A Guide to Shop Drawings: Who Should Review?

Editor's Note: This is the second installment in a two-part series on reviewing and approving shop drawings. References to AIA Form A201, General Conditions of the Contract for Construction, are to the 1997 edition unless otherwise noted. For purposes of processing shop drawings, when a consulting engineer is the architect's agent, references in A201 to the architect apply to the consultin...


Many firms assign low-level staff to process shop drawings. But the practice—even if perceived as a menial duty—deprives a firm of a useful opportunity to make desired changes before the work is done. Consider this: hire an outside consultant to review the drawings and note suggested changes.

Before dismissing the notion as too costly, consider the benefits. Sure, any changes this independent consultant might make could result in an extra cost to the contractor, but they'll certainly be nowhere near the cost of a problem that is not discovered until after the work is completed. Moreover, if the change is something that would have been included in the bid documents had the engineer thought of it in time, the bids would have been correspondingly higher to reflect the additional work.

Again, before rolling your eyes, keep in mind that the change order cost does not necessarily have to be passed on to the owner, nor should the client expect reimbursement for any claimed design error—professional liability defense lawyers sometimes call this concept the principle of "betterment."

Back to the subject of the independent reviewer. Depending on the job and the circumstances, an outside engineer can sometimes be more objective about whether a contractor's submittals comply with plans and specifications. Such a scenario might also provide a kind of internal peer review. For example, if the reviewing engineer finds a problem, or if the two differ, they can discuss it privately and professionally.

Of course, being able to tell clients about design problems without losing their confidence is a skill that few have mastered. The key seems to be in providing solutions, not just identifying problems. A proposed contract change issued during shop drawing review, accompanied by an explanation, is bound to be less painful than blaming one another when the system does not work as intended.

Review only what's noted

In examining the whole process, there are many steps that can be enacted to save headaches. First, specifications should call for only those shop drawings the engineer believes are needed. If a contractor submits a non-required shop drawing, and the engineer reviews it anyway, he or she will likely be held responsible for having approved it.

Don't simply return these shop drawings marked "not reviewed." It leaves open the question of why it was not reviewed, and in the contractor's lawyer's eyes, it means there was some need to have the engineer evaluate the drawing—otherwise, it would not have been submitted. Instead, return the drawing with a memo stating that the submittal is not required by the contract and has not been reviewed, and the engineer offers no comment on it. By taking precise action and clearly stating the basis for it, engineers can avoid confusion over whether they did review or should have reviewed the shop drawing. Remember that the engineer writes the specifications and the general conditions of the contract that define the engineer's obligations and scope of services—the contractor does not define the engineer's duties.

Do not do the contractor's job

A second headache reliever involves insisting that contractors do their jobs. Under sections 3.12.6 and 3.12.7 of AIA A201 , the contractor must review and approve shop drawings before sending them to the architect or engineer. Engineers should not accept submittals directly from a subcontractor or vendor. This bypasses the general contractor's opportunity to review drawings for coordination. If a submittal contains obvious errors, the engineer should return it immediately with an explanation and a requirement to resubmit once the contractor has corrected any errors. Likewise, if it looks like a contractor rubber stamped a submittal without reviewing it carefully, the engineer should return it with instructions to resubmit after the contractor has completed its review. Keeping a record of the errors or discrepancies in the initial submittal might facilitate review of the resubmittal.

Section 3.12.8 of AIA A201 requires the contractor to advise the architect specifically, in writing at the time of submittal, of any ways that submitted products deviate from the contract requirements. The contractor's approval stamp is the contractor's representation that he or she fulfilled this responsibility. By insisting on the contractor's approval stamp, engineers gain some insulation against claims that they implicitly waived a contract requirement by accepting non-conforming materials or equipment. Engineers can still get into trouble by approving shop drawings with deviations that the contractor identified, but at least it will not be due to unknowing approval.

These precautions may impact the schedule, but remember it is not the only thing that is important. A job that finishes on time but does not meet the contract requirements breeds unhappiness. The contractor is in charge of schedule, and engineers must not let shop drawing review interfere with the contractor's schedule. Section 3.10.2 of AIA A201 calls for the contractor to prepare a schedule of submittals that allows the design team reasonable time for review. If the contractor is going to hold the designer to the review schedule, the designer should insist that the contractor prepare a schedule in advance.

Further, the designer should insist that the contractor express the schedule in terms of milestones, not specific dates. For example, the engineer might agree to process all shop drawings within 10 business days of receipt. An engineer who agrees to process shop drawings by March 15 is asking for trouble, because the contractor might not make the submittal until March 14 or even March 16. The schedule should also address or provide the possibility that resubmittals will be required. Integrating shop drawing review—with adequate time allowed for review—into the construction schedule at the beginning of the job and adhering to schedule commitments can help engineers defend delay claims.

Revoking shop drawing approval

Shop drawings cannot change a contract. In other words, the engineer cannot use the review to impose new requirements. But it also means the contractor cannot use shop drawings to escape a contract's requirements. That is not to say the strategy has never been tried. For example, the specifications for steam piping at a certain university called for welded or threaded pipe. Nevertheless, the contractor submitted—and the engineer approved—grooved piping. Later, the engineer ordered the contractor to stop work and replace the grooved pipe with welded pipe. The contractor sued the owner and the engineer to recover the cost of the extra work. The contractor was not allowed to rely on the engineer's initial approval of a non-conforming submittal to change the contract requirements and leave the grooved piping in place. However, the court allowed the contractor to proceed with his action against the engineer for damages [ Detweiler Bros., Inc. v. John Graham & Co. , 412 F. Supp. 416 (E.D. Wash. 1976)].

