Error in the static calculation, supposedly our mistake

Hello everyone,

since we treated ourselves to a house, I have been reading a lot in this forum. Now the point has come where the search function no longer helps me, so I am actively asking the question.

Info upfront, we are completely renovating our house and awarding contracts independently.

We want to remove a wall almost completely and have therefore commissioned a structural engineer with the corresponding calculations for support. We provided detailed plans as well as clearly communicated our requirements. So far, so good. We received the report and accordingly (privately) ordered the steel beam.

When we were on site with our mason, it turned out that the beam is too short.

After careful examination of the report, it turns out that it was calculated with the dimensions of the 1st floor instead of the ground floor. We confronted the structural engineer with this, and according to him, this is normal. This structural calculation is only a rough guideline and with the report, it must be checked on-site which length the beam actually has to have. A deviation of 40cm - 50cm is normal. The executing trade must check this, and it is incomprehensible to him how we, as private individuals, could order the beam. That the measurements match those of the 1st floor is pure coincidence. Furthermore, the calculations also include positions where the self-weight of the beam is taken into account. In my opinion, the entire calculation becomes obsolete if we change the length.
Lastly, his opinion was that we can ask any architect we want; a report is a guideline, and the executing trade must then order the beam accordingly.

For me, this is a calculation error. The structural engineer is stubborn and sticks to his opinion. Before I take further steps, I wanted to first consult the collective knowledge here.

Many thanks and best regards

Basically, it is true that the dimensions of the static calculations are not relevant for the on-site situation, neither in new construction nor in existing buildings. However, this should especially be pointed out in the static calculations for private individuals. If this clause is missing, you could get them in court for it, but the effort is probably not worth it.

Just my opinion on the whole thing.

Yes, a static calculation should be as close to reality as possible, but it does not replace detailed planning and surveying.

What does the steel beam cost? No chance to swap it for another one? Basically, you could have also swung the tape measure.

Well, he got a construction drawing for it specifically and all the information very detailed. He did use them, but with the measurements of the 1st floor instead of the ground floor. So now it is 50cm too short. In my opinion, that is not insignificant. That he as a structural engineer screwed up is clearly only him, but he is just a stubborn ******** and refers to the fact that the executing trade has to check the report again. And we didn’t do that. We assumed everything was correct because as laymen you don’t really understand it anyway.

What really annoys us is not even the fact but how. The beam goes to eBay or at worst to the scrap dealer but we are met with arrogance like we have never experienced from any trade so far. He would have to redo it anyway because it is wrong.

I just want to know, preferably from someone who is familiar with the overall processes, whether the report is ok like that and 50cm tolerances are normal (in this case our fault because we didn’t check the measurements accordingly beforehand) or if it was his fault and he has to create a new report. (and also our fault because we ordered blindly). At least he should make the effort again :P

My opinion is, if a highly paid structural engineer gets an accurate plan and everything that goes with it, I can expect that a matching report will be produced.

Regards

...I’m getting worked up again.

The fastest answer you get is from another structural engineer.

Book that to the account for saved site management.