Lessons in delay analysis

Many readers will be familiar with the SCL Delay and Disruption Protocol, now in its second edition. Among other things, the protocol sets out six commonly used forms of delay analysis in construction disputes. A recent decision of an Australian court has commented on two of these methodologies and the significance of the protocol generally in relation to delay analysis.  

The two methods considered by the court were “as-planned v as-built windows analysis” and “collapsed as-built analysis”. In the former, chunks of time or “windows” are taken (usually based on milestones or fixed periods of time) and as-planned and as-built programme records are considered to identify the critical path during the relevant window and the amount of delay incurred. This delay is then sought to be attributed to causes during the period through a close review of the project records. 

A collapsed as-built analysis requires a detailed logic-linked as-built programme. Once this has been developed, the programme is “collapsed” by identifying delaying events and removing them from the programme to provide a hypothesis as to the delay caused by those events. The use of programming software allows the as-built programme to be easily probed in this way. The method is heavily dependent on the logic-links included when preparing the as-built programme. 

The case before the Australian court, White Constructions Pty Ltd vs PBS Holdings Pty Ltd, involved a developer  of a housing development near Sydney (White). It engaged a sewer designer for the development (IWS) and a water servicing co-ordinator (PBS). Considerable delay was suffered in having IWS’s sewer design approved by Sydney Water (the relevant public authority). White alleged that IWS’s original design and PBS’s supervision of it had been flawed and that the resulting delays in obtaining approval for a revised design caused knock-on delays to the development as a whole of more than seven months. 

White submitted evidence from a delay expert, which supported its delay case and relied on an as-planned vs as-built windows analysis. IWS submitted a report from a delay expert claiming that, at most, only 19 days of delay were caused. IWS’s expert relied on a collapsed as-built analysis. Both of the experts criticised the other’s choice of methodology. 

The New South Wales Supreme Court accepted the criticisms made by both experts as to the other’s approach. Some of the key criticisms were:

• The logic-links in the as-built programme prepared by IWS’s expert were not sustainable 
• IWS’s collapsed as-built analysis was too simplistic and obscured the inefficient performance of work caused by the delayed sewer approvals 
• The windows analysis prepared by White’s expert had not taken into account certain delays unrelated to the sewer design and had assumed unjustifiable as-built logic links 
• The windows analysis was also flawed because it “assumes causation rather than identifies actual evidence of it”. 

The court therefore rejected the evidence of both experts and proceeded to appoint its own expert. On the advice of that expert, the approach favoured by the court was an open-textured one, unbounded by any specific methodology. 

The court considered that “[…] the court should apply the common law common sense approach to causation […] The only appropriate method is to determine the matter by paying close attention to the facts, and assessing whether White has proved, on the probabilities, that delay in the [sewer design] delayed the project as a whole and, if so, by how much.”

The court also declined to give any special standing to protocol: “for the purpose of any particular case, the fact that a method appears in the protocol does not give it any standing, and the fact that a method, which is otherwise logical or rational, but does not appear in the protocol, does not deny it standing”.

White’s delay case was dismissed on the basis that significant gaps in the evidence existed, meaning there was insufficient proof of the specific delaying effects of the revised sewer design. 

Although a decision of an Australian court, the comments made in this case as to the two delay analysis methodologies referred to are likely to be of broader relevance to construction disputes elsewhere in the world. Some of the criticisms made of those methodologies could be said to be of general application, while others may be the result of poor records. The overall impression from the judgment is that the court considered the experts to be advancing methodology at the expense of evidence. 

The court’s decision also highlights the importance of delay experts attempting to agree on an appropriate methodology at the outset. Debates over methodology can take on a life of their own and distract from a focus on important factual issues. The court in this case felt unable to support either of the positions adopted and was forced to do its best with a broad, commonsense approach. 

Aidan Steensma is counsel specialising in infrastructure, construction and energy disputes at CMS Cameron McKenna Nabarro Olswang