Statics for wall breakthrough, is the floor plan sufficient?

Good day to everyone,

I would like to consult the expertise of you professionals, as I have a question regarding the structural engineering of my house. We want to tear down a wall to create an opening. I have now found an engineering firm that would calculate the structural engineering for me. However, the structural engineer said that the floor plan alone is sufficient to calculate what kind of steel beam is needed. Can that be true? Isn’t it important to do an on-site inspection? Isn’t it necessary to check what material the ceiling is made of and whether there are other walls above the wall that is to be torn down? I find it a bit strange that a simple floor plan, which is 50 years old, should be sufficient. I would appreciate your opinion. Thank you very much,

Wilhelm

However, the structural engineer said that the floor plan is sufficient for him to calculate which steel beam is needed. Can that be true? Isn't it important to do an on-site inspection?

Yeah, if you generously estimate based on the highest loads, then you can probably do it that way.
The question is whether you just want any steel beam, or if it should be as small as possible.

But I would still expect an initial visual inspection to see if the floor plan even fits.

All right, thank you very much. The structural engineer has provided an offer of 400 euros and optionally listed an inspection for 90 euros....I’m naturally wondering whether that makes sense or if I can save the 90 euros.

... an oversized beam would be more expensive ...

I suspect that most structural engineers don’t actually calculate anything anymore but rather look up some tables that contain standard values for standard building materials with standard dimensions, with a lot of tolerance. A friend of mine, who is a (metal) stair builder by trade, also told me that whenever they give a custom-designed staircase to a structural engineer to calculate the minimum thickness of a beam or a column, the dimension that comes back is always one where he says he didn’t actually need a structural engineer to know it would hold. It seems to me that you always have to tell a structural engineer explicitly: "Only as thick as necessary, but as narrow as possible!"

Thank you very much for your feedback... yes, I also heard from a construction contractor that the structural engineers calculate very generously. But as a layperson, you don't know what is necessary and what is not. You have to trust... but of course I don't want such a huge beam.