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Are Structural Calculations required? 8

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wil7

Materials
Mar 12, 2020
2
Hi All,
We have a construction project under review by the township engineer(civil). The township engineer is reviewing a large retaining wall, and demanding calculations for said wall. Our structural engineer is not supplying the calculations. Is this a grey area? Thank you,
 
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Are the plans signed and sealed by a licensed engineer? The calculations should not be technically required in most states. Check with your state's engineering laws.



 
Yes, the plans are signed and sealed by the licensed engineer. I will check on the laws. Thank you.
 
For Pennsylvania, here's a snippet of the "use of seal" rules:
Note that calculations are not listed.
However, some local jurisdictions feel it important to "see" calculations. This, to me, is absurd. Calculations are not an engineering work product but rather an engineering tool to help create the sealable engineering work product. Our construction/engineering culture has lost this distinction unfortunately.

PA_Rules_fssvwg.jpg
 
It does vary some from state to state, but the authority having jurisdiction (your township, in this case), generally has the final say in whether or not something can be built. If the town engineer sees something he doesn't like about the design, he's usually within his rights to require evidence of compliance with building codes if it's not immediately obvious.
 
The city/township engineer will request design calculation only he/she sees something un-ordinary. Under this circumstance, it is better to understand his/her concerns, and set a time to meet and resolve the issues. During the meeting, the design document, including calculations, references and backup materials should be brought in for review/discussion to facilitate the plan review/approval process.
 
Obviously, not my wheelhouse. Nevertheless, we have what's called "basis of compliance," wherein we document through analysis how each requirement is met and with what margin.

I would think the same would need to exist in any structure; you perform analysis to verify that your design complies with the code and with the design's inherent requirements to not fall down or break.

When the reviewer sees something that he feels isn't compliant, how can your PE stand there and say, "it's compliant, but I won't show you how or why it's compliant"? It seems ludicrous that your engineer won't show how he's compliant.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Sometimes there's a difference between verifying compliance for the sake of producing a drawing or spec to be used in construction, and producing a formal calculation suitable for review by the AHJ. So it may just be a matter of payment. If he excluded formal calculations in his quote for engineering services, then he's not going to do them unless he gets paid extra for them. As JAE said, they usually aren't explicitly required by law - so there's nothing technically wrong with not assuming they need to be provided.
 
In California, almost all cities want to see calculations too. So much so, that I'm surprised / shocked that an engineer would refuse to send them. To me that's part of the project.... Making sure the city has the engineering information they need to approve the project.
 
I've only encountered that with federal work, where the government has their own engineers to review the various specialties. With private/municipal work, the plan reviewers around here usually have little to no structural knowledge. They give a standard set of comments, sometimes with some question about why engineered design doesn't match the prescriptive picture in the code, or the occasional misapplied technical "gotcha" they learned in a recent webinar. If calculations were requested, I could probably send in a page of calculus homework and get an approval stamp.
 
But, still, would any engineer really do his calculations on some napkins and hope to dodge the bullet if something bad happens? I mean, what would this engineer do if something collapsed and all of a sudden, every calculation of his needed to be under scrutiny? Would he demand payment to "prettify" his calculations?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
IRstuff said:
I mean, what would this engineer do if something collapsed and all of a sudden, every calculation of his needed to be under scrutiny? Would he demand payment to "prettify" his calculations?
Who is going to want to review only a particular engineers calculations for all of his projects, especially in a jurisdiction that doesn't/isn't qualified to review calculations in the first place?
 
It's a numbers game, no pun intended (for a change). How many structural engineers get sued on a monthly basis in a given jurisdiction? It's probably more than I'm aware of, but I doubt it's enough for most to really worry about it. If you do get sued, then no - you're not going to demand payment - you have to defend yourself. Better yet, your insurance company will hire another engineer to run calculations on the design. But if that's going to happen 1 out of every 500 projects, and the alternative is to include the cost of creating formal calculations even for the 499 cases where nobody will look at them and only get half of the work, then where's the incentive?

I'm not saying I agree with it, but for a lot of small firms and independent engineers it's a business/risk management decision as much as anything else.
 
I believe the IBC gives the local jurisdiction the right to ask for calcs.

I have acted as EOR in ten different States over 25 years and have been asked for calculations exactly once.
 
I don't know somewhere else, but talking about structural engineering capacity of the city of Chicago, New York, both are local level, but we submit the cal when requested.
 
Also note, some municipality do not have technically capable engineers, but something in doubt, they may engage third party reviewer, or require your project to have peer review before considering approval. By holding the "law", I assume there is such law, you are alienating the AHJ, at the risk of delaying your project, if the AHJ does have valid points to refuse issue a permit. Is there a law says the AHJ MUST issue permit regardless of ....?
 
Here is an excerpt from the Florida Building Code Chapter 1, I expect your local Building Code has something similar. In my opinion, this allows the Building reviewer the latitude to request calculations.

107.3.5 Minimum plan review criteria for buildings.
The examination of the documents by the building official shall include the following minimum criteria and documents: a floor plan; site plan; foundation plan; floor/roof framing plan or truss layout; all fenestration penetrations; flashing; and rough opening dimensions; and all exterior elevations:

Commercial Buildings:
1.Site requirements:

Parking
.
.
.

8.Structural requirements shall include:

Soil conditions/analysis
.
.
Structural calculations (if required)


In Miami-Dade and Broward County calculations are required and often times reviewed by the Building Department. As you start going further North or West the building department review is primarily based upon a checklist of items which can often times be as little as "is every sheet signed and sealed"

I prefer the system where local building departments require more through review and especially support the requirements for Structural Peer Reviews of significant buildings.
 
JLNJ,
I don't think the IBC has anything about submitting calculations in Chapter 1 or other chapters. Correct me if I'm wrong - where is it located?

My view of it is that local jurisdictions began asking for calculations thinking they were doing something worthwhile...which isn't true.
My calculations are my tools, methods and aids in helping me, as a design professional in responsible charge, to create construction documents - defined in the IBC and that definition doesn't include calculations.

Now for a state DOT asking for bridge calculations, where the client is an engineering entity, then perhaps the calculation submittal makes sense. But for city building inspectors it doesn't make sense.

 
Interesting seeing what's on the other side of the pond. Over here all structure requires the calculations to be available for review by others, if we ever turned round and said no you can't see them all hell would break lose. That's not to say we have to produce calcs for things we don't need to, if it's skipable the phrase "ok by inspection" is very handy but I can't imagine just using that phrase on single page of paper and having people just accept what I do.
 
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