Time is one of the most valuable commodities in the construction industry, and there are a host of events that could change the completion date. That means construction managers and contractors must be able to anticipate how any given event will affect the rest of the timeline. One of the most accurate methods for making such a determination is via time impact analysis.
What is a Time Impact Analysis?
A time impact analysis is a method used to determine the extent of the impact that a delay or change order will have on the overall project timeline. This is a “forward-looking” analysis since it focuses on the impact of events that have already occurred or are presently occurring.
A time impact analysis will be most effective for projects using the critical path method for scheduling. The time impact analysis focuses on a specific event, by providing a snapshot of the impact event and integrating it into the project’s current critical path.
Speaking of the Critical Path Method…
The Critical Path Method Creates More Efficient Construction Schedules
Why is Performing a Time Impact Analysis Important?
Any time something impacts the project schedule – like a change order or directive, a defect, or some other delay – it’s important to update the overall project schedule to account for changes. It’s not always easy to calculate exactly how much time one of these events will affect the project timeline, though.
A time impact analysis provides the opportunity to really dig into the work that’s required due to some event that changes the project schedule. By performing the analysis, it will be easier to accurately plan for the remainder of the project – rather than just slapping at it or going with the flow.
How to Perform a Time Impact Analysis
Properly performing a time impact analysis requires attention to detail and can be time-consuming, but it will produce the most accurate results. The following is a simplified overview of how a true time impact analysis works.
Identify the Impact Event
Impact events can be delays, change orders, differing site conditions, or any other event that may impact the overall project completion date. The first step is to collect the documentation and identify what additional activities are required to correct the impact. This should show the sequence of activities and time it will take to finish the additional work required.
This is often called building a “fragnet” (short for “fragmented network”). You can consider a fragnet a miniature critical path method schedule for whatever is impacting the project schedule. By identifying how the change will be undertaken, it’s easy to determine how much time the change will take, and how that change will affect the overall schedule.
Identify the Current Project Schedule
Project schedules are changing all the time. Select the most current schedule available. The time impact analysis will fail if using an outdated version of the schedule.
Add the New Work to the Schedule and Analyze the Impact
The next step is to plug the fragnet into the project schedule. Again, “fragnet” simply refers to the mini-critical path which represents what work is required due to the event that’s changing the project schedule. Basically, it’s just a mini-schedule for the new work.
This requires identifying any logical relationships between activities. If one task will depend on some other task first being completed, that should be noted. Once the fragnet is correctly inserted into the schedule, be sure that the activities still follow a logical path. If there are any scheduling issues, make any necessary adjustments and document the changes.
Recalculate the Critical Path
Finally, its time to analyze what sort of impact the event had on the overall project. Determine whether the event had any impact on the critical path or any interim milestones. Compare the original schedule to the impacted schedule to determine if and how long the contract completion date has been affected.
Analyzing the Impact of a Change or Delay Helps Avoid Disputes
The more precisely a time impact analysis is performed, the more accurately the schedule can be adjusted. At the same time, performing a detailed, in-depth analysis might not be necessary for every job. Sometimes, simply putting critical thought into exactly how a change will affect the project schedule might be enough.
The most important thing is setting and communicating realistic expectations regarding the project schedule.
Project delays are one of the leading causes of construction disputes. The impact event may be owner demands, it could be a weather delay, or it may even be due to faulty project specs. Regardless of the cause for the delay, it’s crucial to have a solid plan for moving forward. By performing a time impact analysis, even an informal one, it’s easier to anticipate – and therefore communicate – how certain events will impact the overall project schedule.
Don’t be a hero! All too often, aggressive schedules are created in order to keep an owner happy. But, by creating an honest and accurate new project schedule, managers and contractors can manage expectations at a realistic level.
Software Can Help Perform an Accurate Time Impact Analysis
Software exists to lighten the load of construction businesses on a number of different fronts. Construction scheduling is one area that can greatly benefit from the use of software – especially for large and/or complex jobs.
If some of the steps under the Performing a Time Impact Analysis section above sounded confusing, or if there are too many moving parts on the job to keep track of, looking to software can really help. Here’s a breakdown of top construction scheduling software: Construction Scheduling Software Reviews.
Bottom Line
Time is money. When issues arise, playing the good soldier and carrying on as planned can be a dangerous proposition. Failure to properly adjust the project schedule is a big deal, and it can lead to costly delays and disputes. It can also leave the door open to a number of potential requests for additional time and money, not to mention the manhours wasted resequencing activities and subcontractors. Identifying and responding to any unanticipated events is an essential element of proper project management.
Additional Resources
- Construction Schedule | Tools for Completing Your Project On Time
- How to Request an Extension of Time | Construction Notices
- Understanding Acceleration Claims in Construction
- Construction Document Management Presents Unique Challenges
