Category: Schedule Review Process

Basic Schedule Review Process

Construction Scheduling. Schedule Performance Measurement, Part 5. (For Owners).

When monitoring and responding to the Contractor’s schedule performance on the project, how do you know if the schedule update is even valid for use?

When we review a schedule progress update, we need to first determine if the schedule update is a valid update. By that, I mean is the logic still complete? Have there been any revisions with this update that result in the schedule not meeting the contract requirements or best practices? It doesn’t take much to render a schedule useless….

There are most likely logic revisions, changes to lag values, or possible changes to calendars or assignments. There are also deletions and additions of activities and/or Activity Relationships. Then there are changes to quantities or Resources which may impact Activity Durations or Resource Calendars.

For this post, we will address the lack of correcting Out-of-Sequence, OOS Logic.

Personally, the first schedule “quality check” I make is for complete logic. Please see the previous post, Schedule Performance Measurement, Part 2. (For Owners).

Next, I check for changes to Relationships and Relationship Lags. Please see the previous post, Schedule Performance Measurement, Part 3. (For Owners).

I then check for changes to Activity and Relationship Calendars and Calendar assignments.

But, my personal pet peeve is OOS Logic which has not been addressed.

When the Contractor is assigning actual and expected dates to the schedule update, while assigning the current progress for work in progress, it is common and acceptable for actual work in the field to have been executed differently than planned. This results in Out-of-Sequence, OOS Logic.

Primavera P6 provides a Schedule Log with lots of information. One of the things this log provides is a list of activities with OOS Logic. This is simply a list of activities with assigned Actual Dates which are not progressed the same as the Schedule Network Logic.

For example, if activity A drives activity B with an FS Relationship and Activity A is assigned an Actual Start Date with a projected scheduled Finish Date and activity B is assigned an Actual Start Date, activity A will show up on the Schedule Log as having OOS Logic because activity A does not have an Actual Finish Date prior to activity B actually starting. This condition is simple to correct. We simply change the logic to an SS relationship. This allows the as-built relationship to match the revised logic. If activity A has not actually started and activity B is assigned an Actual Start Date, then more work must be done to correct the OOS logic. Activity A is obviously either not progressed and missing the Actual Start and Finish dates or the actual sequencing of the work is being executed differently than planned and activity A should no longer be the predecessor to activity B.

If the issue is OOS logic, it should be addressed. Leaving OOS logic in the schedule allows the now incorrect logic to drive the successor activity dates, which is incorrect. This happens when we use Retained Logic, which most schedule specifications require. It is also best to use Retained Logic to allow the planned logic to drive the schedule. We just have to correct the OOS logic with each update.

Not correcting OOS logic with each update can produce erroneous specific Network Path scheduled activity dates. This can create a Critical Path based on the original logic which is no longer valid due to the actual OOS work in the field. We want the Critical Path, and Near Critical Path(s) to be based on the most accurate progress input and plan to execute the remaining work.

Typically, correcting OOS logic for driving activities on the Critical Path will shorten the Remaining Duration of the Project Schedule. I prefer to correct the OOS Logic immediately after I assign the actual dates, expected dates, and actual progress. This way, when we need to determine the best method of recovering any lost time, we are working with a valid Schedule Network.

The same applies to Near Critical Path(s).

That said, understanding the impact of the uncorrected OOS Logic, and reporting those findings is important to the Owner. Personally, I do not consider the Schedule Update valid if the OOS Logic is not corrected. But many schedule specifications do not address this issue.

As  Planning and Schedule Professionals, we need to provide the Project Team with the “tools” they need to manage the project. The owner needs to know what the performance of the actual work in the field is, compared to the planned performance. Unless we have a valid schedule update to measure with, and against, and understand the impact of acceptable schedule revisions, we cannot provide an accurate measurement.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Schedule Performance Measurement, Part 4. (For Owners).

When monitoring and responding to the Contractor’s schedule performance on the project, how do you know if the schedule update is even valid for use?

When we review a schedule progress update, we need to first determine if the schedule update is a valid update. By that, I mean is the logic still complete? Have there been any revisions with this update that result in the schedule not meeting the contract requirements or best practices? It doesn’t take much to render a schedule useless….

