Use of SE stamp

[PostFrameSE]

I have been asked to stamp an agri-business structure with my SE stamp for loads less than the ASCE 7 prescribes. This structure is actually going in an area of the US that does NOT require buildings to follow any code or design standard. So for argument sake, is it wrong, or dangerous to use an SE stamp to give a building owner the confidence that a structural engineer has designed the building for a windspeed of 75mph when all engineers know good and well that the ASCE 7-05 has minimum windspeeds of 90mph? This is what the owner has asked for because he doesn't want to pay for what it would take to design it to a 90-mph wind speed.

Put another way, is it my "right" as a design professional to use my stamp to "certify" whatever I want so long as I state the criteria by which I'm stamping it, or does the mere fact that I obtained the stamp bind me to follow generally accepted documents like ASCE 7 regardless of whether there is an AHJ stating that there is a code or standard to follow?

Thanks

 

[JStephen]

From a disciplinary action: "Therefore, it was determined that Mr. X's actions were misleading and contrary to generally accepted engineering standards, and that he failed to perform these engineering assignments in a careful and diligent manner". The "generally accepted" part is the issue there.

From a practical standpoint, I find that nobody reads a disclaimer or note anyway, and if you stamp a drawing saying it's good for 10 mph wind speed, the interpretation is that "It's good!".

 

[PostFrameSE]

Thanks JStephen for your quick response.

Anybody with a contrary opinion or is this how the majority of engineers feel out there?

 

[Jerehmy]

what are the chances that people would be inside it during a hurricane? how close in proximity is it to other buildings in case of debris, etc hitting property/someone?

you said agri-business. warehouse? that's how I'd go about it if there are no codes governing.

 

[chrislaope]

My 2 cents:

if it is in a 90mph wind zone, you have to follow 90mph wind speed to do design/checking/sealing. However because it is an agri-business structure, you can use I = 0.87 in the design/checking/sealing, which in the final result will be equivalent to a 83.9mph wind with a occupancy category II building.

 

[PostFrameSE]

This is Midwest.......so no hurricanes. Tornados perhaps. It is clearly in a 90mph wind speed area.

Chrislaope............at least the way I understand the ASCE 7, it doesn't matter if I can use an I = .87 because the 10psf wind pressure on the vertical surface ALWAYS trumps and I'm stuck with pressures that are 150% - 250% higher than what I get by calculating with the coefficients. I wish I would find out that I'm looking at that incorrectly, but that minimum stuff controls regardless of the I.

Thanks.

 

[Ron]

PostFrameSE....as a licensed engineer, you may exercise your engineering judgment in any application; however, as JStephen alludes, you still have to meet the prevailing standard of care of the area.

The standard of care is, generally, that level of service ordinarily provided by other competent members of our profession, providing similar services in the same locale and under the same or similar circumstances.

Just because it has "always been done that way" for non-critical agricultural buildings does not necessarily establish a standard of care. If you want to proceed, then document and justify your reasons for either deviating from the code or having your design comply with the code.

 

[TehMightyEngineer]

As a newly licensed engineer this is an interesting question that I can't add much too. However, I wonder if you could perform the design as requested, document and clarify that this does NOT meet current codes, and then not stamp it. If there's no code to meet then I assume no stamped designs are required. Thus, the client probably just cares about the quality of the design and not the seal on the prints. Any thoughts on what this would do regarding liability? Would this make it worse or better?

