Stronger Specs for Desired Effects
Experience-mostly bad experience-has led engineering firms to devise ways to tighten their specifications. For clients, the result is usually better performing buildings with better life-cycle cost implications.Downstream of the design phase, substitutions and changes are associated with their undesirable effects, say engineers, which is the main reason that specs have strengthened over the years.
By Consulting Specifying Engineer Staff
Experience-mostly bad experience-has led engineering firms to devise ways to tighten their specifications. For clients, the result is usually better performing buildings with better life-cycle cost implications.
Downstream of the design phase, substitutions and changes are associated with their undesirable effects, say engineers, which is the main reason that specs have strengthened over the years. Mechanical and electrical system designers also point to some other reasons that they are writing more stringent specifications, including:
Energy availability, cost.
Local and state building codes and laws.
Life-cycle cost savings.
Liability implications.
But the top issue is building performance, and firms are writing more closed or restricted specifications to avoid what some 58 percent of respondents to the National Engineering Survey strongly believe is the route to better building-system design.
When a substitution is approved, it is usually because the engineer is backed into a corner: "Availability," says survey respondents, is far and away the most likely reason that changes are ever allowed.