There are most likely logic revisions, changes to lag values, or possible changes to calendars or assignments. There are also deletions and additions of activities and/or Activity Relationships. Then there are changes to quantities or Resources which may impact Activity Durations or Resource Calendars.

For this post, we will address changes to Activity or Relationship Calendars.

Personally, the first schedule “quality check” I make is for complete logic. Please see the previous post, Schedule Performance Measurement, Part 2. (For Owners).

Next, I check for changes to Relationships and Relationship Lags. Please see the previous post, Schedule Performance Measurement, Part 3. (For Owners).

I then check for changes to Activity and Relationship Calendars and Calendar assignments.

When the Contractor is making schedule revisions to recover lost time for the update period, they may decide to work a crew more than the Activity or Relationship Calendar currently allows. If the Activity is assigned to a 5 Day Workweek with Holidays and Weather Days, they may decide to work 6 days a week for a specific resource to recover lost time. To be able to do this, they need to create an additional Calendar and set the work days up accordingly. They then replace the existing Calendar with the new Calendar. This allows the same amount of work, or Work Day Duration, to be scheduled over fewer Calendar Days. This results in shortening the Calendar Day Duration of the Activity Network(s) which contain the affected Activities.

This is the kind of schedule revision the Owner must be aware of and understand. It can be checked for in Primavera P6.

What Primavera P6 is not good at checking are changes to the work days in an existing Activity or Resource Calendar. As long as the Calendar Name does not change, P6 does not report it.

Most of us use third-party software designed to identify changes to Calendars. That’s great, but we still need to understand the impact of the changes identified.

Changes to Calendars and the Work Days in a specific Calendar do not make the schedule invalid for use. But, the owner needs to know what changes were made and what effect the changes have on the affected Logic Path(s).

That said, finding the changes to any Calendars, understanding the impact of the changes found, and reporting those findings is important to the Owner.

As  Planning and Schedule Professionals, we need to provide the Project Team with the “tools” they need to manage the project. The owner needs to know what the performance of the actual work in the field is, compared to the planned performance. Unless we have a valid schedule update to measure with, and against, and understand the impact of acceptable schedule revisions, we cannot provide an accurate measurement.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Schedule Performance Measurement, Part 3. (For Owners).

When monitoring and responding to the Contractor’s schedule performance on the project, how do you know if the schedule update is even valid for use?

When we review a schedule progress update, we need to first determine if the schedule update is a valid update. By that, I mean is the logic still complete? Have there been any revisions with this update that result in the schedule not meeting the contract requirements or best practices? It doesn’t take much to render a schedule useless….

There are most likely logic revisions, changes to lag values, or possible changes to calendars or assignments. There are also deletions and additions of activities and/or Activity Relationships. Then there are changes to quantities or Resources which may impact Activity Durations or Resource Calendars.

For this post, we will address changes to Relationship Lags.

Personally, the first schedule “quality check” I make is for complete logic. Please see the previous post, Schedule Performance Measurement, Part 2. (For Owners).

One of the things that are really hard to check, using Primavera P6, is changes to Activity Relationship Lags.

Often, when the Contractor is making schedule revisions to recover lost time for the update period, they make subtle changes to logic. They also make changes to the Relationship Lag values assigned to specific Activity Relationships. If they have modeled the sequence of work using SS Relationships with Lags, they may reduce the Lag value for an activity, driven by the Activity Relationship with the Lag, to gain a day or so. If there is an FS Relationship with a Lag, they may reduce that lag value as well.

They can also change the Relationship Lag’s effect by changing the Activity Calendar of the Activity selected to determine the Relationship Lag’s behavior.

None of this is easy to check in Primavera P6 and is not readily transparent in a Gantt Chart.

Most of us use third-party software designed to identify changes to Relationships and Relationship Lags. That’s great, but we still need to understand the impact of the changes identified.

Changes to Relationship Lag values does not make the schedule invalid for use. But, the owner needs to know what changes were made and what effect the changes have on the affected Logic Path. Some specifications prohibit the use of Relationship Lags. Many specifications allow limited use and do not allow the use of negative Lags at all. I prefer to minimize the use of Lags and do not like to use Negative Lags. There are conditions which warrant the use of a Negative Lag, but the condition has to be monitored and other options for modeling the work sequence should be exhausted.

