Shop drawings: who is responsible
The definition
Section titled “The definition”Shop drawings are detailed drawings produced from the detailed design, for the manufacturer, matching the equipment and technology of the factory and containing the further information needed for production. They generally contain no structural calculation and no technical description.
That definition places them precisely in the chain: the design sits in the detailed design, and the shop drawings translate it into what the particular works can make.
What they add to the detailed design
Section titled “What they add to the detailed design”Fit to the manufacturing technology
Section titled “Fit to the manufacturing technology”The same structure is made differently on a different line: a different profile range, different tooling, a different maximum length. The shop drawings take that into account.
Breakdown to piece level
Section titled “Breakdown to piece level”Member schedule, part marking, layout, assembly sequence — everything needed for manufacture and erection.
Manufacturing data
Section titled “Manufacturing data”The basis of the program handed to the machine. In LGS that is the file given to the line controller; in steelwork the cutting and hole setting-out.
Who is responsible for what
Section titled “Who is responsible for what”The most common source of dispute, so keep it clean:
- The structural engineer is responsible for the design of the structure and for the solutions set out in the detailed design.
- The shop-drawing designer is responsible for producing the shop drawings in accordance with the detailed design and to suit the manufacturing technology.
- The manufacturer is responsible for making it to the shop drawings.
If it emerges during shop drawing that the detailed design does not solve something, refer it back to the structural engineer — it is not something to “solve” in the shop drawings.
When they come up
Section titled “When they come up”For every structure not made on site: steelwork, light gauge steel frames, precast concrete, windows and doors, services components. In LGS technology they are fundamental, because manufacture precedes erection.
Why a good detailed design is critical
Section titled “Why a good detailed design is critical”Because shop drawings cannot substitute for missing decisions. If the bracing, the anchorage or a connection has not been decided, the shop-drawing designer either waits or decides — and the latter is a bad arrangement. The content of the detailed design.
The point
Section titled “The point”Shop drawings are a translation: they translate the designed structure into the language of a particular works. What has not been designed cannot be translated.