A compromised starting schedule
A starting schedule that does not represent the relevant work or date can distort the modeled effect. Any adjustment needs a stated basis.
General contractors, subcontractors and construction managers

For contractors
A time impact analysis models the relationship between identified events and a schedule. The question being evaluated, the timing of the analysis and the schedule selected affect what the result represents.
The starting schedule, event model, assumptions and supporting information can affect interpretation of a modeled result. Those factors are considered in relation to the assigned questions.
An assignment may consider schedule selection, event logic and duration, calculated completion, float and other relevant events. The analytical approach and conclusions depend on the assignment, the project facts, the available records and the contract.
A time impact analysis may be considered in a prospective or retrospective context, depending on the question and the available records. The timing, schedule selection, assumptions and implementation affect how the analysis is interpreted.
Analysts may examine how the selected schedule relates to the work and the relevant point in time, including any adjustments and their supporting basis.
The activities, durations and relationships used to model an event can affect the result. Their support and sensitivity depend on the project facts and the model.
A calculated movement in completion is considered in the context of the model, assumptions, other events and assigned questions. Notice records, schedule submissions and responses can help explain how the modeled event was administered on the project.

Questions an assignment may address
Which schedule, time perspective and adjustments relate to the question being evaluated, and what supports their use?
Model the event as activities and logic reflecting what actually had to be done, tied into the schedule where the connection genuinely existed.
Run the calculation and observe the movement in the completion date, keeping the modeled change isolated from unrelated revisions.
State what the analysis shows, what it assumes, and what it does not address, including any other events in the same window.
Considerations and limitations
A starting schedule that does not represent the relevant work or date can distort the modeled effect. Any adjustment needs a stated basis.
Modeling assumptions and their supporting basis that are not explained in relation to the selected analysis.
Quietly absorbing other events in the window so a single impact figure appears cleaner than the record supports.
Prepare Time Impact Analysis (TIA)
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