Rainfall is normally displayed with a histogram, which underemphasizes the impact of winter rains. An alternative is to use a cumulative curve, with the increased slope in winter clearly illustrating the onset of the rainy season. Starting with a base of zero in early summer will further emphasize the cumulative impact of winter rains after the limited rainfall of summer.

Histograms (Periodic Curves)

Histograms (periodic curves) are most frequently used to show planned and actual resource use (i.e., the number of workers). The planned staffing of a project with a steady increase of crew size followed by a constant crew size and then a slow decline to project completion can be compared to the impacted schedule with lower initial staffing during good weather, excessive peaks during inclement weather, and wildly fluctuating levels through to completion. This is especially effective if the start and finish of the impact are plotted on the diagram and correspond to reduced staffing and then excess staffing to make up for lost time.

Histograms (of resource use or rainfall) can be overlaid on a summary schedule and combined with a cumulative curve (of progress) to explain what happened.

Tabular Schedule Reports

Tabular data are needed to support the testimony and other exhibits and are used extensively in claim documents or written reports. It should seldom be used as demonstrative evidence except to lay a foundation, as it requires careful study and expert knowledge to understand. Presentation of specific dates or tabular data is best done in conjunction with graphics, as in Figure 3.

Other Types of Exhibits

Cost Data

Cost data are normally in tabular form and presented in a spreadsheet. Where possible, graphical representation of costs will aid in understanding. For example, variations in productivity rates (cost or labor hours per unit of output) can be plotted on a vertical scale as a line drawing for each reporting period. The learning curve effect of increased efficiency with experience will be apparent, as will abrupt changes at the beginning and end of the period of impact.


Photographs can be very helpful in providing an understanding of what happened on a project and in demonstrating impact conditions that result in extra costs. Photographs of mud, rain, snow, crowded conditions, etc. can generate a feeling for the problems experienced. They need to be organized either chronologically or grouped by claim or topic, with the date on each photograph and a description of what is happening and where it is.

For inclusion in a report or for individual review, 3″ X 5″ prints give adequate definition. Four can be pasted on 8 ½ ” X 11″ paper with a brief description for color copying at less than one dollar per page. Aerial photographs (which in some areas can be obtained for around $200 per flight if ordered monthly) and other items needing more definition can be printed at 8″ X 10″ and pasted onto 8 ½ ” X 11″ paper for inclusion in a report. For courtroom exhibits, larger blowups may be used. Photographs can be used to supplement a verbal description of conditions in order to give a better understanding of actual conditions. Selective presentation of photographs can give a distorted view of conditions. To correct the problem if used by the other party, you can show a more representative series of photographs or photos of work either progressing or not during the impacted period.


Video cameras are easy to use, small enough to carry around a jobsite, and economical. Many project owners and contractors are using videos to document problems or the general course of construction. If available, videos of the project can be extremely helpful. A few minutes of film illustrating impact and difficult working conditions can be extremely effective in convincing jurors of the general extent of damages (sometimes out of proportion to the actual impact). Careful editing and a clear narrative can focus attention on important elements. In some cases, “freezing” selected views or insertion of text and simulation of events can help the presentation. If only selected material is presented, all film must be made available to the opposing party in unedited form.

Time-lapse Photography

This condenses a full day’s progress into a few minutes to provide a quick review of daily progress. It also makes work patterns and inefficiencies obvious to non-experts, and can be analyzed by a time-and-motion study expert to determine productivity rates and impacts.

Pie Charts

Pie charts can be used to display costs, resource use or other numerical information. They help focus attention on differences between cost elements and the relative distribution of costs, or resource use.

Site and Phasing Plans

A simplified plan of the overall project, with boldly lettered descriptions of each work area or where specific claims occurred, can be helpful in understanding the project and should be referred to frequently during testimony. Large bold text, hatching and half-tones, or color can be used to show project phasing. In some cases, colored acetate overlays can be used to show project phasing.


Detailed drawings are very helpful in explaining specifics .of the project, especially if color-coded for easier understanding. This can be done directly on copies of the drawing and blown up if needed, or on acetate overlays to show various conditions. More sophisticated analysis can use computer-generated CAD drawings to show impacts and areas affected by change.

Written Reports

Written reports can be helpful for review by a judge or arbitrators on large, complex cases. They must be clearly written and professionally produced. Review by an experienced technical editor is highly recommended.

Defense Against Scheduling Claims

Normally, the best defense against a scheduling claim is to attack the following issues:

• The logic and durations of the “as-planned” schedule, as they frequently are inaccurate, incomplete and of insufficient detail.

