ConstructionPro Week, Volume: Construction Advisor Today - Issue: 27 - 10/29/2009

Contractors' Reasonable Expectations of Drawing Detail

Contract drawings do not depict every detail of every component of a construction project. Some aspects of the work are fleshed out in drawing details. Other details, however, are left unaddressed in the contract. The contractor is required to propose this detailing through the submittal of shop drawings, usually prepared by subcontractors and fabricators.


The problem with this system is twofold. Design responsibility, and a certain degree of risk, is shifted to the contractor. Yet the contractor is not given information needed for accurately pricing its bid, possibly motivating the contractor to carry a contingency in its bid price.


In a recent case, a contractor argued that the absence of a drawing detail justified the contractor’s exclusion of that component from the bid price. The contractor was informed that it could not use the lack of detail to read the requirement out of the contract, even if the omission made it difficult to accurately price the bid.


I’d like input on how much detail can a contractor reasonably expect in the contract drawings? What are the appropriate limits on the use of shop drawing submittals?  Please feel free to comment below.

In next Monday's issue of Construction Claims Advisor:

  • Periodic Subcontract Payments Not Tied to Value of Work
  • Smaller Projects Could Not Be Aggregated to Meet Experience Requirement 
  • Retainage Raises Questions of Balance and Fairness





In accordance California Public Contract Code the plans and specs need to provide enough information for a "competent mechanic" to perform the work.

One should not need to be a design professional to carry out the work. It is the design consultants job to incorporate all code requirements into the working drawings/specifications.

The above answer relates only to Public Works.

A contractor should not exclude an item shown on the drawings, even if it is not detailed. However, the contractor can not be expected to interpret the design intent behind the item not detailed.
For example, if a floorplan shows what can reasonably be interpreted as a countertop, it should be expected of the contractor to include the cost of "a countertop" in his bid price. However, the client should anticipate potentially receiving plastic laminate rather than granite. Likewise, he can expect a credit for a similar value if he elects to omit the supposed countertop from the scope of work. 
While it is the contractor's responsibility to provide what is shown on the drawings, it is not the contractor's responsibility to interpret the drawings.
Same theory can be applied to code interpretations. It is the architect's (and thus the Owner) responsibility to provide drawings which represent accurate code interpretations, not the contractor.
(Note: The above philosophy is not applicable to a design/build contract, however. Design/build provides responsibility on the contractor for the scopes of work which are design/build.)


If the Specifications specifies an Installation Standard that has to be met (ie: ASTM C 745), then it would be expected that these minimum stadards are to be met without detailing to the Nth degree. At the same time, the architect needs to understand what these standards mean and not ask for anything additional outside of the Contract Documents.


Of course this applies to gypsum wall construction and any other type of construction material may change the out come of this discussion.

A thought on the issue:


My partner has been practicing architecture since 1965. He says that the difference between a contractor's bid today and a contractor's bid 40 years ago is that contractor's used to bid the price of the building based on the drawings. Now they bid the drawings - period.

This is not a slight to contractor's, but instead is the nature of the bid market. I have to feel this is one of the reasons that design/build has grown in popularity.

The EOR has a duty to provide sufficient detail or ensure the contract docs. clearly indicate the burden lay on the contractor for a heightened effort. Then we get into patent/latent defect issues & if patent, and having a material influence on how the Contractor would bid, he has a duty to inquire prebid. Ignorance of convenience is just that when $$'s are riding on a detail that does not APPEAAR clear.


Thirty years ago a school could be built with 30 sheets of architectural drawings and 1" of mimeographed specs. Now it takes twice as many sheets and specs by the pound. What changed? The skill level of contractors and the litigation climate has changed dramatically. Contractors are now risk managers rather than professional builders. It imposes a level of responsibility on the design professionals that is grossly disproportionate to their compensation and forces contractors to depend on change orders for their financial success. What a terrible system we have! Maybe IPD will help.


We are now entering a discussion with no specifics. So, we all have to "make up a story". Of course if the drawings show a threaded piping system, then they don't need to call out thread lubricant and teflon tape. Sheetrock, some sort of appropriate attachment. Stucco, some sort of lath. However, I would need more specifics -- what did the Contractor who lost in court leave out??? --- to comment on the specific case.


The bidding climate has been driven by too much competition in the industry. Many unqualified contractors are bidding projects with little to no experience in that particular building type as a means to stay in business. It has forced reputable contractors to try and compete with price by looking for any and every excuse to not include something in the bids. Quality based selection will help eliminate the low-ball contractors from bidding on projects with which they have too little experience. Then, maybe, bidding contractors can ask for clarification during bidding, rather than making an assumption to the lowest possible price for anything that might be somewhat unclear.


