Contractor requesting calcs
Contractor requesting calcs
(OP)
We worked on renovations to an existing auditorium and our work included structural calcs to determine the capacity of the existing floor for some added loading. The contractor needs to bring in a tall/heavy cherry-picker to renovate some art work on the ceiling of this building. He has requested our calcs. I assume he wants to get an idea of the floor capacity.
Personally I wouldn’t mind giving him the calcs because a) he could make the same request to the owner and the request would trickle down to us anyways b) I think it would help the contractor expedite his work.
So I think we should be OK giving him the calcs with a clear disclaimer that his question relates to mean and methods and any conclusions his structural engineer draws from these calcs are at their own risk.
Have you ever received a request like this and if so, how did you handle it?
Thanks.
Personally I wouldn’t mind giving him the calcs because a) he could make the same request to the owner and the request would trickle down to us anyways b) I think it would help the contractor expedite his work.
So I think we should be OK giving him the calcs with a clear disclaimer that his question relates to mean and methods and any conclusions his structural engineer draws from these calcs are at their own risk.
Have you ever received a request like this and if so, how did you handle it?
Thanks.






RE: Contractor requesting calcs
RE: Contractor requesting calcs
But if the contractor wants to exceed the design loads, they need to hire their own engineer and evaluate the design. I'd say the more distance you place between that decision and your company, the better.
RE: Contractor requesting calcs
This is done all the time and it is not wrong for you to recommend/assume that any special construction related loads be dealt with by another "construction" engineer as these sometimes can be
highly specialized - i.e. related to the equipment loads.
As EOR of the project, it might even be proper for you to insist on another SE to review it.
RE: Contractor requesting calcs
Dik
RE: Contractor requesting calcs
They should insist that the check of the structure should be the contractor's (and their SE's) responsibility.
RE: Contractor requesting calcs
RE: Contractor requesting calcs
It can create a condition where there is a real or percieved conflict of interest.
RE: Contractor requesting calcs
I agree with Dcarr. At the moment, there isn’t anyone who knows that structure better than you do, given the work you have already done, and there is no one better than you to do this additional study and engineering. And, that’s what you should be selling, rather than giving away your previous work which was done for a somewhat different, but not unrelated reason. Obviously, you shouldn’t do this for no compensation, with no additional investigation and study if needed, and you shouldn’t have more liability foisted on you without the appropriate involvement and input. But, you can be sure you will get dragged into the fight if something does go wrong, so you might just as well have some control over it, and put your existing knowledge to good use. This should also be less costly to the contractor and take less time too. It is a funny thing the way we do business these days, by slicing and dicing this kind of work, so no one knows what the other is doing, everyone has to fart around redoing what others have done already, responsibility and detail gets lost in the shuffle, etc. Of course, the attorneys love the additional deep pockets and the confusion, that just add to complex and very expensive resolution of any problems.
RE: Contractor requesting calcs
That way there's no conflict.
RE: Contractor requesting calcs
I don't even like providing them to the owner, review the contract and what is required. This may sound not very customer friendly, but with the amount of attorney's in the United States I would error on the safe side.
Have a verbal discussion with the contractor, explain to him your understood design loads and capacity, but I would document or send anything in writing unless contracted to do so.
RE: Contractor requesting calcs
RE: Contractor requesting calcs
RE: Contractor requesting calcs
RE: Contractor requesting calcs
As to destroying calculations like TDIengineer suggested some firms do, I think that is negligent.
RE: Contractor requesting calcs
Drawings are approved not the calculations so destroying the calculations is not negligent in my opinion. The design can always be justified again by calc if necessary. If you get into a lawsuit, the calculations just become ammunition for the forensic attorney's engineer, this has been my experience. Why else would a large firm destroy their calcs? Pure liability reasons... If you think it's negligent, blame the countless attorneys. Just my opinion!
RE: Contractor requesting calcs
BTW, in a professional liability action, you are sure to lose if you can't document your design with calcs, which should be stamped and signed. The other party's attorney is going to have a field day.
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"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill
RE: Contractor requesting calcs
This is the first I have heard of systematic destroying of calculations. Throwing them away or losing them after years have passed, yes, but destroying them willfully once a permit is issued, stupid.
RE: Contractor requesting calcs
RE: Contractor requesting calcs
RE: Contractor requesting calcs
RE: Contractor requesting calcs
I find your lack of respect for lawyers and the law naive. It's all about controlling information, think NSA. Attorney's don't play fair, they try and make money. Unlike engineer's lawyers are good at that part.
If only engineers existed in this world, keep all your calcs.. Frame them in fact. But in this country that is litigation happy you don't even have to have done anything wrong necessarily to get dragged into a law suit. And if a large firm has a junior engineer prepare some calcs that aren't properly checked and you combine that with contractor error, you could be in for trouble.
The contractor will do his best to drag the engineer's and architects down with them. Using the calculations to justify as such is a usual path is what I have read and seen.
But again, we are all entitled to our own opinion. That's the beautiful thing about this country!
Regards.
RE: Contractor requesting calcs
RE: Contractor requesting calcs
RE: Contractor requesting calcs
Taking fees for engineering services from two different entities (who might someday get in a lawsuit/conflict) on the same project could put you between two squabbling firms.
I would agree that if the owner/client agrees with you providing those services for a fee then perhaps its just an accounting/bookkeeping issue as to where the money flows.
But there's always an issue of the sense of client trust that gets warped when you split "alliances".
We just try to avoid it as much as possible.
RE: Contractor requesting calcs
RE: Contractor requesting calcs
RE: Contractor requesting calcs
I would try to avoid this conversation:
Contractor: "You have a 100 psf load permitted for this 200 sqft slab. Therefore, I can put my 20000 lb outrigger load in the middle of the slab without problems."
Engineer: "Let me take 5 hours to explain why this is a bad idea and why you don't understand my calculations."
I don't mind providing calcs for reviewers to verify my assumptions, I don't like giving calcs to contractors so that they can derive their own engineering conclusions from.
And as for destroying calcs: that seems foolish. They are a valuable resource long after shit has hit the fan. Rather than systematically destroying evidence, take that time to ensure your calculations are accurate and your assumptions are valid. Preemptively shredding your design aids is like placing bad reinforcing steel then 'accidently' pouring concrete so the engineer can't find your mistakes. Foolish.
RE: Contractor requesting calcs
As far as getting rid of them as soon as the permit is issued, before the building is even constructed, well that’s just bad practice. I constantly refer back to my calculations during construction when RFI’s start coming in. What do you do when the contractor asks if they can change something for a field-fix or an alternate detail or the architect needs to cut a hole you weren’t anticipating, re-calculate everything in that detail over again? It’s good to know what you were thinking during design, because by the time it gets built, you may not remember.