J.S. Daniel paper for practical checklist of schedule

Practical Checking of Schedule of Works
(Baseline and Updates)

Jihad Daniel

18th January 2006

Author: Jihad Daniel Page: 1 of 15


Table of Contents

A- PRELIMINARY

B- INTRODUCTION

C- CHARACTERISTICS OF A GOOD SCHEDULE

D- BASELINE SCHEDULE REVIEW GUIDELINES

D1 - Global Review

D2 - Scheduling Mechanics Review

D3 - Schedule Analysis and Review

E- UPDATED SCHEDULE REVIEW GUIDELINES

E1 - Introduction

E2 - Updated Schedules’ Mechanics Review

E3 - Usage of specialty Primavera Software “Claim Digger”

F- CHECKLISTS IN P3 AND P3c/e

G- CONCLUSIONS



A- PRELIMINARY

Construction scheduling courses concentrate on teaching the basics of schedule
development and the particulars of scheduling mechanics. However, a Planning Engineer,
in addition to developing the project schedule, will also be required to review the baseline
schedule submitted by a prime contractor. Most contracts specify that the successful
contractor submit the baseline schedule within a specified time period (e.g. two weeks
from the notice of award) for review by the Engineer/Owner’s representatives. After the
review and approval process, the contractor revises and resubmits the schedule as the
baseline schedule for the project. An attempt is made in this document to provide a check
list of items which a Planning Engineer can use in the review of contractor-submitted
baseline schedules. Ron Winter Consulting has detailed the technical part of checking a
baseline schedule and briefly stated in “Other Checks” that “other items are to be checked
that are not so quantifiable” and this “expert” other part as prescribed by Ron Winter will
be detailed in this document.

B- INTRODUCTION

The philosophy and the level of detail used in the development of a schedule depend very
much on whether it is a pre-construction schedule prepared by the Consultant for bid
purposes or whether it is a post-award schedule prepared by the contractor to meet a
contract-stipulated project duration. The schedule developed by the Planning Engineer in
the pre-bid stage is generally geared to establishing a reasonable project duration for
inclusion in the bid documents. In such a schedule, deliveries of long lead equipment,
regulatory agency review/approval times, owner imposed constraints, weather
constraints, and availability of resources play a key role rather than any resource
constraints that may be specific to a contractor. On the other hand, the contractor
developed schedules are geared to minimizing the negative cash flow and optimizing the
deployment of available resources (for self-performed and subcontractor work) to
complete the job within the time constraints specified in the contract. The
incentive/disincentive clauses stipulated in the contract also play a significant role in the
contractor-developed schedule. Most contracts specify that the successful contractor
submit the baseline schedule within a given time period (generally 14 days from the
notice of award) for review by the Engineer/Owner. After the review and consent
process, the contractor revises and resubmits the schedule as the baseline schedule for the
project. The baseline schedule is an important project document in that it:

▪ reflects the contractor’s strategy and timetable in the implementation of the project
within the specified contract duration,
▪ is used for all progress updates and to establish all schedule variances,



▪ is used to develop a recovery schedule to recuperate any lost time and to bring the
project back on schedule, and
▪ provides a basis for analysis and resolution of delay claims.

Following is a suggested checklist for use in the review of contractor-generated baseline
schedules. In developing this check list it is assumed that the contractor has also
furnished a back-up copy of the schedule data on a diskette (using Primavera or similar
software) in addition to the hard copies of schedule reports and graphics, together with a
detailed narrative report (Areas of Work, Directory Schemes, Sequence of Works,
Assumptions, Constraints, etc.)

C- CHARACTERISTICS OF A GOOD SCHEDULE

Some project participants care more about their schedules than others. Some contractors
prepare schedules only because it is a contract requirement. On far too many projects a
schedule is created at the beginning of the project and never reviewed or revised until a
problem develops. The best approach is for all project participants to join in the
scheduling process and develop a meaningful schedule, and then use it throughout the
duration of the project. This is most likely to happen when the schedule is realistic,
useable, and understood by all of the project participants. What are characteristics of a
good schedule? Here are a few:

The Plan

All good schedules start with a well thought out planned work sequence. The plan should
consider factors that could impact the timing of the work such as site access, access to
work areas, long lead time equipment and materials, labor availability, and which areas of
the work will take the longest. Once this plan has been established, it should be clearly
communicated to all project participants. It is important to make sure that those not
working on site, such as the engineer reviewing shop drawings or material fabricators,
understand the priorities and planned work sequence.

