Design Drawings, Shop Drawings, As-built Drawings

Doing design work for a contractor? Make sure the contractor knows the difference between design and shop drawings. Design drawings, often showing single line ductwork and piping, can seldom be used for construction purposes. Design drawings show how engineering-wise things would work. Contractor needs to make shop drawings to make sure things would fit in the field. Contractors develop scaled shop drawings based on design drawings, final equipment submittals, and field conditions. Whereas the design engineer, in general, makes sure specified equipment and accessories would fit, the engineer cannot possibly produce shop drawings at design stage because the information about equipment to be purchased by the contractor is missing. The third set of drawings made in the life of a project is the set of as-built drawings. The as-built drawings are almost like the design drawings except that they show the actual way the equipment and accessories were installed.