ᐅ Structural calculations for wall openings: is the floor plan enough?

Hello everyone,

I would like to ask for your professional expertise regarding a structural question about my house. We want to remove a wall to create an opening. I have found an engineering firm that would calculate the structural requirements for me. However, the structural engineer said that the floor plan alone is sufficient to determine what kind of steel beam is needed. Is that possible? Isn’t it important to conduct an on-site inspection? Shouldn’t it be necessary to check the ceiling material and whether there are other walls above the one to be removed? I find it a bit strange that a simple floor plan, which is 50 years old, would be enough. I would appreciate your opinions. Thank you very much,

Wilhelm2022

Wilhelm2022 schrieb:

However, the structural engineer said that the floor plan alone is enough to calculate which steel beam is needed. Is that possible? Isn't it important to do an on-site inspection?

Well, if you estimate generously based on the highest loads, you can probably do it that way.
The question is whether any steel beam will do or if it needs to be as small as possible.

But I would still expect at least an initial visual check to see if the floor plan even works.

All right, thank you very much. The structural engineer has provided a quote of 400 euros and optionally listed a site visit for 90 euros... I’m wondering if that makes sense or if I can save the 90 euros.

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

I suspect that most structural engineers no longer perform detailed calculations but instead refer to various tables containing standard values for standard building materials with standard dimensions, allowing for a significant margin of tolerance.

A friend of mine, who is a (metal) staircase manufacturer, told me that whenever they submit a custom-designed staircase to a structural engineer to calculate the minimum thickness of a beam or a column, the measurement they get back is always one where he says he didn’t really need a structural engineer to know that it would hold.

It seems to me that you always have to explicitly tell a structural engineer: "Only as thick as necessary, but as narrow as possible!"

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