You have a baseline schedule, with a few periodic updates completed, and now you need to make a revision to the schedule to dramatically re-sequence work, add/delete work to/from the project, or provide a required “Recovery Schedule”. What do you do?
This is one of the more difficult schedule management tasks. In some ways, it is almost more difficult than creating the baseline schedule.
Depending on the amount of time you need to “recover”, you will need to find the root causation for the schedule slippage and get that under control. This could mean anything from having the party responsible for the slippage work additional hours to maintain the daily scheduled productivity, adding resources to increase the daily scheduled productivity, or resequencing of work to mitigate the lack of daily scheduled productivity or model concurrent work.
Next you will need to develop the most cost-effective means of accelerating work on the current longest path. This is tricky. Your schedule may have a near critical path which is very close to the scheduled longest path. As you shave days off the longest path, it will shift to the near critical path making that path the longest path. You will need to keep working at accelerating activities on the longest path, as it shifts until you reach the point of “recovery”.
That’s the easy part.
Now you have to obtain support for this plan from the project team. Subcontractors have to agree to provide what is needed to achieve this revised plan. Deliveries must be verified. Resource availability must be verified. There is probably additional cost involved. This must be managed a well.
In summary, any “recovery plan” will most likely involve concurrent work and/or acceleration of work. In any case, submitting a “recovery schedule” without the support of the project team for execution of the revised plan is a disservice to the owner, the project team and the project. You must be able to gain the commitment of the project team.
Schedule management includes many tasks and processes. Developing the “recovery schedule” is one of the more difficult tasks. The Project Manager should always be intimately involved with the planning of the revised work plan and “buy-in” from the project team is necessary for the successful execution of the “recovery plan”.
You may be able to manage the development of the recovery schedule without any problems.
You have created your project’s baseline schedule and now you are starting the schedule management phase of the project. What do you do?
If you have not done so already, you need to establish a “schedule log”. I like to start my schedule log when I start development of the baseline schedule. This allows me to track my revisions and reasons for making them. The schedule log provides you with historic data for each revision or update to the schedule. Very handy.
If you have not done so already, set up schedule layouts and filters you plan to use. I also set these up during me schedule development, but often times the owner decides they want to use something other than what the schedule specifications require.
Each periodic update, save your schedule with progress only. This allows you to see what the progress update did to your schedule, save this snapshot. Then make any revisions to correct out-of-sequence, OOS relationships and model the revised plan to finish on schedule. You now have your updated and revised schedule ready for use.
Update the schedule periodically. Compare your progress with the most current previously accepted schedule and the baseline schedule. Look at how you’re tracking, how your actual durations are comparing to your scheduled original durations, and how your work sequence is actually progressing. Identify problem areas and trends and develop corrective action to recover time lost.
After you update the progress for your schedule, revise the schedule update to reflect your actual plan for execution. This doesn’t mean a complete change of sequence or addition of new work. This is simply to model adjustments you are going to need to make to maintain the scheduled completion date.
Major revisions to the schedule to dramatically re-sequence work or add/delete large pieces of work are handled differently. This will be part of a future post.
Managing the simple month to month schedule update process is pretty straightforward. Correcting the OOS is more involved and care should be taken to follow best practices. This is all part of the basic schedule management process.
You are working with a construction scheduling consultant and they use terms you’ve heard before, but you’re not 100% sure you really understand what they mean. More importantly, you’re not sure how they affect the schedule.
Typically, the data date is the end of the month, but I’ve seen it be the 15th and the 25th. Each schedule specification is different based on the owner’s requirements for reporting. Note: MS Project uses the term “Status Date”.
This is the date that all progress should be updated for progress up to. Everything after the data date is the pan to execute the remaining project activities. There should never be work in progress or incomplete with dates prior to the data date. I’ve seen this all too often with schedules run in MS Project because the person doing the schedule update does not understand this concept and how to adjust the settings to force incomplete work to move to the status date. It’s a simple fix for an experienced scheduler. Always look at your schedules and know the data date and verify all work prior to the data date is complete and all work after the data date shows no progress. Think of the data date as the starting off point for the rest of your project…. This is a necessary practice for construction scheduling.
