Shop Drawing Review: What does the Contract Say?

Editor's Note: This is the first installment in a two-part series on shop drawings. The second part will appear next month (CSE, 01/03). 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, the architect's consulting engineers are its agents.


Reviewing a contractor's shop drawings is one of my favorite parts of being a consulting engineer. Shop drawings often provide more information than manufacturers publish in their catalogs. Sometimes, they even explain how equipment works and identify installation considerations. But most important is that shop drawings tell engineers how well they communicated design intent to contractors.

Keep in mind, however, that unresponsive shop drawings do not always mean the engineer did a lousy job conveying design intent. Contractors can be intractable. Sometimes a general contractor—and even the owner—see the plans and specifications as just a guide.

But contractors should consider shop drawings as a primary way to demonstrate their understanding of the contract requirements—before lines on paper become systems in a building. In fact, AIA A201, Section 3.12.4 explicitly states that the purpose of shop drawing submittals is "to demonstrate ... the way by which the Contractor proposes to conform to the information given and the design concept expressed in the Contract Documents." Shop drawings also help engineers determine whether the contractor understands the requirements of the plans and specifications.

One sees here the basic difference between how engineers look at shop drawings and the way contractors often view them. Engineers review shop drawings to increase the likelihood that defects or deficiencies in the contractor's submittals can be identified before offending equipment or systems are installed.

But the only thing that contractors really want to know is that it is OK to proceed as indicated on the submittal. For this reason, engineers must be careful about how they word their approvals.

Weasel words

By approving a submittal using "reviewed," "checked" or "returning without objection," an engineer is effectively saying that what has been submitted is "as acceptable to the engineer for the project's desired end result as if the engineer had included that particular item in the plans and specifications." (see John R. Clark, "Focus on Shop Drawings," Engineers' Joint Contract Documents Committee No. 1910-9-C, 1985, p. 6.)

However, approving shop drawings does not guarantee the systems will work, or that equipment will be free from defect or properly installed. Take a product substitution, for example. Approval simply means the submitted product is as good as the product the engineer used as the basis of design for the purposes of implementing the design intent.

"Approved as noted," "approved as corrected" and similar language are invitations to disagreement, even when only minor changes are required. Engineers who mark changes on a submittal and return it "approved as noted" never know whether the contractor and equipment supplier agree to make the requested changes. In fact, if the contractor releases the order for manufacture before receiving shop drawing approval, there's a good chance that the change will not be made. Contractors incur little additional trouble and expense to prepare corrected submittals, which become part of the permanent project documentation.

Similarly, to simply "reject" a shop drawing is also unhelpful. If a contractor misunderstands some key aspect of the contract, rejection of the submittal does not solve the problem. "Revise and resubmit" accompanied by notes that explain the required changes is far more likely to produce a compliant resubmittal. A simple rejection might not communicate the need to make changes and try again.

Approved for what?

When an engineer approves a shop drawing, the question is not whether it is approved, reviewed or processed. The real question is: Approved for what?

The answer lies in another question: What does the contract say? Shop drawing review was never intended to make the engineer a guarantor that the contractor would perform in accordance with the contract requirements. AIA A201 Section 4.2.7 says shop drawing review is "only for the limited purpose of checking for conformance with information given and the design concept expressed in the Contract Documents."

Those words say more about what shop drawing review is not than what it is. The section also says a lot about "design concept" without really explaining it. And so, clients—and courts—can be understandably confused about the design professional's role in shop drawing review.

A good guideline is that design concept means elements important to achieve the performance or end results that the specifications intend. This implies a duty to craft the specifications to focus on the essential equipment and system functions and not on unnecessary detail. It also implies that engineers who write specifications and review shop drawings understand the specified requirements and can discern how the submitted equipment meets or does not meet those requirements.

