Time Impact Analysis (TIA) is a forensic scheduling method that inserts a specific delay event into an accepted baseline schedule at the point in time it occurred, and measures the resulting push to the completion date. Resource and cost loading assign labor, equipment, and dollar value to each schedule activity so a CPM network reflects actual construction capacity, not just sequence and duration. HADVEN LLC prepares both from a project's own schedule files, correspondence, and cost records, built to the standard public agencies and owners expect during review.
What Time Impact Analysis Actually Measures
TIA is the most widely specified delay methodology because it evaluates one discrete event at a time, using the schedule logic that was already accepted before the event occurred. It answers a narrow, defensible question: given the approved baseline and the schedule updates leading up to a specific delay, how much did that one event push the completion date? It does not require rebuilding the entire project record, which is why many public agencies — including USACE, Caltrans, and various state DOTs — specify it as the required method in their contract scheduling provisions.
How a TIA Fragnet Actually Gets Built
Building a defensible TIA fragnet starts with isolating the delay event to its own activity or short sequence of activities, tied into the existing baseline logic at the exact point where the event occurred — not inserted earlier or later to maximize the calculated impact. The fragnet activity needs a duration supported by contemporaneous documentation: a weather day log, an RFI response delay, a differing site condition notice. Once the fragnet is tied in, the schedule is recalculated and the shift to the critical path completion date is measured directly, without adjusting any other activity's duration or logic to change the result.
An experienced reviewer checks each of these steps individually — where the fragnet ties in, what supports its duration, and whether anything else in the network was altered to produce the number being claimed. A TIA that fails any one of these checks gets rejected regardless of whether the underlying delay was real. For a comparison against other forensic methods, see our article on choosing between TIA, windows analysis, and collapsed as-built.
What Resource Loading and Cost Loading Actually Require
Resource loading assigns labor hours by trade, equipment hours by type, and a crew size assumption to every schedule activity, so the CPM network reflects actual construction capacity rather than just a duration estimate. Cost loading assigns a dollar value to each activity, tied to the contract's schedule of values, so the schedule can support progress payment applications as well as scheduling analysis. The two are related but distinct: a schedule can be cost loaded for billing purposes without being meaningfully resource loaded, and the difference matters once a delay dispute needs to show whether an event actually reduced crew productivity or only shifted paperwork dates.
What a Complete Resource Loading Data Set Looks Like
Effective resource loading needs three data inputs tied to every activity: labor hours by trade, equipment hours by type, and a crew size assumption consistent with how the work will actually be staffed. Many contractors resource-load a schedule once at baseline using generic unit-cost assumptions and never revisit it, which means the loading cannot answer the one question it exists to answer later. HADVEN builds resource loading from the crew and equipment data a contractor provides, and rebuilds it at each major update, so it stays usable as evidence if a dispute develops.
Why Public Agencies Specify TIA and Loaded Schedules
Agencies such as USACE, Caltrans, and most state DOTs specify TIA and resource- or cost-loaded schedules because they give the owner a documented basis for evaluating both progress and delay claims without relying on a contractor's word alone. A schedule built to this standard from the start survives review far more often than one adjusted retroactively once a dispute has already started.
What to Look For in a TIA and Resource Loading Consultant
- A fragnet built from the approved baseline logic, with the delay event isolated and documented
- Resource loading built from actual crew and equipment data, not generic unit-cost assumptions
- Familiarity with the specific agency's scheduling specification, since USACE, Caltrans, and state DOT requirements differ in format and review posture
- A clear explanation of how the analysis would hold up if it were challenged, not just whether it calculates correctly
Frequently Asked Questions
What is Time Impact Analysis in construction?
Time Impact Analysis (TIA) is a forensic scheduling method that inserts a specific delay event into an accepted baseline schedule at the point in time it occurred, and measures the resulting impact to the project's completion date. It is the most widely specified methodology for evaluating a single, discrete delay event.
What is a TIA and when is it used?
A TIA, or Time Impact Analysis, is used to evaluate how much a specific delay event — such as a differing site condition, an RFI delay, or an owner-caused change — pushed a construction project's completion date, using the schedule logic that was already in place before the event occurred.
What is cost loading in a CPM schedule?
Cost loading assigns a dollar value to each activity in a CPM schedule, tied to the contract's schedule of values, so the schedule can support progress payment applications in addition to sequencing and duration.
What is the difference between resource loading and cost loading?
Resource loading assigns labor hours by trade, equipment hours by type, and crew size to each schedule activity to reflect actual construction capacity. Cost loading assigns a dollar value to each activity for billing purposes. A schedule can be cost loaded without being meaningfully resource loaded, which matters once a delay dispute needs to evaluate productivity impact rather than just payment timing.
How does a delay fragnet get inserted into a schedule?
A delay fragnet is inserted by isolating the delay event to its own activity or short sequence of activities, tying it into the existing baseline logic at the exact point in time the event occurred, and supporting its duration with contemporaneous documentation before recalculating the schedule to measure the resulting impact.
Who provides Time Impact Analysis and resource loading services for construction projects?
HADVEN LLC provides Time Impact Analysis, resource loading, and cost loading services for construction projects, preparing fragnets and loaded schedules from a project's own schedule files, correspondence, and cost records for contractors, subcontractors, and public agencies.