• The accuracy and completeness of the “as-built” schedule, which are often incorrect in details and have an insufficient level of detail to reflect the true job logic.

• The validity of the “would-have-been, but for” schedule and how the delays are allocated between the parties.

• Whether the computation of damages is adequately proven, given the normal level of detail and completeness of the job records.

• Whether the unimpacted work being compared to impacted work to determine cost differences is truly equivalent to the impacted work. The productivity of unimpacted work may actually be too low if it occurred on the “learning curve.”

• Other items to watch for in contractor claims include:

• Reams of computer printout with tremendous detail, no summary, and few graphics. The contractor may be trying to overwhelm the owner with complexity. Or, hidden features in the scheduling program, such as no credit for out-of-sequence progress, may be used to generate misleading results.

• Excessively simple analyses without supporting detail and linking of cause to specific effect.

• Complex computer scheduling analysis and simulation purporting to prove some theoretical approach.

If the owner has reviewed and approved or even received and not rejected the contractor’s schedule there is an assumption that it is correct and the burden of proof is shifted to the owner.

Although it is less expensive to attack the contractor’s presentation rather than to prepare an independent analysis, in some cases that may be necessary — especially when the claim is thought have some validity but is grossly inflated. If so, the process described in “Creating an As-Built Schedule If Incomplete Data,” supra, is as applicable to a defense of a schedule claim as it is to the plaintiff.

By |January 20th, 2015|Uncategorized|

Can This Project Be Saved?

Associated General Contractors of America
Constructor Magazine – November, 1999
By Steven Pinnell

From a construction perspective, there was nothing remarkable about a recent construction project in Eugene, OR – a high-rise apartment building with a garage underneath.  Project ownership, however, was thoroughly modern: the city would own the public parking garage, a $9 million project, while the apartments above it were to be owned by a private developer.

The problem.
In July 1998, the parking garage, well into its second construction season, was only 70% complete, The owner was threatening liquidated damages for project delay, while the general contractor was considering substantial claims based on problems it encountered with the concrete slabs and block walls.In hopes of moving the project forward, an executive team consisting of city representatives, the general contractor, subcontractors, the private developer, and the project designers met with partnering facilitators to begin a process of intervention partnering known as project realignment.The executive team and project management teams identified specific actions to give the project a fresh start, from improving communications between all parties to changes in quality control procedures. The goal was to resolve all outstanding claims and disputes without litigation. All issues were to be addressed through the change order provisions of the existing construction contract.Project teams performed the specific actions identified in the initial two-day meeting. The teams were built across organizational lines at the field, project-manager, and executive levels, including representatives from the general contractor, the designer, key subcontractors, and the owners, both public and private.The partnering facilitators began holding regular meetings with project executives, project managers, and field personnel regularly. They also put partnering processes in place directly on the jobsite, bypassing the traditional workshop. The facilitators instead met with small groups to lead them in the look-ahead, risk assessment, and issue resolution processes.

A single claims consultant.
Facilitators led the effort to design and implement an issue resolution process that would meet the goals of fairness, speed, and cost-effectiveness. Executives and project managers decided to hire a single claims consulting firm (Pinnell Busch) to objectively assess all claims and issues, with consulting costs shared by all.

Pinnell Busch used sub-consultants, as necessary, to analyze highly technical engineering issues. They interviewed personnel from all the organizations involved in the project and reviewed project records. Time was of the essence, and the executives agreed that the process of issue and claims resolution must be completed within six weeks.  After approximately six weeks of investigation, the claims consultants issued a confidential report containing their opinions on responsibility and damages, or entitlement and quantum.

Confidentiality: the key to success.
Confidentiality was the key to success of the claims resolution process. All parties signed a confidentiality agreement to preclude any from later using the report or the claims consultant against one another if the project realignment failed. The claims consultant’s report was thus nonbinding-but it helped the executive team to understand the claims and positions of each party.

After the report was made, the executive teams and project management teams spent three days in facilitated negotiations. All outstanding disputes and claims were resolved, and the settlements were transformed into change orders and paid through the ordinary course of contract administration.

The parking garage project went on to a successful completion. It proved that a construction project gone badly could be saved through full and open communication and commitment to a win-win solution.

By |January 20th, 2015|Uncategorized|

Scheduling Best Practices to Avoid Changes, Delays, and Claims

The Associated General Contractors of America
Construction News Update – July 2006
By Steven Pinnell and Sarah Pagliasotti Newman

In 2005, Pinnell Busch surveyed construction industry practitioners (or their experiences and recommendations regarding changes, delays, and claims, and how to avoid them. The results indicate changes account for an average of 10% of project costs. Yet for some owners it accounts for only 2% to 3%, while for others it accounts for 15% or more. Clearly some organizations do a better job of managing change than others. But regardless of how your organization is doing now, by implementing some essential scheduling best practices you can improve your processes and outcomes.

