• News
  • Contact Us

Change Order & Time Impact Evaluation


Ranging from complex construction projects to aerospace and defense programs, changes commonly occur. Exponent’s Construction Consulting professionals are familiar with all aspects of the change order process, from the initiation of the change—often through a Request for Information (RFI), to preparation, review, and evaluation to determine and quantify changes with respect to scope, price and time. Exponent can help sift through the project documentation to evaluate and establish the root cause of either the "directed" or "constructive" change, as well as determine the applicable direct and indirect cost associated with the change. Exponent has provided change order preparation and review services to general/prime contractors, subcontractors, owners, and design and construction management professionals. When a change to the project includes a time component, Exponent can assist in evaluating the change's impact to the project schedule and calculating the costs associated with delaying project completion.

Schedule Delay

To understand the true impact of a change to the project’s completion, change order analysis often requires introducing a delaying event into the schedule, using a fragnet. The fragnet is a scheduling element, which reflects the change’s additional scope, sequence of construction and relationship with other existing project activities. Insertion of the fragnet, into an accurate, working schedule, is done to prospectively forecast the time impact caused by the change to the project’s completion. This analysis is often called a contemporaneous Time Impact Analysis (TIA). The TIA can show how much delay the change will cause or caused to the project’s critical path, if any, and show exactly how the change impacts project completion. The result of this analysis is used to calculate the applicable time extension associated with the change. At this point, project stakeholders can evaluate whether a time extension should be granted, or mitigation efforts implemented in order to avoid or make up potential project delay.

Typical issues that might require schedule delay analysis include but are not limited to:

  • Change in scope of work
  • Right of way
  • Utility turnover
  • Differing site conditions
  • Force majeure, or “acts of God” events
  • Third party or customer-caused interference
  • Unusually severe weather
  • Untimely-Delivered and/or Defective Technical Data Packages (TDP)
  • Untimely-Delivered and/or Defective Buyer Furnished Equipment (BFE)

Change Order Impacts


Even if re-sequencing the schedule after the TIA mitigates project delay; there could still be additional impacts. Compression of the project schedule can lead to higher peak quantities of labor or equipment required for simultaneous use. Higher peak labor or equipment quantities may be greater than those originally anticipated by the contractor in its original baseline schedule, and subsequently requires additional resources as a result of the change.

Another potential impact from a change order is the associated loss of efficiency or loss of productivity. These types of inefficiencies are more likely to occur on changes with large quantity increases, or multiple changes. In certain instances, the large scope of changes, or the cumulative effect of many changes, may require the work force to work extended hours, longer work-week or in crowded site conditions. Individually and together, theses types of impact conditions may cause workers to work slower or less efficiently.

Dispute Resolution

When resolution of the issue requires an outside participant, Exponent Construction Consulting professionals can help prepare or review all aspects of the change order. Exponent can present its analysis to the opposing party and assist, as needed, should the claim require a more formal dispute resolution process such as mediation, arbitration, or trial.