What is “OOS” and why do I care?
OOS or Out-of-Sequence is simply a way of saying that work actually completed did not progress as scheduled.
Typically, this involves an activity that was scheduled to start immediately after the finish of it’s “predecessor” having actually started prior to it’s “predecessor” finishing. Other reasons may be work progressing much differently than scheduled or work being suspended for whatever reason.
Why do you care? You care because this logic is still driving any “successor” activities and is not correct based on how you actually completed the work. It affects all downstream work logically tied to the finish of the OOS work and does not model the remaining work correctly.
This can affect change order fragnet insertions, not produce correct total float values, and does not provide you with an accurate as-built schedule. Best practice is to correct the logic for OOS work immediately after updating the progress each period update. Most schedule consultants do this, but many do not and most PM’s and Superintendents do not. Many owners are not aware of the need to correct OOS relationships and do not require or enforce this practice. This is unfortunate. There are times y0u can leave some OOS relationships in place, but absolutely OOS work on the longest path or near critical path should be correct. Most construction scheduling consultants correct OOS relationships each schedule update.
What are “Lags” and why do I care?
Lags are like invisible activities added to the schedule; which typically separate start dates of successor activities by a set amount.
Depending on which calendars are assigned and the relationship selected, a current activity’s successor activity will start immediately after the finish of the current activity, if the relationship is a Finish-to-Start, FS relationship. Adding a lag of 3 to this relationship would force the start of the successor to wait 3 work periods until starting. Sometimes this is used for concrete curing time…… I prefer to use an activity for this so the time is transparent.
But typically, lags are used with Start-to –Start, SS relationships to allow work to be schedule concurrently. The lag forces the successor activity to wait set number of work periods after the start of the predecessor activity starts before starting. This models a plan to start one piece of work and then start successive work a set duration later. Such as finishing gypsum board wall sheathing before the entire area covered by the activity to hang the gypsum wallboard has completed. This is fine if this represents your plan to execute this work. Unfortunately, this is also how most PM’s and Superintendents choose to get the scheduled finish date back on time after the periodic update shows the project is behind schedule. This is still fine if the work can actually be executed this way, and it is the actual plan to “recover” lost time. It is just so darn easy to do, that many times it is used to appease the owner only and no plan is used to actually accomplish the work concurrently. This happens when the schedule is only part of the invoice process, and not an integral part of the project management process.
Don’t be afraid of lags, but the use of lags should be judicious and justifiable. There are many ways to model the logic to reduce the number of lags used. Typically, breaking the work into smaller pieces will allow the work to be scheduled without the use of lags.
Negative lags are bad idea and should be avoided or disallowed. There are many ways to make the logic work without the use of negative lags. Most schedule consultants stay away from negative lags.
MS Project shows lags and relationship types other than Finish-to-Start, FS in the predecessor and successor columns. Primavera P6 does not. Although it is not always easy to understand the effect a lag is having on the schedule, you should always be aware of their usage and understand the effect they have on the project schedule.
Now that you’ve engaged your planning and schedule professional, what will you need to provide this consultant for them to be able to successfully provide the schedule support services you need?
Before any schedule review can begin…..
First, they need to understand the project. To do this, they need to learn the basic scope of the project. They will need the IFB or RFP docs with addendums, the successful contractor’s proposal, the award documents (if the contract is already awarded), your reporting requirements or preferences, and a list of stakeholders.
They need to understand what the schedule requirements are for your specific project. (Hopefully, you require a critical path method (CPM) schedule with specific activity coding, calendar, schedule and calculation requirements). The schedule consultant needs to know what the successful contractor proposed and any exceptions they may have included. The schedule consultant needs to know what your reporting preferences are, in addition to whatever requirements you have provided. The schedule consultant needs to know who the project stakeholders are and how you want their reporting formatted, or if you want stakeholders getting reports directly from any scheduling consultants at all.
