ConstructionPro Week, Volume: 1 - Issue: 31 - 12/07/2012

Expert Offers Advice on Cumulative Impact Claims

By Steve Rizer


It would be wrong to assume that a large number of change orders translates into a successful cumulative impact claim, an expert in construction management advised professionals attending a WPL Publishing webinar, a recording of which recently was added to the ConstructionPro Network ( Download Library -- free of charge for members.


“Cumulative impact is oftentimes associated with lots and lots of changes on a project -- lots of change orders that have already been accepted or lots and lots of changes that the plaintiff thinks will eventually be attested to as legal change orders,” William Ibbs, group leader of the construction management program in the University of California at Berkeley’s Department of Civil and Environmental Engineering, told webinar attendees. "But just because you have lots of change orders doesn’t mean that you are necessarily eligible for a cumulative impact claim. A cumulative impact claim would be over and above the change orders that have already been paid for.”


Ibbs added it is important “to demonstrate those changes have had a synergistic impact on each other and a synergistic impact on [perhaps] the base contract work itself, so try to demonstrate cause and effect and try to demonstrate association through either the crews or the construction equipment that you’re using in performing the work.”


Also, it is beneficial to evaluate whether a contractor has “released his rights for subsequent cumulative impact, retrospective cumulative impact claims,” Ibbs said. “If he has not waived his rights by signing such release language, he will probably have an easier time successfully asserting a cumulative impact claim. [However,] even when a contractor has signed a change order that releases his rights, there are instances where those contractors have been able to unwind those waivers because they’ve been able to successfully demonstrate they could not have reasonably foreseen the ripple effects. So, be careful to evaluate that.”


During the webinar, Ibbs presented several different methods that can be used for estimating cumulative impact claims. “The slide [below] looks like a complicated chart, but it’s basically a flow chart that we have developed that you can walk your way through to try to identify which methods you might want to use in prosecuting or defending yourself against a cumulative impact claim. It’s going to be a function of the available information. It’s also going to be a function of the time and energy that you want to put into the dispute.”



The 90-minute webinar, entitled “Cumulative Impact 2012 -- Practical and Legal Considerations with Case Law Review,” additionally covered why productivity is important, factors affecting productivity, the symbolic impact of a change, court acceptance of cumulative impact, cumulative impact measurement, the Total Cost Approach, the Measured Mile Approach, and other areas.


Ibbs addressed a target audience of contractors, subcontractors, public and private owners, construction managers, schedulers, consultants, architects, and engineers involved in construction project management and administration.


For immediate access to the complete webinar (full audio and visual) -- as well as two dozen other construction-related webinars that are available for download -- sign up for a subscription to join WPL Publishing’s ConstructionPro Network complete training, education, and development resource for the construction industry at



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Posted by: Albertson - Thursday, January 16, 2014 7:20 PM


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