Understanding Impacted As-Planned Analysis
Impacted as-planned analysis is a prospective delay analysis methodology that adds delay events to the baseline schedule to show their theoretical impact on project completion. This additive approach demonstrates how specific events would affect the planned schedule, making it useful for evaluating potential impacts and supporting time extension requests. Effective construction scheduling software supports impacted as-planned analysis through schedule modeling capabilities.
The methodology uses the as-planned baseline as the analytical foundation, inserting delay events as additional activities or duration extensions to show their effect on planned completion. Your construction management software must maintain accurate baseline schedules that support meaningful impacted as-planned analysis.
When to Use Impacted As-Planned
Impacted as-planned analysis suits specific situations where its characteristics provide advantages. Your construction project management software should support this method when circumstances warrant.
Early project delays before significant progress changes the schedule favor impacted as-planned. When the as-planned schedule still reflects actual conditions, adding delay events shows their impact accurately.
Time extension requests during construction often use impacted as-planned to demonstrate anticipated impacts of current events. The methodology supports requests before delays fully manifest.
Simple delay situations with clear cause-and-effect relationships work well with impacted as-planned. Single events affecting identifiable activities can be analyzed straightforwardly. Your contractor scheduling software models these simple scenarios easily.
Methodology Steps
Impacted as-planned analysis follows a systematic process. Your best construction scheduling software should support each analytical step.
Begin with an accurate baseline schedule representing the original plan. This schedule should reflect actual planned logic, durations, and sequences at project start. Your construction scheduling software preserves baseline information.
Identify the delay event to be analyzed. What happened? When did it occur? Which activities were affected? Your construction management software captures event information.
Create a fragnet or modify activities to represent the delay impact. Add activities showing the delay period, extend affected durations, or modify logic as appropriate to the situation.
Insert the delay representation into the baseline schedule and recalculate. The difference between original planned completion and impacted completion represents the delay impact. Your construction project management software performs these calculations.
Creating Delay Fragnets
Delay events are typically modeled using fragnets—network fragments added to the baseline schedule. Your contractor scheduling software should support fragnet creation and insertion.
Fragnets include activities representing the delay period and its effects. A delivery delay might include waiting time, remobilization, and any make-up activities. Your best construction scheduling software supports detailed fragnet development.
Connect fragnets to affected activities with appropriate logic relationships. Only activities truly affected should have logic ties to the fragnet. Your construction scheduling software supports precise logic connections.
Document fragnet basis clearly. What events does the fragnet represent? How were durations determined? What assumptions were made? This documentation supports analysis credibility.
Critical Path Considerations
Impact on project completion depends on whether delayed activities are on the critical path. Your construction management software should show critical path status before and after delay insertion.
If delayed activities have float, delay may be absorbed without affecting completion. This result still matters—float consumption reduces future flexibility—but differs from completion extension.
Check whether delay insertion changes the critical path. Some delays shift criticality from one path to another. Your construction project management software displays these path changes.
Advantages of Impacted As-Planned
Impacted as-planned analysis provides advantages in appropriate situations. Your contractor scheduling software supports leveraging these advantages.
The methodology is straightforward to apply and explain. Adding delays to the baseline produces intuitive results that non-schedulers can understand. Your best construction scheduling software facilitates clear presentation.
Analysis can be performed early in delay events before full impact is known. This supports timely notice and decision-making. Your construction scheduling software enables prompt analysis.
The baseline schedule provides a stable reference point for analysis. Using the original plan as foundation avoids questions about schedule status accuracy at later dates.
Limitations and Criticisms
Impacted as-planned has recognized limitations that analysts should acknowledge. Your construction management software supports analysis while recognizing these limitations.
The methodology assumes the baseline schedule accurately represented how work would proceed. If the as-planned was unrealistic, analysis results are correspondingly unreliable.
Using only the baseline ignores how the project actually progressed. Actual sequences, productivity, and conditions may have differed significantly from plan, making theoretical impact analysis less meaningful.
Concurrent delays and contractor-caused delays aren't visible when analyzing only owner-caused delays against the baseline. The analysis may overstate owner responsibility by ignoring other delay causes.
Baseline Schedule Requirements
Meaningful impacted as-planned analysis requires a credible baseline schedule. Your construction project management software should ensure baseline validity.
The baseline should represent actual plans at contract start. Logic relationships, durations, and sequences should reflect how work was actually intended to proceed. Your contractor scheduling software preserves valid baselines.
Resource loading adds credibility. Schedules showing realistic resource allocation are more credible than those with unrealistic activity overlapping.
Baseline approval adds weight. If the owner approved the baseline, they implicitly accepted its validity as a planning tool.
Multiple Delay Analysis
Projects often involve multiple delay events requiring analysis. Your best construction scheduling software supports analyzing multiple delays.
Analyze events separately to show individual impacts. Each event's impact should be determinable independently. Your construction scheduling software supports event-by-event analysis.
Cumulative analysis shows combined effects. When multiple events contribute to total delay, cumulative analysis demonstrates their combined impact.
The order of delay insertion can affect results when events interact. Document analytical approach and consider whether order sensitivity affects conclusions.
Documentation Requirements
Thorough documentation supports credible impacted as-planned analysis. Your construction management software captures comprehensive documentation.
Document the baseline schedule used. What version? When was it developed? Was it approved? Your construction project management software maintains baseline documentation.
Document delay events analyzed. What happened? When? What activities were affected? How were impacts determined?
Document analytical methodology. How were fragnets developed? What assumptions were made? How were logic connections determined?
Document results clearly. What completion date results from adding delays? What is the calculated impact? Your contractor scheduling software generates results documentation.
Comparison with Other Methods
Impacted as-planned represents one of several delay analysis methodologies. Your best construction scheduling software should support method comparison.
Time impact analysis (TIA) uses schedule versions from when delays occurred rather than only the baseline. TIA captures evolving project conditions that impacted as-planned ignores.
Collapsed as-built works backward from actual completion, removing delays to determine their impact. This retrospective approach uses actual rather than theoretical performance.
As-planned vs. as-built compares baseline to actual completion without detailed delay analysis. This simple approach shows overall variance without establishing causation.
Best Practices for Impacted As-Planned
Use credible baseline schedules. Analysis is only as good as the baseline it's built upon. Verify baseline reasonableness before using for analysis. Your construction scheduling software supports baseline validation.
Model delays accurately. Use reasonable durations and appropriate logic connections. Avoid exaggerating impacts through optimistic or pessimistic assumptions.
Acknowledge methodology limitations. Where the as-planned may not represent how work would actually have proceeded, note this uncertainty. Your construction management software captures methodology notes.
Consider complementary analyses. Impacted as-planned may not tell the complete story; additional methods may provide fuller understanding.
Present results appropriately. Explain methodology to audiences who may not be scheduling experts; acknowledge limitations while presenting conclusions. Your construction project management software supports clear presentation.
Impacted as-planned analysis provides a straightforward method for demonstrating delay impacts early in events. When applied to appropriate situations using credible baselines and accurate delay modeling, the methodology supported by contractor scheduling software enables meaningful impact assessment.