Maine Professional and Structural Engineer.

http://www.fepc.us

 

[dhengr]

PostFrameSE:
Who is the owner trying to please in terms of building permits, codes and the like if there is no local bldg. code or AHJ? In many jurisdictions ag. bldgs. do not have to meet the bldg. code, with certain limitations. But, that doesn’t relieve the owner of the potential liability if someone gets hurt by one of his inferior bldgs. Then ask yourself if he would have any qualms about suing you, if and when something went wrong. He doesn’t want to pay the little extra it would cost to build the building to meet min. code criteria which are generally accepted/prevailing in the wider surrounding area. And, he wants you to bless the inferior building. It sounds to me that he has some concern about the building he had built and paid for, and is now looking for an insurer of last resort. And, with owners who look on proper design, engineering and construction that way, you can bet your bottom dollar they will sue you if anything goes wrong, all for a small fee to you, now. Tell him to talk to his insurance agent, you aren’t in the insurance business. I certainly would not stamp any plans for this building, but I would review the design and drawings, and tell the owner, in a signed report form, with plenty of caveats and disclaimers, where it doesn’t meet the min. code which I normally work to, with warnings of the potential problems and consequences.

 

[JAE]

Well there are state adopted building codes that sometimes cover all the areas not generally covered by local cities.

In one midwestern state it (the state) adopted the IBC 2009 and requires its use for state-owned buildings and:
"in any political subdivision which elects to adopt the state building code".
So you might check the county as they may have adopted the IBC.

But if there is no adopted code, no requirement for a permit, no inspector, etc. it seems that whatever you do will be lawful, but not necessarily in your best interest.

So it really boils down to an ethical issue and a pragmatic risk-control issue for you.

Ethical
1. You are providing what the owner wanted, but perhaps the owner doesn't understand the ramifications of that decision. A 70 mph wind is only 60% as strong as a 90 mph. Does the owner understand that not being an engineer?
2. If you design and build to 70 mph, other people besides the owner (the owner's family, friends, visitors, the general public, or subsequent building owners) will all be exposed to a less-than-code building - a higher risk that they would not otherwise be exposed to. This reflects back on Ron's standard of care issue.
3. You, as a licensed engineer need to FIRST look out for public safety and welfare. If only cows or pigs inhabit the building that is one thing - but my guess is that others (see the list in item 2 above) will be in the building.

Risk
1. If you design to 70 mph, and a storm comes in and damages the building, you probably have a good defense (notes on the plans, documentation of your agreement with the owner for 70). So some level of risk control there.
2. But - the owner can always claim they didn't know the ramifications of the 70 vs. 90 and still sue you.
3. Will your professional liability insurance carrier cover you if you don't design to the standard of care? You might call them and ask.
4. Research specific wind site data from a local weather station to see how the average 3 sec. gust wind speeds and standard deviation compare with the national average. In the midwest it might be a bit higher than the national average.






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[PostFrameSE]

Great responses all! Thanks so much for the collective wisdom!!!!

 

[jgailla]

From the civil side, I always use some kind of code when designing.
These are not life safety issues, but I want to be able to point to a standard if questioned.

 

[jeffandmike]

How did the owner become aware of the differences in the design/construction requirements of a 75 mph building versus a 90 mph building?

As engineers, sometimes we can be our own worst enemies by being "too truthful" and offer explanation where none was requested, where none was necessary, or where it wouldn't have been in our best interest to offer an explanation. This is a tactic attorneys use in depositions related to forensic engineering, for example. Get the engineer talking, saying a lot of words, and inevitably they will spill something that is useful to them, even if the engineer didn't actually do anything wrong.

For example...

(Bad)
"Mr./Ms. Owner, if I engineer this building to meet the building codes, which require a 90 mph wind speed, here's what will need to be done structurally. That being said, there is no local requirement to follow 'any code or design standard'. If I use 75 mph, this is all that will need to be done structurally. You'll have a substantial cost savings with the 75 mph design."

(Good)
"Mr./Ms. Owner, here are the signed/sealed plans you requested." (designed to the 90 mph wind speed)

A couple of questions I have... how was the 75 mph wind speed arrived at? If there not "any code or design standard", and if 75 mph is better than 90 mph (economically speaking), why not use 65 mph (or even less) for your wind speed? Why was ASCE 7-05 selected as the code for a building where there is not "any code or design standard"? Why not select ANSI A58.1-72, for example?