Subcontractor Input

Generally, construction managers and general contractors are capable of putting together
a schedule without subcontractor input. However, it is the subcontractors who are in the
best position to know their durations and plan their work sequences. For this reason, I
have found that a detailed schedule planning meeting with the major or early
subcontractors is one of the best ways to ensure the schedule has appropriate work
activity durations and sequencing.



Subcontractor input will also confirm durations for shop drawing submittals and material
deliveries. How long will shop drawings take? What time has the manufacturer indicated
for fabrication of materials? The initial schedule will include these activities, but the
subcontractor can help "tune up" the schedule with more accurate information.
Subcontractors can also assist in the schedule updating process, since they are closest to
the actual work. Often they can suggest "work-around" or alternate sequences to mitigate
delays or other field problems.

Schedule Card

One method for coordinating the schedule input of large groups of contractors is a
meeting called the "Schedule Card". The contractors prepare their activities and durations
in advance of the meeting on different colored 3 x 5 cards. Several large calendar sheets
with weekly time increments are also prepared before the meeting. During the "schedule
card" meeting, you "build the building," starting with the earliest work areas. The
activities for each work area are sequenced and arranged by placing the cards on the
calendar sheets and connecting related activities.

In this way, the construction schedule is created in front of the subcontractors. This is a
great opportunity to discuss key sequencing and planning issues. For example, which
subcontractor goes first inside the building, ductwork, or masonry? Will the finishes go
from the bottom floor up or the top floor down? The "Schedule Card Trick" gives all the
subcontractors a chance to see the big picture, as well as where and when their work fits
in the schedule. There is also the added benefit of "buy in" of the schedule by the
subcontractors because they helped put it together.

Explicit Activity Names

Work activities in the schedule should have names that are clear and specific. Explicit
work activity names make it easy to understand what is included (and not included) in the
work activity and when they start and finish. In order to properly track work progress,
the schedule needs separate activities for each trade contractor even if the activities are
scheduled to occur at the same time. "MEP rough-in" is a good example. The plan may
be for them to start and finish together, but you will never be able to identify the
contractor responsible for delaying the activity if they are combined in a single activity in
the schedule. Similarly, it is good practice to separate activities that a certain trade
contractor may do in different time periods or with different crews, such as "framing
walls" and "drywall and tape."



The Right Level of Detail

When construction is just getting started on a project, it is not unusual to find the project
team focused on the earlier parts of the work. As a result, they may not want to take the
time to develop a detailed schedule for work that is a year or more in the future. On
many projects, a detailed schedule will be developed for the site work, structure and
enclosure, and a single long duration activity will be allocated for "interior finish work."
This will work, as long as enough time is allocated in the schedule for the later work and
a future schedule details this work.

A schedule may not be used if it is cluttered with too much detail. Generally, activity
durations should range between one and four weeks. How much to "break down"
individual work activities also depends on how large the work areas are and if a set of
activities will always be done in sequence. It may be all right to combine
"form/reinforce/place footing - east side" if the duration is one or two weeks. One day
activities or milestones signifying the completing of key project activities (i.e. permanent
power available, roof tight, completion of a work stage) are also useful.

Even a large, detailed schedule may not provide all the specific activities needed in the
field or may be too cumbersome to use on a daily basis. For these reasons, field staff
often develop short-term, hand drawn schedules to coordinate day to day activities among
subcontractors. This is an acceptable practice if the durations and sequencing in these
short-term schedules are consistent with the "official" project schedule. Significant
differences between the two schedules are indications that there may be a problem with
the overall schedule because it is not accurately reflecting the work being performed in
the field.

Well Organized Activity Groupings

The typical construction schedule on a large project will include hundreds or even
thousands of activities. To make the schedule useable, it should be structured so these
activities can be sorted and grouped, making it easy to find desired schedule information.
Generally, activities can be separated by phases, such as bid/award, shop
drawing/fabrication, new construction and renovation. It is helpful if the activities can be
sorted by bid package or specification section within these categories.

