Are Shop Drawings Really Needed?
The drawings and specifications prepared by architects and engineers show the general design concept of the project and each of the major components and their relationships to each other. Some of the subcontractors and suppliers must prepare additional drawings, diagrams, schedules, and other data to illustrate the specific way in which their particular company or shop will undertake to furnish, fabricate, assemble, or install their products.
Shop drawings are needed by the fabrication shops for their own use in instructing their own personnel how to carry out the requirements of the contract documents. Fabricators will produce the shop drawings even if they are not asked to submit them for architect’s approval. In many cases, the building could have been built satisfactorily even if the architect had not reviewed the shop drawings.
The principal reason architects and engineers need to review the shop drawings is to ascertain that the contractor understands the architectural and engineering design concepts and to correct any misapprehensions before they are carried out in the shop or field. They review shop drawings of any particular trade or component to determine if the contract drawings and specifications have been properly understood and interpreted by the producers and suppliers.
The shop drawings should prove to the architect’s satisfaction that the work of the contract would be fulfilled. If the shop drawings indicate that the work depicted will not comply with the intent of the contract drawings and specifications, the architect has an opportunity to notify the contractor before the costs of fabrication, purchase, or installation have been incurred.
The costly and wasteful alternative to this procedure would be simply to wait until the work is in place and then examine it and condemn or reject it. It is much more economical to review and correct the shop drawings than to remove and replace erroneous construction. Proper use of the shop drawing review system should prevent costly errors caused by misunderstanding of the contract requirements.