Contractor requesting calcs 4

[WWTEng]

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.

 

[hokie66]

That attorney may know how the legal system works at times, but his advice is unethical. Not surprising.

 

[TDIengineer]

For those in disagreement, its fine by me. But referring to worth a grain of salt etc.. is just uncalled for.

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.

 

[hokie66]

Would be interesting to hear what Ron has to say about destroying calculations. He probably has more experience with the US legal system than anyone else here.

 

[dcarr82775]

I don't see why who is paying the bill makes a difference. You engineering opinion shouldn't be changing based on who pays the bill. The structure can handle the equipment or not. I see no conflict of interest working for both the owner and contractor so long as the owner is ok with it.

 

[JAE]

There's no conflict unless a conflict arises.

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.

 

[Lion06]

We get asked questions like this a lot on projects. If I have time in my schedule then I will answer these means and methods questions for the contractor (to be a team player), but I would not provide calculations to a contractor who is not our client for a service which we're not being paid.

 

[dcarr82775]

I did forget about the calculation part. I probably wouldn't give them the actual calcs for the purposes of their equipment loading. I would provide framing information to a 3rd party engineer, but probably not my capacity calculations as a basis for their work.

 

[TheoreticalHope]

Another consideration: Technical calculations are a specialized tool of the trade. Things that we assume are clear are easily misinterpreted by even skillful contractors.

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.

 

[steellion]

Shredding calculations is a really bad idea. It’s even bad legal advice. A typical insurance policy will cover errors and omissions claims but will not cover negligence. “Negligence” is defined as not performing up to the standard that would be expected of a typical engineer under similar circumstances. An engineer’s calculations not being 100% correct: that does not constitute negligence. No one is going to pour over every page of your calculations and say “Haha! You forgot to factor in this 1.1 coefficient. Negligence!” What is more likely to happen in the event of a lawsuit is that a 3rd party structural engineer will be brought in to analyze and “reverse-engineer” the structure shown on the design documents. Someone coming in after the fact may be able to analyze the structure with calculations, but they won’t know your design as well as you. If you are a competent engineer, there was probably a good reason for designing something the way you did, and the calculations can prove this. If you don’t have the calculations, you are at the mercy of the expert witness.

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.