Causes of Changes
According to contractor responses; scope changes, design errors, and differing site conditions – in that order – are the three primary causes of change. To reduce changes, Pinnell/Busch has developed the following recommended best practices:

Scope Change
1. Define scope accurately during programming and pre-design
2. Manage cost and scope during design
3. Involve user groups and operations and maintenance in design reviews

Design Errors
1. Select the best-qualified designer with project management skills
2. Don’t over-emphasize design fees-pay more, get more
3. Evaluate performance and use for future selection
4. Utilize constructability reviews and value engineering

Differing Site Conditions
1. Ensure accurate as-builts of new projects
2. Perform risk analysis of site investigation cost vs. benefits

While there is a wide variance in the percentage of changes that turn into claims, the strong correlation between increased changes and increased claims is clear. This is another reason for owners and designers to minimize changes during construction.

Changes also increase the likelihood of delays. More than half of all projects are delayed, and the causes of delays mirror the causes of changes. So the best practices for avoiding delays are those for avoiding changes, plus:
1. Training in critical path scheduling
2. Owners writing better scheduling specifications
3. Contractors preparing better schedules
4. Owner representatives enforcing schedule specifications and tracking progress more closely

Items two and three above are perhaps the most vexing – how do owners write better scheduling specifications and how do contractors prepare better schedules? For owners, Pinnell/Busch has created a draft schedule specification that we recommend as a first step in avoiding some of these common scheduling problems. For example, it requires a narrative description be included, with every update, every month. That kind of detail is often overlooked but can make a big difference in managing a project and in avoiding delays and claims.

Helping contractors prepare better schedules is perhaps a bigger job. Our survey revealed that scheduling performance by all parties – owners, contractors, and owner representatives – was appalling. But contractors, in particular, aren’t necessarily making the connection between poor scheduling performance and delays: three-fourths of those surveyed, including many of those with frequent and/or severe delays, are satisfied with their scheduling practices.

Owners think less highly of contractor scheduling, reporting that only one-third of their contractors are good schedulers, one-third are merely fair, and one-third are poor. Subcontractors also had a dim view of general contractors’ scheduling practices, closely matching the owner perspective. Too few general contractors, they say, request subcontractor input, prepare monthly updates, keep subs informed, or prepare recovery schedules when delayed. Even worse, most hide delays and employ trade stacking.

Pinnell/Busch Vice President, Senior Scheduler and Construction Manager Blake Marchand says those findings match his own assessment of common contractor scheduling mistakes.

“Contractors most typically do three things that undermine a project’s schedule,” Marchand says, “First, they don’t show or use float. Second, they don’t establish a critical path, and third, they don’t provide regular schedule updates to themselves, the owner, or the subcontractors, which means they aren’t using their schedules to reflect current conditions.”

An underutilized schedule is a lost opportunity, Marchand says. And one of the biggest reasons for it is poor initial planning. For a schedule to be truly effective, all parties need to be able to understand it and work with it. For example, Pinnell/Busch worked on a $65 million, three building hotel/condominium project in Mammoth Lakes, Nevada, in 2006, for which the general contractor needed a simplified baseline. The existing schedule was so detailed and fragmented that subcontractors were unable to comply with it.

“I frequently help contractors set up a schedule they can use and that all the other parties can adhere to,” says Marchand. “We focus on creating schedules that have reasonable durations and logical relationships – it’s something that everyone can buy into, which is extremely important.”

Bottom line: Focus on Quality Scheduling
Given all of that, it is safe to say that most contractors could probably stand to fine-tune their scheduling practices. In part, that means training staff on project management. It also means heeding the best practices recommended above, plus:
1. Using partnering to establish a project – first approach with both contractors and owners
2. Creating achievable schedules with realistic lead times
3. Keeping accurate records and increasing staffing on troubled projects
4. Resolving disputes with win/win negotiation and mediation
5. Training for both owners and contractors in contract law and scheduling
6. Timely submittal of and response to notices of change and change order proposals

For more on improving scheduling, visit or contact us at the 503-293-6280.

