In this blog post, ICCP President, Paul Gibbons, examines thickening of preliminaries. This blog post is an excerpt of a question answered in our eleventh Construction Clinic session, which took place in June 2020. The entire webinar may be viewed on-demand on YouTube.

Question 1

Question: What is the meaning of thickening in a typical prolongation claim and how should it be claimed for?

Answer: The calculation of thickening deals with the impact of additional resources, plant and overhead which the Contractor or Sub-Contractor might be entitled to. Assessing thickening claims requires an understanding of the “planned” resources, plant, overhead and comparing this to the “actual” resources, plant and overhead. This would result in a planned versus actual histogram. It is best to keep the resource discipline separate so that it can be easily presented and assessed.

In simple terms, the ‘thickening’ is where you have more actual resources than that which you had planned to have. This might be caused by a number of things that would need to be tested, such as, i) the tender allowances might be wrong. If this is the case, then there would be no entitlement to “thickening”. Or the Contractor could have suffered additional work which required it to maintain a number of work fronts, which would lead it to thicken its resources.

As with all claims, thickening claims need to be linked to cause and effect and tied back to the periods of delay and to the records that have been contemporaneously maintained. Entitlement will flow from the Contract and costs calculations should be linked to the periods of thickening with any deductions being made if there is recovery already resulting from variations or claims for delay.

So, thickening is all about demonstrating what resources you had planned to have on-site against what you’ve actually had, with any entitlement being substantiated.

You can read more about the thickening of preliminaries in this blog post.The Institute of Construction Claims Practitioners also has a detailed paper on this subject. To request a copy, please send an email with your contact details to with “Preliminaries” in the subject line.

The question covered in this blog were answered by ICCP President, Paul Gibbons

If you would like to learn more about claims, check out our training partner, Claims Class.

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