In another case, a contract called for a fire-alarm system to be wired with solid copper No. 12 wire. The engineer approved the contractor's submittal "as noted" with a long list of required corrective actions. None of the comments addressed wire size, in part because the submittal did not say anything about wire size.

During construction, a consultant hired for construction observation reported that the fire-alarm system wire was stranded No. 14. The contractor had to replace it. The contractor then filed a claim for a change order.

The contractor argued that neither it nor its supplier thought the No. 14 wire was a "substitution" or "deviation." For that reason, the contractor claimed it could not be faulted for failing to call the wire size to the engineer's attention during the submittal process. The court disagreed with the contractor, noting that, "Anyone working in the electrical field ought to know that stranded conductor is not solid, and that 14 AWG wire has a smaller diameter than 12 AWG."

The submittal approval could not alter the contract requirement. The approval was effectively revoked, and the contractor had to replace the work at its own cost [ Twigg Corporation v. General Services Administration , GSBCA 14387, cross-motions for summary relief denied: June 4, 1998, GSB CA 14386, 14387 denied; GSBCA 14899 granted in part: February 11, 2000].

Design delegation

In the market today, there a number of specific shop drawing related issues engineers need to be aware of. The first involves the controversy over design delegation vs. abdication.

For years, specialized systems have been specified on a performance basis. The architect specifies criteria, and the vendor provides the detailed design. In HVAC, for example, the design engineer specifies a sequence of operation for temperature controls and the specialty contractor selects the hardware to implement the specified sequence.

Contractors sometimes claim the drawings for these systems contain too little information as to how to build something, forcing them to design the system themselves. Designers claim they are appropriately delegating details of design , like steel connections, to specially qualified professionals like steel fabricators.

In such cases, the contractors' argument is not so far-fetched. Shop drawings are not a substitute for design documents and designers should not expect contractors to design the project or figure out how to make the building or the system work. Section 3.12.10 of AIA A201 attempts to define the division of design responsibility between the architect—responsible for the design of the project—and the contractor, who the contract might require to design a portion of the work, but who is usually limited to a sub-system or ancillary work.

When the contract delegates a portion of the design to the contractor, the architect must specify all performance and design criteria that the contractor's detailed design must satisfy. The architect is not responsible for checking that the contractor carried out the design properly, but the contractor is not responsible for the adequacy of the specified performance or design criteria. Design-build projects present more extensive design responsibilities on the part of the contractor that need to be specified in that contract.

Temporary vs. permanent

Even people in the construction industry sometimes lose sight of the distinction between temporary and permanent work. The former falls within the contractor's exclusive realm. Shop drawings are permanent work to describe systems as they will be configured.

As a general rule, engineers should not review submittals concerning the proposed implementation of means, methods, techniques, sequences or procedures of construction. Engineers also generally should not review shop drawings for temporary work. Reviewing them could subject the engineer to have accepted responsibility not normally undertaken by a design professional. There are exceptions: An engineer might want a contractor to submit a procedure for making a cut-over from old to new systems on critical operations. The engineer also might want a contractor to submit a written phasing plan that shows how the contractor plans to maintain continuity of service. In these examples, the purpose of the engineer's review is only to see whether the contractor has developed a reasonable plan, not evaluate details or provide an opinion on whether the plan is appropriate. To avoid interfering with the contractor's sole and exclusive right of control over means, methods, techniques, sequences or procedures of construction, the engineer's review or comment letter should state the scope and purpose of the review—that the engineer's review is intended to confirm that the contractor has developed a plan—and not to make an independent evaluation of the suitability of the plan.

One final thought on shop drawings: Engineers should not underestimate their value as a way to learn about products. Sometimes, contractors select products simply on price. Sometimes, it's based on incentives like expense-paid sales conferences at desirable vacation spots. But just as often, contractors select products based on reliability—no callbacks, technical support and service after the sale. Engineers rarely have the opportunity to experience first-hand how products perform over time. Contractors who service the equipment have that opportunity daily.

A reliable contractor's choice of a particular product is one of the strongest recommendations a product can obtain. Engineers should make shop drawing review part of delivering a functional project, not a bureaucratic obstacle.

Real power: Use it wisely

Shop drawings really are a thing of beauty. How so? The engineer writes the contract—in the form of the specifications—and is then allowed to administer, enforce and interpret it. Perhaps the first answer to any question about managing shop drawings should be another question: "What does the contract say?"

Maybe engineers should challenge every section in their specifications by asking, "Why do I need this?" or "What do I really want here?" Enforcing the contract specifications will be a lot easier under challenge if every requirement has a sound reason.

But consistency is important. Engineers should be careful that their actions do not contradict either the words or intent of the contract. Engineers should check that their contract for professional services and their sections of the specifications are consistent with each other and with the other professional services agreements as well as the contract for construction.

Finally, with specific regard to shop drawings, samples and other submittals, specify and review only those that are necessary—and have a reason why they are needed.

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