All planning and scheduling consultants must develop a basic idea of the project work breakdown structure (WBS) and organizational breakdown structure (OBS) the contractor will likely develop. This is basically an organized list of the project deliverables broken down into work packages and a list of individuals or companies from which to assign a responsible party for each package. This is necessary for the review of the contractor’s schedule development and validation that the entire project scope is included by the contractor.
Baseline Schedule Development….
The contractor will develop a preliminary or baseline schedule, (depending on the contract requirements…), and submit for your review. This needs to be forwarded to the schedule consultant immediately. Scheduling consultants will review the WBS & OBS for completeness and organization. Scheduling consultants will then verify calendars have been set up and assigned. They will review resource and cost loading, (If these required by the contract). They will verify schedule and calculation settings meet the contract requirements. They will review several schedule metrics and develop review comments. Scheduling consultants will verify required milestones are included and review the use of activity constraints. Scheduling consultants will review the proposed work sequence for reasonableness. They will review activity durations for reasonableness and note anomalies. Scheduling consultants will verify the schedule period of performance meets the contract requirements. They will then create reports and review comments for your use.
The baseline development process may require a couple of passes to get to an acceptable project baseline schedule. Once this is completed, the schedule consultant will set up schedule performance metrics to use for measuring the contractor’s progress against the baseline and subsequent accepted schedule updates.
This will provide you with a project baseline schedule, (and hopefully it is a CPM baseline schedule), based on the contractor’s plan to execute the project, of which you can have confidence in. You can use this schedule with a high degree of confidence, (If you have a CPM schedule).
Managing Updates, revisions, change orders and recovery schedules…
The planning and schedule professional will be able to review periodic schedule updates provided by the contractor and compare the progress against the baseline schedule or the most recently accepted update and identify delays in the contractors work and trends in work areas which could potentially delay work at a later date. They will do so by comparing the performance for the current period schedule update against the previously accepted schedule update and the baseline schedule and then analyzing changes the contractor makes to the schedule update. This is much easier if the contractor updates the schedule in a two-part process. First the contractor updates the progress only, with no revisions, and submits for review. This schedule will most likely include out-of-sequence work and total float values which are not acceptable. That’s fine, we only want to see what updating the progress did. Now the contractor can make schedule revisions as necessary to correct out-of-sequence work and model their plan to complete the remaining scheduled work. This is the schedule they will submit, and you will accept based on the review and comments of the schedule consultant.
If you need to make changes or additions to the contract, you will, of course, request pricing from the contractor and negotiate this additional work or change in scope. The contractor should also be including a request for additional contract time to incorporate this additional work or change in scope. Or they should be stating that no time extension is needed or requested. Prior to sending the contractor your request for change pricing, you should have your schedule consultant review the change and the potential impact to the currently accepted schedule. This involves the schedule consultant creating a “fragnet” or subnet of schedule activities to model the change order work and inserting it into the most recently accepted schedule to analyze the impact to this schedule. (This is the same as having an owner’s independent estimate completed prior to receiving the change order proposal from the contractor). The schedule consultant will then compare the contractors request for time to the estimate created and develop a contemporaneous Time Impact Analysis. This is the best way to manage potential time extension claims. Address them now and get them negotiated as part of the current change order. The schedule consultant will review the contractor’s “fragnet” for reasonableness and report on the impact to the project’s current critical path. This is what determines the change in contract duration, (if you have a CPM schedule).
If your contractor falls behind in their progress, based on the most current accepted schedule, you will most likely require them to develop and submit a recovery schedule. This schedule will need to be reviewed by your schedule consultant and also be accompanied by a narrative defining how the contractor plans to implement the recovery. Be it through additional work hours, an increase in resources, and prefabrication of assemblies…… The schedule consultant will look at the plan for recovery and compare proposed durations against historical project performance and production rates and verify the plan meets the required finish date. You will want to be involved in this review. If it cannot be determined that the contractor can actually implement the plan for recovery or the contractor’s plan is just not reasonable, there needs to be a discussion with the contractor. Your schedule consultant can provide this analysis and reporting to support your discussion.