I don't know where you are but in Denver we usually have a deadline for questions about a week before the bid is due. That would give the contractor plenty of time to ask about anything that was unclear. If this is really a problem it sounds to me like the contractor needs a better class of clients. If there is really a question of level of finish why not bid per plans and specs and give an alternate for the upgraded finish. That way both sides can discuss options with all of the facts.


Contractors in a competitive bidding climate are looking at drawings up until bid day and may not catch every mistake shown on a set of plans before RFI cut-off date. However the contractor who bids trying to account for mistakes, errors and omissions on drawings will likely not be the contractor who is the low bidder. Our firm bids and builds using structural drawings and use Architectural drawings for clarity. Recently we had an architectural firm tell us that we should have bid the masonry 12 inch block shown on the architectural drawings and not bid using the structural drawings which showed 8 inch masonry walls. Go figure!


I agree with Brad Hanson. As an electrical contracting project manager, if my estimator fail to submit at RFI for something left out on the drawings that is necessary to reasonably price the project, shame on him. Most commercial and industrial projects allow for time to submit questions prior to bid.


As a fire sprinkler contractor, we see the ambiguities of construction documents all of the time, the phrases "coordination issue" and "the sprinkler contractor shall modify his work to accomodate other trades at no additional cost to the owner" are all to common and they show the lack of hands on construction knowledge the people have assembling the documents we work off of, dare I say it is a miracle that any money is made on Plan and Spec projects.


I have worked on both sides, once as a professional design engineer and now as a HVAC/Plumbing contractor. The drawings the contractors are supposed to bid from are a far cry from the quality of drawings produced in 1965. I want as much detail as possible. We have been asked to "develop a ductwork/piping detail" for some fan coil boxes on recent job--which needed to have pipe and ductwork sizes. That's not the contractors job, the engineer should have known how to do a piping detail- AND SIZE THE PIPE. Unfortunately, most engineers haven't been trained properly and/or lack field experince to see what a mechanic needs in the field.


Shop drawings are the check and balance system in the project. IF the contractor goes with a subtitution then it provides the engineering with a chance to reject or accept the submittal. If the contractor submits per plans and specs any liabilty goes back to the design professional.

It's sad but our list of exclusins and exceptions on our contracts are longer than the scope of work, due to poor drawing and specifications.

Regarding pre-bid requests for information or clarification, I agree that this is not only prudent for a contractor, but legally mandated. In my very brief synopsis of the recent case, I did not mention that the contractor had inquired about the lack of detailing. He received misinformation. But unfortunately for the contractor, the purveyor of that information was not the duly authorized government contracting officer.


Bill hit on a key problem:


"It imposes a level of responsibility on the design professionals that is grossly disproportionate to their compensation and forces contractors to depend on change orders for their financial success."

I doubt there is anything new about the core problem of owners wanting more than they are willing to pay for, but the problem does seem more widespread. We offer both design/build and design/bid services. Every time we go over the pros and cons of both, the owners tend to focus on wanting the lowest possible price by bidding the project. Later they seem to forget that we discussed the pros and cons to the bid process. Then they start to expect us to be the construction police. As I write this I realize that we have to improve our process of educating owners.

I agree with Tom, the quality of the drawings are ridiculous. It is not the contractors responsibility to design the work. It should be the responsibility of the design team to over lay the different systems and draw the plans accordingly. Most documents come with disclaimers, not responsible for errors and omissions. Contractors are being held responsible for things the smart guys left out. Additionally we are told our submittals must be very specific they don't want other product data on the page. Yet at least 20% of every set of specs is not applicable to the specifec project. As an electrical contractor we have seen a serious decline in the skill of engineers. It is time some of the burden is removed from the sub contractors. Feel free to email me with your comments.


Back to the original question about how much detail a contractor can expect. Design professionals should provide a full and complete set of drawings and specs that cover the primary details and materials. In particular, things like roof and flashing details should be shown for every situation that is signifcantly different. On the other hand, design professionals should not be in the business of preparing step-by-step instruction manuals on how to build buildings. We appreciate receiving intellegent RFIs that indicate that the contractor is carefully planning out his work and wants to get it right.


As an MEP Coordinator for the Mechanical, Electrical and Plumbing Subtrades, I can certainly attest to the lack of thoroughness in design and engineering with contract bid and issued for construction sets. It is commonplace for us to catch many design errors and "inconstructability" elements of a project. Then it is on our shoulders to rectify and offer solutions to issues that should've occurred in the design development phase; not during construction at the 11th hour. Responses to RFI's only initiate further questions, as the design "team" consistently seems to pursue all trades independently, without regards to each other. I believe wholeheartedly that the Owner should hold the architect and engineer to a higher standard and require them to have more responsibility with the overall project design and construction. "Drawings and specifications are diagrammatic and may not show all elements of construction..... Contractor shall assume all responsibility...." is not acceptable.


