Delay analysis methods
Produced in partnership with Tim James Seal
Delay analysis methods

The following Construction guidance note Produced in partnership with Tim James Seal provides comprehensive and up to date legal information covering:

  • Delay analysis methods
  • Six common methods of delay analysis
  • Agreeing the methodology
  • Key features of delay analysis
  • Comparing delay analysis methods
  • Which analysis method to chose?

Delay analysis is a technical method employed by programming/planning specialists to identify the delay and the cause(s) of that delay to the completion date of the works on a project. By doing so, contractual culpability and liability for the delay can be established. Computer software is a common feature of delay analysis.

This Practice Note provides a summary of the different methods of delay analysis commonly used, and the key terminology that arises. It follows the approach taken in the second edition of the Society of Construction Law Delay and Disruption Protocol (SCL Protocol), at guidance section 11. For more information on the SCL Protocol, see Practice Note: Delay and disruption in construction projects—The Society of Construction Law Delay and Disruption Protocol.

There is no easy or brief way of explaining each delay analysis method because of their highly technical natures. Only short summaries are provided here and the reader is encouraged to read the SCL Protocol or other detailed and authoritative analyses.

Delay analysis as a whole is a difficult topic and can be challenging for the non-specialist to access and understand.

Six common methods of delay analysis

There are six commonly used delay analysis methods:

  1. impact as-planned analysis

  2. time impact analysis

  3. time slice windows analysis

  4. as-planned v as-built analysis

  5. retrospective longest path analysis

  6. collapsed as-built analysis

These methods are sometimes known by