One engineer learned this lesson the hard way. A specification for a steel stairway called for 10-ga. steel landing pads with angle supports, but the contractor's shop drawing listed 14-ga. steel instead. The architect stamped the submittal "Furnish as Submitted." The stairway collapsed, injuring two workers. The architect was sued and argued that its approval did not extend to every detail of the submittal. But the court found the designers liable. [ Jaeger v. Henningson, Durham & Richardson, Inc. , 714 F.2d 773 (8th Cir. 1983)]

Since the Jaeger ruling, AIA A201 has been revised twice. Section 4.2.7 now contains language that submittal review is not conducted for the purpose of determining the accuracy and completeness of other details such as dimensions and quantities, or for substantiating instructions for installation or performance of equipment or systems—all of which remain the responsibility of the contractor as required by the contract documents.

The revised language might have been an attempt to avoid the liability imposed in the Jaeger case. On the other hand, engineers ought to take shop drawing review seriously and recognize that one important purpose of shop drawings is to check for errors that affect performance of the submitted item.

For engineers—and their lawyers—who are concerned about the precise language used, "complies" might be a better choice than "approved." The engineer's review determines whether the shop drawing complies with the requirements stated in the contract documents.

Clear contract language that defines the contractor's responsibilities to prepare shop drawings and circumscribes the engineer's responsibility for review helps everyone understand who is responsible for what. As always, behavior can expand responsibilities and alter the allocation of risks in a contract. For that reason, engineers need to know what the contract says and conform their behavior to it.

Substitutions: design-build?

But what about substitutions? Plans and specifications show one way to carry out the design, but specifications often allow the contractor to supply "equal" equipment by another named manufacturer. In reality, no two products are exactly equal. There are always some variations among products. Manufacturers use those variations to distinguish their products from those of competitors.

When a contractor selects a product other than the one that was the basis of design, does it introduce an element of design-build into the project? Some engineers say it does. The design responsibility associated with using different equipment can vary greatly. For example, a contractor's redesign of a fitting to accommodate a different size air-handling unit is trivial. However, the design responsibility is quite significant when the different dimensions of an AHU require rearranging piping or relocating fans to make everything fit.

In public work, engineers might not be able to hold contractors responsible for coordinating equipment other than that which is used as the basis of design.

For example, in one case the specifications for a fire station called for a particular system or approved equal. The contractor submitted a substitution. When the submittal was rejected, the contractor asked the architect to identify two additional manufacturers whose products he would accept. The architect refused, saying it was the contractor's problem if he did not want to use the specified product. The contractor eventually furnished the specified product, sued for the extra cost and won. ( E. Amanti & Sons, Inc. v. R.C. Griffin, Inc. , 53 Mass. App. Ct. 245, 2001.)

The public bidding statute required specifications to contain the names of at least three eligible suppliers. The problem for engineers is the court's remark that the awarding authority must "demonstrate that there are at least three sources from which a bidder could obtain essential items for the project." The court also said the bidder is not responsible to identify "three sources for materials subject to a competitive bid," and that "providing the name of a single vendor and placing the burden on the bidder to discover alternatives did not constitute competitive specifications."

The case did not discuss who would be responsible if differences among three named products required design modifications. However, the decision seems to imply that contractors should not have to take any initiative to make a specified product work with the rest of the design.

The Amanti case applies to conventional specifications. It does not discuss performance specifications, where different rules might apply.

Section 3.1.2 of AIA A201 requires the contractor to perform the work in accordance with the contract documents. If the specifications name more than one product as suitable for a particular application, those products, even if they are not the ones shown on the drawings as the basis of the design, are not substitutions. Substitutions are products not named in the specifications. Substitutions may be appropriate if the specified product is not available. On a plans-and-specification job, substitutions generally are not appropriate if their only reason is a lower cost to the contractor. Engineers and contractors both should be aware of section 3.4.2 of AIA A201. Section 3.4.2 allows the contractor to make substitutions only with the consent of the owner, after evaluation by the architect.

In next month's Professional Practices, the author will discuss procedural questions, such as which shop drawings to review and who should conduct the review.

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