That said, finding the changes to Relationship Lags, understanding the impact of the changes found, and reporting those findings is important to the Owner.

As  Planning and Schedule Professionals, we need to provide the Project Team with the “tools” they need to manage the project. The owner needs to know what the performance of the actual work in the field is, compared to the planned performance. Unless we have a valid schedule update to measure with, and against, and understand the impact of acceptable schedule revisions, we cannot provide an accurate measurement.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Schedule Performance Measurement, Part 2. (For Owners).

When monitoring and responding to the Contractor’s schedule performance on the project, how do you know if the schedule update is even valid for use?

When we review a schedule progress update, we need to first determine if the schedule update is a valid update. By that, I mean is the logic still complete? Have there been any revisions with this update that result in the schedule not meeting the contract requirements or best practices? It doesn’t take much to render a schedule useless….

There are most likely logic revisions, changes to lag values, or possible changes to calendars or assignments. There are also deletions and additions of activities and/or Activity Relationships. Then there are changes to quantities or Resources which may impact Activity Durations or Resource Calendars.

For this post, we will address changes to the logic.

Personally, the first schedule “quality check” I make is for complete logic. The Primavera P6 schedule log provides a basic check. But I also use third party software that provides a more in-depth check for activities which may only have an SS relationship to their only successor activity. Sometimes, the check uncovers missing lag values or “reverse logic”. It may even uncover an SF relationship. All of these must be identified and addressed.

Often, when the Contractor is making schedule revisions to recover lost time for the update period, they make subtle changes to logic. As a Project Owner or CMa, we need to understand what was revised and why. If the relationship for an activity in the current or previous period Longest Path was changed from an FS relationship to an SS relationship, with or without a lag, to pull the scheduled Finish Date back, we need to understand that.

The same applies to the previous period or current update Near Critical Path(s).

If the contractor makes a logic revision for an activity which results in the only successor activity having an SS relationship, an open end is created. (There should have been an FS or FF relationship added to complete the logic). Otherwise, the finish of the activity does not drive anything in the schedule. This is an open end, (which does not show up on the Primavera P6 schedule log).

Any “open end” relationships make the schedule network logic incomplete. Sure, there are activities that once complete will not drive any other activity or work until the project is complete, if that is the case, they should be tied to Final Completion or whatever the last activity in the schedule is called. But more likely, the activity relationship was missed during development or when making revisions.

However, if this activity is supposed to drive other work, the relationships should model this. Not having complete logic for just one activity results in an erroneous schedule network. The activity could potentially be Critical or Near-Critical, but without the complete logic, there is nothing in the schedule to model the intended sequencing of the work for the affected network path. This means the Total Float values and scheduled dates for driven successor activities on this logic path are incorrect.

One of the basic checks and the first check I make is to verify the schedule network logic is complete. As an owner’s rep, we cannot know the detailed intent of the schedule sequencing, but we can identify open ends and any questionable logic we discover.

As  Planning and Schedule Professionals, we need to provide the Project Team with the “tools” they need to manage the project. The owner needs to know what the performance of the actual work in the field is, compared to the planned performance. Unless we have a valid schedule update to measure with, and against, and understand the impact of acceptable schedule revisions, we cannot provide an accurate measurement.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Schedule Performance Measurement, Part 1. (For Owners).

Are you responsible for monitoring and responding to the Contractor’s schedule performance on the project?

Do you review each schedule update and compare dates in the new update with the dates in the baseline schedule?

Do you compare the Milestone Activity dates to the baseline schedule?

There are many different methods of analyzing project schedule performance.

When we review a schedule progress update, we need to first determine if the schedule update is a valid update. By that, I mean is the logic still complete? Have there been any revisions with this update that result in the schedule not meeting the contract requirements or best practices? It doesn’t take much to render a schedule useless….

There are most likely logic revisions, changes to lag values, or possible changes to calendars or calendar assignments. There are also deletions and additions of activities and/or Activity Relationships. Then there are changes to quantities or Resources which may impact Activity Durations or Resource Calendars, depending on the schedule settings selected.

