How to Perform a Time Impact Analysis in Construction

Time Impact Analysis

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A Time Impact Analysis is a method used to determine the extent of impact from potential delay in the construction process. Time Impact Analysis could be one of the preferred methods to promote negotiation and later agreements on delay claims. Time impact analysis is done using existing schedules, analyzed with all related input entered into the schedule to demonstrate the reason or possible effects on schedule.​

Time Impact Analysis is usually performed by a project scheduler and can be used on the vast majority of construction projects. This schedule analysis method involves the insertion or addition of activities indicating delays or changes into an updated schedule representing progress up to the point when a delay event occurred to determine the impact of those delay activities.

Time Impact Analysis Expectations

A Time impact analysis will be applied to forecast the construction process and analyze what is going on and what the outcome will be. It requires a CPM schedule that is able to show the pure CPM calculation differences between a schedule that does not include a delay and one that does include an activity modeling a delay. A time impact analysis is required to calculate with a standard method the results of the actual project delay.

The analysis is not the project reality simulation, it is intended to understand the time impact caused by a single event or series of events, and how they will impact the project schedule. It is a great tool for projects that are currently ongoing and will present a real-time idea of how the contract adjustment is required.

The final result of the time impact analysis must be presented shortly after completion to the contractor; otherwise, he might present an additional time extension claim of constructive acceleration. It is the best technique for determining the amount of Extension of Time that the Contractor should have been granted at the time that an excusable risk occurred.

Time Impact Analysis Uses

Time impact analyses are used on these occasions:

  1. When the contractor has not been able to provide remediation instructions and it is not able to redeploy his workforce.
  2. . Time impact analysis is an excellent tool to measure actual delays in events that are undergoing construction activities.
  3. The analysis could be used when delays are already being expected due to external or internal circumstances.
  4. Time impact analyses are used to model delays in short or simple construction activities. If delays are longer than usual additional methods and tools must be used in conjunction with the TIA.

    Time Impact Analysis: When to Avoid It

    Time impact analysis should not be used or will not present the best results when:

    1. It must be avoided if your actual project schedules have not been updated. TIA will not present a real outcome when data input on the analysis has not been updated with real data from the construction activities.
    2. Work plans based upon resource considerations are more easily adjusted without detriment to the project completion or planned expenses than those based upon physical constraints.
    3. Time impact analysis should be avoided when mitigation work has already been started. If the constructions schedule has been altered, the less effective the modeling of the delay will be.

      Time Impact Analysis Procedure

      A time impact analysis requires the following steps:

      1. The delay should be described as simply as possible with the fewest number of activities reflecting the project delay.
      2. Select the schedule to impact. The schedule should be latest updated schedule for the project.
      3. Add the impact activities and make the necessary adjustments to project schedule.
      4. Recompute the CPM and note a change in the project completion date.
      5. Determine the amount of project delay.
      6. Determine the actual dates of the delay using the original schedule

      Time Impact Analysis Checklist

      When performing a time impact analysis be sure to:

      1. Study and understand the scope of the directed change or analyze the extent of the delay being found.
      2. It is important to analyze all documents, field directions, contract clauses, drawings, orders, specifications and conditions that could exert any kind of influence on the expected delay.
      3. Identify and describe the condition encountered before performing the time impact analysis.
      4. Identify all related construction activities that are or could be affected by the expected delay.
      5. After a complete analysis of the construction schedule, determine all related dates, start, duration and finish, for all affected activities.
      1. Prepare a complete set of documents that define when the delay started, what actions took place at that moment, and demonstrate the effects of the delay on the actual updated schedule and how the remaining activities should be altered, if required, to complete the project on time.
      2. The time impact analysis could present you with the overall schedule result incorporating drawings, contract requirements, and any type of document that support final conclusions. It is important to highlight extraordinary measures required to bring the project back on schedule.
      1. Be certain that actual delays are a result of the change directive or delay, not from a non-excusable cause.