You reported that you "... have been asked to stamp an agri-business structure with [your] SE stamp for loads less than the ASCE 7 prescribes". This wording struck me as a bit unusual. Did you actually personally complete all of the structural calculations/plans yourself, from scratch, or is this something that was brought to you by the owner, and they asked you to review it and to sign/seal it, for example? Not that there is anything necessarily wrong with that... I was just curious of the history of the project. Stated another way, are you the first engineer (or design professional of any sort) that the owner has worked with on this project?

 

[chrislaope]

PostFrameSE (Structural) (OP):

Reading your post, you say:

“…..at least the way I understand the ASCE 7, it doesn't matter if I can use an I = .87 because the 10psf wind pressure on the vertical surface ALWAYS trumps and I'm stuck with pressures that are 150% - 250% higher than what I get by calculating with the coefficients.”

Just curious, is this agri-business structure a round steel tank? If it is a round steel tank, you might pursued in a wrong direction. I mean this agri-business structure might actually meet ASCE7-05 code requirement, but you just under-estimated the actual structure strength. I have several past experiences that my first simplified analysis and calculations always showed the structure is not strong enough, then I did more detailed and accurate analysis and calculations and found the actual structure is far more strong than I first thought. Just some thoughts for your consideration, please ignore it if not relevant.

 

[PostFrameSE]

Excellent question jeffandmike. A little history. No engineer has worked on this project yet. These are not real complicated buildings (rectangular shape, common truss roof profile, etc) that we're dealing with here and so our salesman, who knows a little bit about codes and a little bit about ASCE 7 felt it would be more cost-effective to sell the building with a 75-mph windspeed. He knows what happens when a project is designed to the ASCE 7 and it oftentimes requires a better diaphragm, perhaps some shearwalls, stronger members at times due to C & C loads, etc. All of those things cost a little more money, so I'm pretty sure that it was sold at a lower wind speed to reduce the cost of the structure. Since an SE stamp would not have been required for the project, either the customer thought "OK...............that's fine to use a lower windspeed but I want the assurance that it really can handle those loads so prove it with an SE stamp" OR the salesman offered it to him as a means of shedding any doubts about whether the structure would be designed "adequately" or not.

This is going to sound really loosey-goosey to many of you I'm sure to hear that a salesman can somewhat dictate some of the responsibilities of the engineer. I'm rarely put in a situation like this, but since I find myself here this time we're having this discussion.

 

[jayrod12]

I would think you are more than in your right to seal calculations for a building to a lower than code level wind. It's just structural analysis.

But, I would not be sealing the plans. Provide sealed calculations if the owner wants proof that the structure is capable of withstanding 75MPH winds. Inform the owner that you are unable to seal the drawings because the design wind load is not up to code.

I think that's a reasonable middle ground. You're providing proof it can withstand the client requested loading, but you are not taking liability for the building because it doesn't meet minimum accepted code level values from the surrounding area (even though it is in a non-code governed area).

 

[PostFrameSE]

Mmmmmmmm.........interesting thought jayrod12. That's a different twist that might be workable. Hadn't thought of it in that light before. Thanks.

Have other engineers done that before? That seems to make a lot of sense.

 

[manstrom]

The code does use I factors to reduce for agricultural structures that pose a low risk to human life. If your client doesn't want that, I would put a BIG note on the drawings and follow up with a letter that says basically "I designed this for the loads / conditions that you wanted, it is not code compliant, but it is designed for the loads that you requested. There is a possibility if building failure in an extreme wind or snow event"

CYA.

I can appreciate that the client doesn't want to pay for a cadillac, just a pinto. But don't give him the impression that it is code compliant.

When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.

-R. Buckminster Fuller

 

[JAE]

I don't think that sealing calcs, sealing plans, or writing a letter makes a bit of difference to your exposure to liability.

I would be very reluctant to design below standard code requirements - even if the owner wrote me an indemnification letter.

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[Canuck67]

Expanding on JAE's wise comments, even if the Owner were to write an indemnification letter, what happens a month or year or two from now if the Owner sells their property to a new, unsuspecting person, who should have a reasonable expectation that the building was designed adequately.