Effect then cause…but how?

Russell Bates


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In this article, Delay Expert and HKA Principal Russell Bates, explores the difficult area of identifying and assessing the possible impact of delay related causes in a retrospective analysis of events.


Delay analysis methodologies divide between consideration of assessing the critical path from either a prospective, contemporaneous or retrospective view.

In a prospective view, the causative issue is known, and the objective is to assess the impact (effect of that issue). It is referred to as a causation-based analysis.

In a contemporaneous or retrospective view of criticality, the approach is to establish the effect first, i.e., during the course of a project, when and for how long critical delay was experienced. This is referred to as an effect-based analysis.

Stage 1 – Incidence and Extent of Critical Delay

This is illustrated in the figure below which compares a planned timeline of 12 months (highlighted in green) for a building project with the actual timeline of 14 months (highlighted in blue). In this instance, the analyst concludes that all phases were completed in accordance with the planned intent with the exception of the cladding phase. The cladding phase took 4 months to complete as compared to the two months planned, resulting in a two-month critical delay to the project (highlighted in red). The conclusion is that there was a critical delay of 2 months to the progress of the cladding.

Figure 1: establishing the incidence and extent of critical delay

In this example, one would deduce that the cladding phase started in line with the planned date required, however, once the works were underway, delay began to accrue. The next step for the analyst is therefore to establish the causative issue(s) that gave rise to the critical delay to progress of the cladding.

I recall a discussion with a colleague who took the view that as delay analysts, our unique skill is in establishing which activities were critical and the extent of critical delay incurred. Establishing the causative issues should be relatively straight forward and be evident from factual records, or in the absence of such, witness testimony of those present on the project. In other words, you should not need a third-party consultant or expert to research this, it is something the client ought to be able to establish.

Nonetheless, in my experience establishing both cause and effect has been part of the service expected by clients and their legal advisors, often because:

  1. Inevitably, as a practising delay expert, I am appointed to take a retrospective view of events. Personnel turnover is a normal feature of any project, therefore those who might be most able to comment on particular issues are long gone.
  2. The appointment of a third party, whilst not having first-hand knowledge of the project, provides an independent view which is not coloured by project politics or ongoing arguments between the project participants. In effect, the delay expert provides a second opinion.

Nonetheless, based on my colleague’s view, when carrying out a delay analysis, either as a precursor to, or part of dispute related proceedings, one would expect that the most likely source of controversy would be in ascertaining the incidence and extent of critical delay regardless of cause.

Stage 2 – Forensic Investigation of Records – Access to Records

In so far as it describes various methodologies for delay analysis, the SCL Protocol[1]Society of Construction law Delay and Disruption Protocol, 2nd Edition 2017, Clause 11.6; subclauses (c) ‘Time Slice Analysis’, (d) ‘As-planned versus as built in windows’ and (e) … Continue reading identifies methodologies for establishing ‘effect’ in terms of criticality but when it comes to causation, merely states:

Thereafter, the analyst investigates the project records to determine what events might have caused the identified critical delay in each period.

In my experience this part of the analysis can be controversial and no less complicated to unravel. I recall a past project for a new office build where I was appointed to provide an expert opinion on behalf of the contractor on the incidence and extent of critical delay and the causes of critical delay.

When I first became involved, the issue that had been occupying the minds of the parties and had resulted in delay to the start of the internal fit out of the building, was having to carry out remedial works to fire protection. However, I concluded that the critical path was elsewhere, through a work sequence associated with external cladding.

So when I was asked to engage with the employer’s appointed a delay expert, my expectation was for there to be disagreement as to the course of the critical path through the project. To my astonishment he agreed with my assessment of criticality. However, any sense of relief was cut short because it transpired that he took a very different view as to the causes of delay to the external cladding.

Whilst the information provided to me indicated that the progress of on-site installations was being hampered by late issue of design information, my opposing expert concluded that delay was the result of manpower shortages by the cladding subcontractor, a matter which he said had been recorded in documents provided to him by his client.

It was therefore evident from our discussions that the identification of a specific cause, was predicated on what documents we had been given access to that in turn informed our understanding or perception of where the particular problem lay.

Why could such a circumstance arise?


1 Society of Construction law Delay and Disruption Protocol, 2nd Edition 2017, Clause 11.6; subclauses (c) ‘Time Slice Analysis’, (d) ‘As-planned versus as built in windows’ and (e) ‘Retrospective longest path’ analysis.

This publication presents the views, thoughts or opinions of the author and not necessarily those of HKA. Whilst we take every care to ensure the accuracy of this information at the time of publication, the content is not intended to deal with all aspects of the subject referred to, should not be relied upon and does not constitute advice of any kind. This publication is protected by copyright © 2024 HKA Global Ltd.


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