We refined our original survey, and collected more data in 2006 to compare with the results. Steve Pinnell presented these results at the Association for the Advancement of Cost Engineers International (AACEI) annual conference in Las Vegas in June of 2006. That presentation can also be accessed at

By |January 20th, 2015|Uncategorized|

Construction Defects: Avoiding and Remediating Defects While Resolving Disputes

1. Introduction

Contractors, Architect/Engineers (A/Es), and Project Owners are all at risk from construction defect problems and the ensuing remediation and litigation. Here, we offer some advice on how to avoid defects, remediate those that do occur, and resolve any disputes before they become a claim or lead to litigation.

2. Design Phase – Owner, Architect/Engineer and Building Envelope Specialist

Project Owners control the project scope, select the project team, and require the team to control cost, time, and quality.

Start with a clearly defined scope of work – an ‘architectural program’ for building construction or ‘design criteria’ for engineering works. Then, verify that your budget is based on the scope and that the schedule is reasonable (don’t try to fast track without expert advice).

Next, hire the right Architect/Engineer. Consider their reputation for defect-free design, in addition to project performance, meeting budgets, timely completion, and good project management.

In addition, require your Architect to hire a Building Envelope Specialist to ensure against water intrusion, mold, and costly remediation – that can cost nearly as much as the original construction and often results in costly litigation. The A/E or Specialist should know local environmental conditions – heavy rains, wind and corrosive salt spray at the coast; extreme cold in Alaska and Montana; and moisture problems throughout the Pacific Northwest.

A Building Envelope Specialist is a person, often an architect or professional engineer, who advises on design (or purchase of an existing building), and investigates building envelope defects, identifies solutions, and oversees remediation. They also testify in court or arbitration on means and methods, costs, and who was responsible for the defect.

Architects may need assistance with current Best Practices for building envelope design, in addition to LEEDS, sustainability and other special services – for which the Owner is expected to pay, since they are the primary beneficiary.

3. Construction Phase
Regardless of whether you are using Design-Bid-Build, Agency CM, CM/GC-GMP, or Design/Build,Owners without ongoing construction programs should hire an Owner’s Representative with the expertise to manage the construction process and avoid defects. You also need a Building Envelope Specialist to ensure that envelope construction complies with the design and the workmanship is satisfactory.

Mockups have traditionally been used for aesthetic issues (color, texture, etc.) which are difficult to specify. Now, contracts are requiring mockups of windows, roofing, and other critical building systems to help avoid defects.Owners and A/Es, or their Building Envelope Specialist, need to identify critical building systems that require preparation and testing of mockups. Manufacturers can often assist with mockups.

4. Maintenance and Operation Phase
Contractors should prepare a Building Owner’s Maintenance Guide and require the Owner to acknowledge receipt and agree to follow the guide. This reduces the risk of system failure due to lack of maintenance, which is often blamed on the A/E or Contractor. The Guide and one-year warranty inspections help identify incipient failures, which avoids continued deterioration and collateral damage, and can head off claims.

5. Litigation Phase
If all else fails, be ready for litigation.

Building Owners should determine the statute of repose in their state, and in addition to their regular inspection program, conduct an in-depth inspection before that date, with a focus on the building envelope and other systems that are prone to failure.

If problems are found, hire an attorney familiar with construction defect disputes. You or your attorney should retain an expert to determine the extent of the problem, whether emergency repairs are required, the needed scope of remediation, the probable cost, duration, and the impact on building use.

Contractors or A/Es contacted by an Owner regarding a potential claim, should first (after calling their attorney) get the details and determine whether the problem can be resolved and serious conflict avoided by working with the Owner to fix it. If the Owner is reasonable and if your firm or subs are probably at fault, it is usually best to fix the problem – as long as there are no insurance problems and your Attorney approves.

Attorneys need the most qualified Expert Witness and field investigation team for successful resolution of a construction defect claim. The ideal building envelope expert is a licensed architect (or engineer for engineering projects and building system failures) with experience as a building contractor and in investigating and remediating construction defects. The expert must also have a reputation for credible testimony on the witness stand and the ability to provide solid, direct evidence that gives an attorney the winning edge.

6. Visualizing the Message
Regardless of the project phase, the visual display of information can be your most powerful tool for creating understandable and clear communication.

Good graphics can tell a complex story with little or no supporting explanation. A graphic image can summarize hundreds of change orders, piles of certified payroll, boxes of files, and the consequence of change, delay, impact and bad weather – all on a single sheet of paper.
When presenting graphics, start with the details to ‘build a foundation’ and then summarize it for understanding with a chain of logic from your source documents to your summary charts.

Patrick Melvin, our Graphics Consultant, works with our clients and our Claims, Construction Management, and Construction Defects divisions to communicate complex, data-intensive stories of what happened and why.

By |January 20th, 2015|Uncategorized|