Forensic structural engineering is the investigation of failure or non-performance in the built environment

Forensic engineering is a distinct speciality within the wider field of structural engineering, where the forensic engineer focuses on actual physical evidence found at the scene, verifiable facts, and well-proven scientific principles to establish the cause of the failure.  This expertise is quite different from that of conventional engineering design, which instead focuses on taking a client's requirements and constraints and generating an engineering solution based on well established engineering assumptions.  

In construction defect disputes, forensic expertise and design expertise fulfil two very distinct roles. An engineer with design expertise can opine on whether or not a structure was designed and constructed correctly in the first place, whereas an engineer with forensic expertise can accurately determine the cause of a defect or failure in a forensically sound manner. Design is concerned with what should have happened, while forensics is concerned with what actually happened.

Design is concerned with what should have happened, while forensics is concerned with what actually happened.