It works best if the groupings of activities correspond to the planned work areas and
sequences (i.e. how you are planning to "build the project"). For example, if the interior
work on the floor of a building will be completed all at once or in two phases, or by
specific functional areas (Administration Area, Classrooms, Library, etc.), it is important
to create schedule activities for each work area.



Breaking work into smaller pieces in the schedule also allows better tracking (for starts
and finishes) and better logic (the following activity will probably start sooner). Areas on
bridge and road projects are often sub-divided by survey stations or work phases.

Proper Consideration of Weather

Once a detailed schedule has been developed and the expected start date for the work is
known, the project team should review the activities in relation to the time of year in
which they are scheduled. In cold weather climates, activities which fall in the winter
months may need to be shifted, or it may be necessary to plan for temporary enclosure
and heating. Similarly, the schedule may need to allow more time for certain activities or
show them being done on a limited basis because of weather considerations. Similar
issues may arise in extremely warm areas or areas which have a rainy season.

If a revised project start date or other delays shift the work by several months, the
schedule should be updated and the activities that have shifted into bad or difficult
weather periods should be looked at closely and adjusted as needed to reflect the effect of
weather. This is one of the most often ignored aspects of preparing and updating project
schedules; when not considered and planned for, seasonal effects can significantly impact
the project cost and schedule.

Finally, to use the schedule. Hang a large plot on the wall at the jobsite. Write on it,
noting actual starts and finishes, and make notes about changes and new issues. Put the
new updates on top of older versions (which are very likely to be referred to by those
who are really watching the schedule). Refer to it daily with the subcontractors.
Formally review current activities at all regular subcontractor meetings.

Awareness of the schedule and delays will allow for better planning and a smoother job.
Throughout the project, be "schedule conscious." The schedule itself may experience
delays, but time will move on.

D- BASELINE SCHEDULE REVIEW GUIDELINES

D1. Global Review

This is a quick check to establish whether the schedule submitted by the Contractor
conforms with the overall time requirements specified in the contract:

1. Notice to proceed (N.T.P.) date
2. Project start date



3. Project duration in terms of completion date or number of calendar days specified
from the N.T.P. date
4. Schedule to show an EPC form (Engineering, Procurement and Construction)
program of work or not. It depends on type of Project undertaken by the
Contractor: EPC turnkey, DBO (Design, Build and Operate), etc.
5. Intermediate milestone completion dates, interface milestone dates and/or
beneficial occupancy dates
6. Owner-imposed date constraints, e.g. access to job site, shutdown periods for
maintenance, restricted work periods due to other contractor’s activities, holiday
and winter work constraints
7. Scheduling method to be used, e.g. Arrow Diagram Method (ADM), Precedence
Diagram Method (PDM)
8. Schedule documents submittal, e.g. schedule reports sorted by Early Start, Total
Float, 60-day Look-Ahead, Activity ID, Area, and schedule graphics such as Bar
Charts, Pure Logic Diagrams, Time Scale Networks
9. Cost and Resources’ loading of activities (not all contracts specify cost-loaded
schedules) e.g. if schedule is loaded with man-hours, to compare first the
summary of total man-hour with man-hour at completion and remaining man-hour
(same can be done with cost load, cost at completion and remaining cost to
complete) if error occurs in the figure, to check each loaded activity.

D2. Scheduling Mechanics Review

Primavera scheduling programs can generate a diagnostic report which can be very
useful. In addition to providing scheduling statistics this report also includes:

1. Number of activities started and completed. Because the schedule data date
should be the same as the project start date, baseline schedules should not show
any progress or actual start dates.
2. Scheduled start and completion dates. These dates can be verified against the
project start and completion dates specified in the contract.
3. Listing of open ends. This is a list of all activities not having predecessors and
successors. Ideally, in a properly developed network only the starting activity has
no predecessor and the ending activity has no successor. Networks with many
open ends will result in an erroneous critical path and unrealistically high float
values.
4. Listing of date constraints. This is a list of all activities with imposed date
constraints. While date constraints can be imposed on specific activities (e.g.
procurement items, interface work), excessive usage of date constraints in lieu of
network ties may lead to inaccurate schedule computations.



5. Listing of milestones. This is a list of activities identified in the schedule as start
or finish milestones. This list can be used to check conformance with the
milestones specified in the contract.
6. Number of relationships: usually this number should be double of the total
number of activities.