This should all be addressed in a manner that conveys the actual revisions with the reasons for the revisions as part of the schedule update narrative the Contractor submits with the schedule update. Unfortunately, this is rare. Typically, we see the “digger” report with a general comment addressing the high-level view of the update.

Not really helpful for our use.

So, we plow ahead with the intent to complete our review of the schedule update for this period.

First, we need to complete several “quality checks” of the schedule to validate it for use.

In my next post, I will walk through some of the more common items we check for.

Until then, be suspect of schedule updates without, or with vague schedule update narratives. There is much that can be changed in the program, that will not be transparent to the owner without a thorough review and analysis of the file by an experienced schedule professional.

As  Planning and Schedule Professionals, we need to provide the Project Team with the “tools” they need to manage the project. The owner needs to know what the performance of the actual work in the field is, compared to the planned performance. Unless we have a valid schedule update to measure with, and against, and understand the impact of acceptable schedule revisions, we cannot provide any accurate performance measurement.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Is the Schedule a Complete Schedule? (For Owners).

Do you review your Baseline Schedule to make sure all the work to complete “The Project” is included?

Are you sure?

When the contractor develops the schedule, they should be planning the project execution first. This includes the phasing of the project, the necessary permits, the long lead submittals, the procurement of subcontractors, equipment, and material, the close-out of the project, and the actual work necessary to build the project.

Often, we see schedules which do not include permits, or the procurement of long lead items, or complete commissioning, testing, and inspections. Let’s not forget the closeout requirements for as-built documents, warranties, or training, (if required).

The CPM schedule should include all the work necessary to execute the project.  An easy way to ensure all the work is included is to make a list of all the closeout deliverables and compare that to the WBS for closeout section of the schedule. The same for special inspections, commissioning. For whatever reason, we always look closely at the construction section of the schedule, but tend to gloss over the administrative, procurement, and commissioning sections.

Just as we look at constructability for the project plans, we need to thoroughly look at the project schedule to make sure all of the deliverables are included. And, the activities to provide these deliverables need to be complete and broken down into sufficient detail to control the work!

An activity at the end of the project schedule that says “Finish Project” is of no use. All the activities necessary to actually plan and control the post “Substantial Completion” work for the project should be as detailed as the construction work is. The same for the commissioning and testing of systems.

And, let’s not forget the initial administrative requirements which have to be fulfilled prior to starting any work. We usually need an approved Safety Plan, an approved environmental permit, and building permit at a minimum. The time to develop these, get them submitted and reviewed and approved needs to be in the front of the schedule.

Also, we need the long lead time equipment or material submittals in the schedule. I also like to have the main materials submittals, in general form, in the schedule just to make sure we get them in and reviewed in time for their use in the project. Often, the contract documents state the required review period for the owner. We use this for the review period in the schedule.

There should be a fabrication and delivery activity(s) for any major equipment which should drive the start of any installation of the equipment. This activity(s) should be driven by the submittal and procurement of the equipment. Often, this will drive the Critical path.

Everyone tends to really look at the construction activities. As  Planning and Schedule Professionals, we need to look at the project deliverable as a whole.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. “All the Other Work” Progress Update Information for Owners.

As a continuation of my previous posts, I will continue to discuss some of the important progress update items we review and analyze.

I will now discuss the process of analyzing the actual performance of work NOT on the Critical and Near Critical Path(s).

When the contractor adds the actual Start and Finish Date and expected Finish Date data to the schedule update, the new scheduled completion date if most often not what any of us want. Usually, there has been slippage in work progress in an area that must be addressed.

This is most often caused by a lack of adequate progress for work on the Critical Path and/or the Near Critical Path(s).

However, we must not forget to monitor and address non-performance for work not on the Critical Path or Near Critical Path(s).

One of the reasons we work to make the schedule logic as complete and defined as possible is to allow the planned sequencing of finite work activities to drive the schedule. This provides a dynamic logic network for the planning and control of the project.

The result of all the work breakdown, resource allocation, and logic assignments produces multiple network “paths” through the schedule. The paths we’re always looking for is the Critical Path, and then the Near Critical Path(s). These are determined by the scheduling algorithm and have Total Float values based on this calculation.

