Retrospective Delay Analysis in Construction Contracts
The many different methods of retrospective delay analysis can be divided into 3 groups: Non-critical path; static critical path; dynamic critical path. The 2 predominant areas are static and dynamic. Static critical path analysis is largely inferior to a dynamic critical path analysis and is usually adopted when the cause is clearly identifiable, there are no complex issues such as acceleration or unproductive work and there is no change in the logic. However, because construction contracts are dynamic, that is the critical path will change, dynamic critical path methodology is the preferred route to retrospective delay analysis. Dynamic critical path methods are classed as time/impact analysis and are based upon the analysis of delaying events at the time they occur. Such methods are recommended by the SCL Delay and Disruption Protocol. However, what method is adopted will be decided upon by factors such as proportionality and what materials are available in order to construct an as-built programme.

Whatever the method…
It was held in Henry Boot Construction (UK) Limited v Malmaison Hotel (Manchester) Limited (1999) 70 Con.L.R. 32, that in order to establish that an event has affected the completion date, it must be shown that it falls on the critical path. In John Barker Construction Ltd v London Portman Hotel Ltd (1996) 83 BLR 31, the conclusion was that a logical and methodical approach is required when assessing contractors entitlement to an Extension of Time so that delays to the completion date caused by the employer can be identified.

Concurrency…
When it comes to assessing entitlement to Extensions of Time in cases of concurrency, the most important point to bear in mind is that it is always ultimately a question of fact as to what is actually causing delay to completion. If a party cannot demonstrate that a relevant event will actually cause delay to completion of the works, there is no entitlement to an Extension of Time. The first step will therefore always be to assess, where there is apparently more than one cause of delay, which event is in fact causing the delay to completion. In the judgment of HHJ Fay QC in Henry Boot Construction v Central Lancashire New Town Development Corporation (1980) 15 B.L.R. 1, he held that if a delay had two or more causes, one of which gave the contractor an entitlement to an extension of time, then an extension of time should be granted.

© Michael Gerard Consulting Limited
January 2005