D3. Schedule Analysis and Review

1. Activity durations. Check the reasonableness of the activity durations with
regard to the quantities of work involved. Planning Engineer needs to calculate
ratio of quantities per day for a certain traded activity and compare it with similar
one (Justification to be made by the Contractor’s Planner if ratio varies for the
same trade: additional resources, etc.)
2. Schedule logic. Check whether all the activities are networked using the
diagnostic check. In addition, examine the validity of the relationships in terms of
normal construction practices. For example, too many activities with a number of
start to start relationships with time lags (i.e. excessive number of concurrent
activities) can create "stacking" of trades. This can lead to problems associated
with resources, construction safety and jurisdictional issues.
3. Nomination of Subcontractor: In the case of provisional sum allocated in the
contract, the Contractor needs to indicate the dates in which in his opinion
nomination shall become due by the Engineer in order to have enough time to
review documents, arrange for drawings and enter into Sub-Contract agreement
with the nominated Company. These nomination dates need to appear on the
schedule and linked to the preparation of S/C documents & agreement then to
preparation and issuance of submittals.
4. Conformity to Specifications and Construction Method Statement: Check
whether construction activities are complying to project specifications (i.e. if
according to civil Specifications, suspended slab’s scaffold cannot be removed
before 21 days in order to start masonry work in the underneath floor, this needs
to be reflected on the schedule with a lag of 21 days between these two activities
or an added activity of scaffold’s removal). Also check the conformity to normal
construction method statement (i.e. if according to Waterproofing Method
Statement of Tanks, no work is allowed to proceed directly after water tank’s
insulation, before executing a water test for 2 days. This activity of water test
needs to be reflected on the schedule according to the related construction method
statement).
5. Project calendar. Check the correctness of the project calendar in terms of the
work day/work-week calendar (5-day, 6-day, 7-day/week) along with non-work
periods (weekends and holidays) and shutdown periods (i.e. project calendar
depends on each Country’s calendar (start of the week and non work days) and



Project’s Phases (i.e. in industrial Oil & Gas projects, in a shut down period, work
can be limited to certain days per week or few hours per day with special permit
to work in these shut downed areas). Attention should also be paid to schedules
with multiple calendars where different activity durations are expressed in work
days and calendar days.
6. Critical path. The initial critical path should always be reviewed carefully to see
if it makes sense. Having a correct critical path will help the project team
prioritize shop drawings and field work. If delays occur, it will identify what
work to focus on in order to reduce further slippage or make up lost time.
Without an accurate critical path, Contractors can make good progress on non-
critical activities, while the forecast end date is actually slipping, undetected. A
good rule of thumb on public projects is that no more than 10-15% of the
schedule activities should be critical or near critical. Utilizing this practice allows
for the normal minor slippage and delays in some areas that occur on any
construction project. Resources, particularly manpower, are often the real limiting
factor and dictate the timing of work activities and the critical path, rather than the
activity sequencing. Most schedules are not resource-loaded, so the impact of
limited resources is sometimes difficult to see and address. A narrative of
planned manpower and crew sizes at different phases of a project can help an
Owner evaluate whether the schedule provided is realistic or not. The critical path
in the Contractor's schedule can be manipulated by the Contractor to a certain
degree and may not reflect the actual critical path of the project. The Contractor
may link work areas in the schedule that are not really dependent on each other,
add mandatory start dates, or otherwise use the scheduling software to make the
critical path include work activities to support a future delay claim. Schedules
with multiple critical paths and/or too many critical activities indicate a very tight
schedule. Such a schedule needs a careful examination for possible manipulation
of the critical path that could set a stage for future delay claims. In addition, it is
necessary to examine activity paths which are near critical and sub-critical. These
activities have very little float (usually, in the range of 1 to 10 days) and could
become critical even when minor changes in the field conditions occur. The
Planning Engineer should also examine specifically the activities for which the
owner and/or his representatives are responsible and ensure that adequate time is
allowed for accomplishing these activities. Activities which fall under this
category are: construction permits, shop drawing review and approval procedures,
material review and approval procedures, change order processing, traffic
rerouting plan approvals and utility relocation work. It is obvious that any delays
caused in the completion of these activities will come under owner-caused delays
and result in costly time extensions.
7. Is the Contractor's Schedule a "Steep Staircase" Schedule? Does the
Contractor's schedule show a large number of work activities scheduled to be