But what about the “other” activities that are not Critical or Near Critical? They have higher Total Float values, so they can be done anytime as long as we don’t let them get Critical, right?

That is not a good idea. I believe it is best to complete the work, when you can; efficiently, of course. Letting the work push out because it is not “Critical” or has “Float” only sets the project up for failure.

If you’re cost or unit loading the schedule, you typically produce a Baseline Curve of some sort to plot the resource or cost spread over time. This curve is comprised of all the activities. Letting work slip pushes the curve and the required cost and resources out and this can quickly overwhelm the availability of resources to complete the work when it “stacks” up. Unfortunately, this is all too common.

Many Superintendents push their work everywhere, all the time, and for good reason. They learned early on that letting work slip will come back to haunt them.

The owner needs to monitor for work slippage. The project can easily show an on-time completion with the Critical Path looking very pretty. But, they should also be concerned with the Schedule Performance Indicator. This will show if work is pushing out because the projected curve will push out. Of course, we have to balance the work, so we maintain the curve and the Critical Path to achieve on-time completion, in the most cost-effective manner. This is another item the Owner’s scheduler should be analyzing and reporting on. We can list activities which did not start as planned, did not finish as planned or could have started but did not. We can also list activities which have started but made little or no progress. While there are going to be valid reasons for some work not starting, finishing or progressing as planned, the reasons should all be explained in the schedule update narrative provided by the contractor. They know the reasons and can best explain them. If they do not provide this information, the project team really needs to investigate and determine what is driving the slippage. It is much better to tackle this kind of problem early. It is rare that a project can recover if slippage continues very long at all.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Critical and Near Critical Progress Update Information for Owners.

As a continuation of my previous posts, I will continue to discuss some of the important progress update items we review and analyze.

I will now discuss the process of analyzing the actual performance of work on the Critical and Near Critical Path(s).

When the contractor adds the actual Start and Finish Date and expected Finish Date data to the schedule update, the new scheduled completion date if most often not what any of us want. Usually, there has been slippage in work progress in an area that must be addressed.

This is most often caused by a lack of adequate progress for work on the Critical Path and/or the Near Critical Path(s).

Quite simply, the planned productivity for the work scheduled is not achieved.

To analyze this, we compare the previous period update Critical Path work to the actual progress reported in the current period update schedule. We simply compare Original Duration and scheduled dates to the actuals. This tells us where the slippage occurred. It does not explain the why. This should be included in the schedule update narrative the contractor provides.

We do the same for the Near Critical Path(s).

Why do we do this?.

The contractor typically knows what is driving the project and what measures need to be taken to correct work slippage. The owner usually does not have this intimate knowledge of the background operations of the contractor. However, the owner is entitled to know as much as possible about the actual and planned performance of the project. They need that information to make internal business decisions which may impact the project, such as potential change orders and work integration by others, or to react to deviations from the planned contract milestone dates.

More importantly, to me anyway, the owner is always in a position to help the contractor and I’ve met very few owners who would not do so if they understand the problem and are in a position to do so.

Once we identify and quantify the lack of progress, we can determine the root cause and identify a trend, if one is developing. We cannot do this if we simply look at another Gantt Chart pdf and look at the scheduled finish date for the project.

The owner needs to understand what work is slipping and why and this should be discussed with all parties to find a solution to keep the project safe. But this does not happen if the owner is not fully informed of progress slippage for Critical and Near-Critical work.

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Network Logic Progress Update Information for Owners.

As a continuation of my previous posts, I will continue to discuss some of the important progress update items we review and analyze.

I will now discuss the process of verifying the network logic is complete.

When the contractor adds the actual Start and Finish Date and expected Finish Date data to the schedule update, the new scheduled completion date if most often not what any of us want. Usually, there has been slippage in work progress in an area that must be addressed.

The contractor will investigate and add resources or increase hours for that work or re-sequence the work in the most cost-effective manner possible to recover any lost time. The contractor is usually required to convey that plan to you with the schedule update narrative. However, this is seldom the complete picture…..

Quite simply, when there are logic changes made, it is easy to create missing logic such as an activity with one successor with only a Start-to-Start, SS relationship. This leaves this logic open as the finish of the activity does not drive the start or finish of any other work.