The owner absolutely needs a planning and schedule professional on their team to act as their advocate for the project schedule development and management. Not using professional planning and scheduling consultants is kind of like just accepting any price proposal the contractor provides with a change order request or any periodic invoice amount the contractor submits without any verification of validity by a competent team member. You would not follow a process like that for cost management. Unless you have a competent team member to validate all schedule actions, you’re not really managing your project schedule…..
I realize this is a simplistic view of the entire schedule oversight process. This is intended for use by small CMa’s and owners that do not have a planning and schedule professional on their team or completely understand the necessity of CPM schedule and professional schedule oversight.
You have an approved baseline project schedule and you are working your plan. That is great. You are utilizing a valid tool to proactively managing your project. But, you still need to monitor the actual work progress and take corrective action as necessary to maintain your scheduled plan to execute the project. This is an important part of the construction project scheduling process.
Best practice, for most projects, is to update the project schedule progress weekly. This allows you early identification of schedule slippage. Most contracts require monthly schedule updating and reporting to the owner or Construction Manager Agent, CMa. You should really do both. Complete weekly progress updates for your own use and provide monthly reporting as required.
What progress information do you need to provide the planning and schedule professional for the CPM schedule update process?
Before you begin the update process, the frequency of reporting and report requirements needs to be established and planned for in the CPM schedule development process. (Which is part of the master construction project scheduling process).
The planning and schedule professional will require several key pieces of information for each activity in order to properly update the schedule progress.
They need the data date, (as-of date) for the update. (This is probably specified in the contract documents).
They need the actual start date for each activity started. (This should be recorded in your daily reports by activity number. It makes it much easier to remember the information).
They need the actual finish date for each activity completed. (Again – Daily Reports)
They need the physical percent complete, (% of actual work accomplished) for each activity. (This is a judgment call based on measurable work completed. Like the number of windows installed against the total quantity required for the activity).
They need the estimated finish date for any activity underway. (This is a judgment call based on production to date and expected production to complete).
These five simple pieces of information, when assigned to each activity, will allow your schedule consultant to produce a schedule which provides new calculated start and finish dates for all remaining work based on the relationships assigned during the CPM schedule development process and the progress to-date with the expected production rates of in-progress activities.
Note: It is a good idea to keep a copy of this updated only schedule for future reference.
This is a great time to analyze where you’re at on your schedule and look at any corrective action necessary to “get back on schedule”. But before you do this, you need to look at any work you’ve executed out-of-sequence to the plan. Perhaps you were able to start an activity prior to the completion of the activity’s predecessor. That’s OK. You should make any schedule revisions necessary to correct any out-of-sequence logic so the schedule progress matches your as-built progress. This is a good practice and will help with any revisions you need to now make to get “back on schedule”.
Note: Rarely is the project “on schedule” after an update. At a minimum, there is likely to be out-of-sequence work even if you have maintained the scheduled finish date.
Now you can make revisions to your planned logic and/or durations to reflect your plan of execution for the remaining work. This should be based on actual, corrective action you intend to take. You need to provide this information to the planning and schedule professional. This will most likely be an iterative process you go through with your schedule consultant.
Once you’ve completed the revision process to “get back on schedule”, you have an updated schedule which can be submitted in support of your monthly invoicing or used in-house. If you contract requires your schedule to be cost loaded, you should verify the dollar values calculated for each period update match the physical percent complete, (actual work in place or whatever your contract requirements allow). Many contracts which require the project schedule to be cost loaded base the monthly invoicing on this value, rolled up for each activity.
This “schedule update” is the schedule any future work will be measured against for period performance measurement. (In addition to measuring against the most recent approved baseline schedule). This is also the schedule any new change orders will be based on.
Note: It is imperative you maintain an accurate schedule throughout the project. Without an accurate updated CPM schedule, you will struggle to substantiate any delay claims or requests for time for change orders.
There is more detail which can be measured when updating the schedule progress such as units completed and labor hours expended. These are great to measure and track. But I consider these more advanced items than the typical small to medium size general contractor will have the resources to accurately forecast or manage on a daily basis.
Revising the schedule for delays or change orders is another topic. Developing the projects’ CPM baseline scheduleand managing the periodic CPM schedule update process are basic building blocks of schedule management and the construction project scheduling process.