done at the same time? In particular, look out for "stacking" during the last half
or third of the project time frame. This may indicate an unbalanced schedule with
too much time provided for the structure and building shell and not enough time
for interior finish work and completion activities, such as start-up and
commissioning. A steep staircase schedule may also result from inadequate
consideration of manpower when work activities slip on projects with delays.
This is sometimes referred to as "schedule compression." On most projects, a well
planned schedule, whether it is a baseline schedule or a schedule update, will have
an even distribution of activity bars in time rather than a steep staircase of work
activities. Too many activities shown going on at the same time is usually not
realistic and schedules like these are often not achievable. To assess this
situation, think about the manpower or number of crews that would be required to
start and finish 25 or 30 activities (or more) in a month, and think about the
manpower likely to be provided by the subcontractors. Will there be adequate
manpower?
8. Does the Contractor's Schedule Allow Enough Time for Completion of
Activities? The Contractor may not worry about all the things an Owner needs to
do after construction is substantially complete to make the project fully useable by
the Owner. Typical completion activities include preparing and completing the
punch list and clean-up, validation or start-up and testing of special systems (fire
alarm, smoke evacuation, telephone and data, CCTV), move-in and installation of
Owner furnishings and equipment, and contractor closeout (as-builts, O&M
manuals, warranties). It is important to include these activities in the schedule, so
that all parties have a clear understanding of what will occur at the end of the
project and the Owner's true occupancy date.
9. Are You Late Before You Start? You may be surprised to hear this, but in my
experience this happens a lot. Significant time lost at the project's front end is
made up simply by compressing the construction schedule, thus creating a
"spring-loaded" schedule. Unless significant resources are added, the schedule
will most likely "spring back" to a more realistic duration. The effect of work
shifted into different weather periods can also have cost or schedule impacts.
When there is slippage of more than one month up front for a construction
schedule of twelve months or longer, Owners should resist the temptation to
shorten the construction duration and adjust their overall project schedule instead.
10. Float analysis. It is also important to identify activities with excessive total floats.
These activities are generally associated with open ends, date constraints and
inaccurate logic. It is necessary to correct the logic and bring the float times to
realistic levels so that the available resources can be more effectively used.
11. Long-lead procurement activities. Most procurement items (such as structural
steel, process equipment) will have to go through the shop drawing review and
approval cycle before fabrication can begin. The shop drawing submittal and



review turnaround times shown in the schedule should be consistent with the
contract documents. Check for schedule conflicts in the coordination of the
interface shop drawing review process between two vendors on early delivery
items. For example, anchor bolt pattern details and delivery of embedment may be
required early for an equipment support foundation even though the equipment
itself is not installed until a later stage. The delivery schedules shown for any
owner-furnished equipment should also be consistent with the schedule data
furnished in the contract documents. In situations where equipment installation
contractors and vendors are separate, it is important to check the equipment
delivery schedules against the timely availability of unloading equipment/crews,
and covered/secured storage areas on the job site. The Planning Engineer should
be aware of materials’ scope’s split between the Contractor and the Owner and
should differentiate on the schedule between the free issued Owner’s materials,
the Contractor’s permanent materials and materials procured by Contractor on
behalf of the Owner .
12. Readiness Checklist of E/M systems: Check if all E/M systems and items have
activities called readiness to perform testing. After completing the installation of
any E/M system or equipment, the Contractor together with the Engineer’s
supervisor needs to check if system is completely ready to perform the required
testing. This should be shown on the program of works before proceeding with
testing & commissioning schedule of works.
13. Other Assigned Contractors’ Works: Check if all activities on the schedule are
in the scope of the Contractor’s work as per the Contract. Check also if works are
related or need to be coordinated with other Contractors on site. Coordinated
Schedule between different Contractors on site is the responsibility of the
Planning Engineer unless otherwise instructed by the Owner. Each Contractor has
to reflect his own schedule of work irrelevant to the other Contractor working on
site, unless it is specifically mentioned these constraint dates in the Contract. In
all cases, the Contractor has to indicate that his work belongs to other parties and
its own succeeding work depends on the completion of the other parties’ work.
14. Weather Conditions. Examine the nature of work performed (e.g. concrete,
earthwork) and productivity levels achieved during winter months and/or periods
of adverse weather. Check for curtained period indicating harsh winter season or
forecasted very hot weather where only particular works can be performed during
these periods.