Reverse logic can also be inadvertently created. This is when an activity has only a predecessor with a Finish-to-Finish, FF relationship and a successor with an SS relationship. With this condition, any increase in duration of this activity will actually pull the successor back in time. Not realistic…

Those are a couple of the basic items we look at.

It is simple enough to “recover” time on the update by shortening a duration here or there and perhaps changing some Finish-to-Start, FS logic to Start-to-Start, SS logic. If the contractor can actually commit to the production necessary to achieve the shorter duration, great. If the work can actually be completed with the new logic, that’s good too.

The means and methods of how the contract plans to execute the project is really only of concern to us if it is blatantly clear it is not achievable. This is only my humble opinion. We won’t delve into construction contract law in my posts. I’m not qualified.

However, the schedule specifications and schedule best practices have been developed to provide a means of maintaining a valid schedule. We can argue means and methods of the execution, but the requirements for the schedule provide us with the tools to manage the schedule update process correctly and keep a valid schedule in place each period for managing the work and potential delays and changes.

That said, we run filters and programs that provide us with the list of items changed between schedules. This lets us know what changed, but not necessarily why. This is why the schedule update narrative is important. It is the contractor’s tool to convey this information to the owner.

If we find several relationship changes to activities which were on the previous period schedule update Critical Path for Near Critical Path(s), we need to know why these logic revisions where made. Was it to better sequence the work based on input from the subcontractor’s performing the work? Is it an attempt to shift the Critical Path? Is it masking a lack of performance for work on the Critical Path? Same holds true for the Near Critical Path(s).

Often times, the contractor is able to better plan the work immediately in front of them. This involves minor revisions to the logic and/or durations. Any changes to these items and other items such as calendars and resources should be included in the schedule update narrative and explained.

It’s easy to spot the poor performance trend when you have an Owner’s scheduler review each update period. This provides an early flag for the owner and the contractor, so the necessary actions can be taken to recover sooner rather than later……

I’m sure many of you have comments or additional insight into this subject. Please share!

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP

Construction Scheduling. Total Float Values and Calendars.

Do you ever look at a schedule and wonder why a series of related activities will have different Total Float values? Perhaps the activities on the Critical (Longest) Path?

It just makes sense that the activities in the same work path would have the same Total Float value.

However, when your contractor develops the project baseline schedule, they develop the various Activity Calendars for the project. There may be a 7-Day Work Week Calendar for Milestone Activities, Level of Effort Activities, and fabrication or delivery activities. There may be a 5-Day Work Week with Holidays Calendar for work planned for normal work days but not on holidays. There may be a weather calendar with specific days set as non-work days to allow for the anticipated normal weather impact days.

Each calendar will have a different action on the Total Float value because each calendar only allows the work to be scheduled on the work days for that specific calendar. This, in turn, determines the Total Float value.

This is why the Milestone Activities on the Critical Path may have a value of -7 days and the activities on the 5-Day Work Week Calendar may have a value of -5 days.  The 5-Day Work Week Calendar doesn’t take the weekend non-work days into account with the calculation. The total Float value for the activities assigned to a weather calendar would also be different.

This is also why a set period impact to the schedule, such as 30-day delay in receiving direction to start work on a work package could have a larger delay to the contract completion. A 30 Calendar Day impact can push the work over non-work periods such as holidays and weather resulting in a 35 Calendar Day impact to the contract Completion Date. This must be accounted for in the Time Impact Analysis so the party not responsible for the delay is not forced to absorb this variance.

The bottom line is: Don’t let Total Float values determine what is critical, let the schedule software do that by using the Critical Path definition of Critical = Longest Path. Using the Total Float values is valid for many things, but determining your Critical Path isn’t one of them. If you have more than one calendar for the activities, there will be differences in the Total Float values.

I know many of you can offer additional comments and recommendations. I welcome your comments and input. My goal, as always, is to help our industry and help the projects we support….

I’d love to hear what you think!

Please visit https://conschmanservices.com to learn more about Construction and Schedule Management Services, LLC

Please visit my LinkedIn account to learn more about me.

Please visit my “The Blue Book” ProView.

Paul Epperson CCM, PMP, PSP, PMI-SP