When we prepare a proposal, it must be based on something specific. For example, we prepared a proposal for a three-story college building project. The wall type schedule specifically called out 31⁄2-inch 20-gauge metal studs 16 inches o.c., for walls extending to 17 feet, 6 inches. However, the engineer required deflection criteria of L/240.
The Steel Stud Manufacturers Association's "Limiting Heights" manual indicates that a 31⁄2-inch 20 gauge metal stud spaced at 16-inch o.c. could not be used to reach 17 feet, 6 inches. In order to use a 31⁄2-inch stud at 16 inches o.c., it would have to be 18 gauge rather than 20 gauge due to the L/240 requirement.
If the deflection criteria were L/120, a 20-gauge stud could have been used. What bothers me is the fact that the wall type schedule specifically called for 20-gauge studs; however, the deflection criteria required 18 gauge.
We also recently bid a seven-story metal stud load-bearing project with similar contradicting issues. The architectural plans specifically called out 31⁄2-inch 25-gauge metal studs at 24 inches o.c., for interior non-load bearing walls. The structural drawings contradicted the architectural drawings, indicating that all interior non-load bearing walls shall be 31⁄2-inch 20-gauge studs at 16 inches o.c.
Contradictions between the architectural and structural drawings are interesting because these contradictions can benefit, as well as hurt, a subcontractor. In the above examples, it appears the structural engineer and architect did not review each other's work to make sure the documents were complementary to one another.
Contradictions between the architect and engineer are becoming more commonplace. In most cases, it has become the subcontractor's responsibility to either have the issue clarified or take responsibility.
If you choose to have the issue clarified during the bid process, you may find that both the engineer and architect may simply tell you to propose the most stringent interpretation or say there is not enough time to issue an addendum correcting the issue. If there is time to issue an addendum, you cannot be sure what the addendum will say until you get it.
If an addendum is issued, you have no way of knowing if your competitors have received it, read it or made an adjustment for it. Addendums are simply additional documents that modify the original construction documents.