E- UPDATED SCHEDULE REVIEW GUIDELINES

E1. Introduction

In reference to Ron Winter “119 schedule update checks”, once the difficult part of
checking a baseline schedule is consented upon, it is easy for the Contractor’s Planner to
make the updates based on site inputs. In the narrative report submitted together with the
updated schedule, the Contractor’s Planner needs to state all changes and modifications
that he made to the schedule and the reasons to do so. Consultant to check the inputs
made to the schedule based on realistic site information and figures, also to review
thoroughly the changes made and assess their outputs to the best interest of the Project
and the Client. In addition to Ron Winter checklist, we list herewith the other items:

E2. Updated Schedules’ Mechanics Review

The scheduling statistics that Primavera provides for both baseline and update will be
compared together and following report will result:

1. Constraint listing: to check and compare to see if any constraint or milestone was
added or deleted.
2. Open end listing: it is not permitted in an updated schedule to have a successor
started or completed and his FS predecessor not started or finished yet. Also, to
check if all activities have predecessors and successors (except for the 2 activities
of start and finish Project).
3. Schedule statistics showing schedule & float calculation modes, number of
activities, relationships, etc. A brief comparison will give an idea about the
changes made to the schedule and the latest calculated finish date.
4. It is advisable to run the program in two schedule calculation modes: retained
logic and contiguous activities and compare both statistics report in order to check
the variance of delayed days (if any) and the calculated finish date, also to
identify number of activities in longest path and out of sequenced ones.

E3. Usage of specialty Primavera Software “Claim Digger”:

Usage of special software like Claim Digger or Schedule Analyzer allows us to have a
report of all the changes made to an updated schedule. Also to back track changes
happened between several schedule updates before we could begin our delay analysis.
Primavera Claim Digger v3.0 is the market leading schedule analysis solution enabling to
compare P3 project schedules, perform impact analysis, and document delays to the
schedule.



The software provides comprehensive schedule comparison capabilities by checking:

• Autocost and Schedule logic rule changes
• Activities that have been added or deleted
• Changes to original and remaining durations
• Changes to constraint types, percents complete, total and free floats
• Changes to activity calendars
• Changes to descriptions
• Changes to activity logs
• Changes to actual starts and finishes
• Adding or Deleting Resources
• Changes to resource and cost budgets, actuals and forecasts
• Changes to resource percents
• Activities that have jumped on or off the critical path
• Added, deleted or changed relationships
• Changes to driving relationships, activity codes and WBS changes
• Activities that should have started or finished in a reporting period - but did not.

Reports can be printed or viewed in detail. Primavera Claim Digger exports to Word or
Excel at the push of a button. In addition, the complete data analysis of all changes is
available in a text file for custom reporting.
Primavera Claim Digger can handle schedules of any size. The program is fast - a 1000
activities schedule can be compared in a little over a minute.

F- CHECKLISTS IN P3 AND P3c/e:

Although checklists presented by Ron Winter Consulting LLC are generalized as much as
possible for all CPM software, they are much more oriented to Primavera Users and
mainly to P3. As we know, the new Primavera version P3c/e is much more performed
than P3 and has much more commands/options than the previous version. Migration from
P3 to P3c/e cannot be done as soon as we think and we cannot impose immediately the
use of this new version by Contractors in recent contracts. Due to the facts that we cannot
wait longer for implementing this new version, P3 schedules can be checked by
transferring them to P3c/e software. In order to prepare our own check lists relevant to
P3c/e we need to be first familiar and acquainted with this new software and its Claim
Digger.

G- CONCLUSIONS

This document developed above, while by no means exhaustive, has been the result of
many years of experience in Planning. Schedules are sometimes put together quickly by



people who are also busy with other tasks and errors occur through oversight as much as
anything else. And, yes, there are Contractors who think they can gain an advantage by
playing games with their schedules. Common sense and an independent review are the
best tools to assure a good schedule and maximize our most limited resource - time.
Inputs are welcome so that the material presented can be further streamlined.


J.S. Daniel paper for practical checklist of schedule

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