CROSS - Unauthorised substitution of materials on the rise?

The latest CROSS (Confidential Reporting on Structural Safety) newsletter published by the Standing Committee on Structural Safety (SCOSS) highlights the unauthorised substitution of cold rolled hollow sections for hot rolled hollow sections by buyers. The problem is possibly being exasperated by the current economic conditions.

The structural properties of these two materials are different and this may compromise the original design and leave buildings with structurally inadequate members. Thomas Consulting have also come across an incident of such substitution.

Concern is expressed that buyers of structural materials sometimes seem to be cost driven and do not appreciate the importance of the steel grade and other material properties.
SCOSS reports that it has become aware of other unauthorised changes being made without the knowledge of the designers. The unauthorised use of non-structural steel box sections, changes to structural fixings and gas membranes (see previous newsletter) are more examples of “value engineering” compromising original designs. SCOSS are concerned because it is difficult for the designer to prevent others from effecting such changes other than by making it clear, on drawings, or in accompanying issue slips, that all changes are to be referred to the designer.
Those who undertake “value engineering” need to ensure that their decisions do not affect the original design criteria. Buyers and Quantity Surveyors need to be aware that unauthorised changes to specified materials can have serious consequences.

http://www.scoss.org.uk