In the not-so-distant past, mechanical and electrical drawings for building construction were understood to be diagrammatic in nature, defining the work symbolically and depending on the craftsmanship of experienced trade contractors to install the work. Even now, electrical power floor plans are largely symbolic, showing receptacle locations, panel locations, and circuit numbers, leaving conduit routing up to the skill and ingenuity of the journeyman electrician.


Similarly, duct and piping layouts were largely single-line except in mechanical equipment rooms, where large-scale drawings and sections more closely described the work to be performed.

Particularly in public work, where proprietary specifications are generally frowned upon, the design engineer is forced to rely on generic details and manufacturer's installation instructions even for large equipment. The "or equal" or "comparable product" items might vary widely in size, connection details, etc. from the "basis of design." But the design engineer is not compensated sufficiently to issue three different details to cover three acceptable manufacturers.

It has come to the point that here in NC the state regulatory agencies are requiring the design engineer to reproduce on the drawings the UL firestopping and fire damper installation details, rather than relying on language to require competent contractors to properly install such items.

We have to remember that buildings are not products, and cannot be designed to the detail that a manufacturer designs an automobile or a desk. In the manufacturing world, product design is refined through scale models and full-scale working prototypes before products are released for general sale. As designers, we have always, and must continue to rely on skilled, experienced trade contractors who can translate diagrammatic design drawings into installations that work as designed.

To follow up on my earlier comment, we have seen review comments from state agencies to require architectural detailing to show sloping the floor to a floor drain.


Is that degree of detail necessary to get a building built? If so, our building construction industry is in big trouble!

This question all comes down to responsibility. If each party to the process would take responsibility for their work most of the problems would go away. We recently had a job where a particular electrical panel was indicated by a schedule only. The panel was not on the riser diagram, not on the plans,and did not have a breaker to feed it in any other panel. Unfortunately, this was a large project with many panels and we did not catch this mistake during bidding. When the problem did come to light we turned in an RFI to ask how the panel was to be fed. The engineer's answer to the RFI was: "The intent of the drawings is clear. The licensed electrical contractor should feed the panel as required." He was afraid we would request a changeorder. This was a design issue that the engineer should take responsibility for. If it results in additional work, then a change order is warranted.


Why is it that 100% Design Development/Issued for Construction documents for a building will have multiple systems, including structure and building elements that, when put together, cannot co-exist? I've seen so many times where the structural engineer develops his/her structural design; the architect has building elements that he/she wants (i.e. ceiling heights, door frames/transoms, etc; and mechanical contractor has their design criteria based on air flow and comfort level/AIQ, etc. Bottom of steel ends up at 10'-0". with specified 9'-0" RCP ceilings, recessed lights and 12" deep insulated ductwork, vent lines and roof drains all trying to co-exist in the same space... Then it's the CONTRACTOR's responsibility to figure out how to make it all work (as if they screwed up). Heaven forbid anyone blame the design team. Meanwhile, the Owner and ultimate end-user ends up with design concessions and a product that is compromised. Hats off to the GC's and subcontractors, as they make things work; and seem to carry the "designers", who would otherwise be in a bad place without them. **Note: I realize this is not the case in all projects, but it seems to happen more than not.


There is no doubt that design professionals make mistakes, and that much too often drawings are not coordinated between trades.


There is also no doubt that craftsmanship in the field is a dying art.

I spent 10 years as a construction inspector/administrator in a design firm. There are many times I walked a job site with a project manager/superintendent, pointed out some installation, and asked "Is that the best you can do?"

Submittals/shop drawings (submitting and reviewing) are the most important part of any project. Contractors are responsible for submitting coordinated, project specific submittals and design professionals are responsible for reviewing them. This is the final step/check to make sure all parties are on the same page. Unfortunately there have become too many "rubber stamps" out there. As an electrical engineer, I include wiring diagrams for every motor load on a project as part of the design. Too often I see typical wiring diagrams submitted that were originally drafted in the 1970s. (Since I was not designing projects when I was in elementary school, those diagrams are obviously not project specific.) I take submittal review seriously and rarely return one without comments. I know other design professionals that think it is the contractor's responsibility to coordinate everything and just return submittals with CYA comments. Both sides need to do a better job (by just doing their respective jobs).


The problem with design drawings lacking information is not getting better. I have owned an engineering firm and a construction management company and it is my experience that what is being presented as design drawings today is a far cry from what they should be. I also agree that the quality of supervision provided by the contractors today is far less than it was 20 to 30 years ago. Both groups need to better train their people to provide a better product.






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