My first post on the forum, I've tried to read up on how to proceed and found some useful information on beam calculation, but no direct explanation of how I should think in my case. I am going to replace a wall on the ground floor of a 1 1/2 story house. (in the 3D images below you can see how I WANT it)
A structural engineer (although not a house constructor) concluded that I should go with an HEA 200 beam... But he calculated assuming the wall also carries forces from the roof.
However, the drawings I have of the house are incomplete, according to my own investigations it doesn't seem like the wall I want to remove supports the roof. (see pictures). For one thing, it feels weak (45x70 studs that FEEL loose). Additionally, there are separate pillars that go from the foundation to the roof ridge.
My spontaneous thought is that the wall "only" prevents the upper floor from sagging.
My question is whether someone knowledgeable on the forum could, based on these images, see if it's obvious one way or the other that I am completely wrong or might be right in this. And how one should think when calculating the beam.
(the house body is an extension and is connected to another house body on the long side)
You need to have a structural engineer calculate it.
As I interpret it, the section with the longest span will be responsible for supporting about 36 sqm of floor joists. Assuming you're correct, the roof is self-supporting. The rule of thumb for residential buildings is that a floor should be designed to support 200kg/sqm plus the weight of the floor joists and structural elements resting on the floor, such as interior walls.
This means your beam may have to support perhaps 3.8 - 4 tons. I have a similar load case in our house (5 x 8m with a steel beam in the middle), the designer chose a HEA180.
For such a significant load, careful calculations are also needed for how the beam should be supported, and possible columns. Often, what's missed when no designer is involved, is what the columns should stand on. In some cases, the foundation must also be reinforced to withstand the point load from the columns. In your case, the middle column will have an extra large load, as it takes up the load from both sides of the beam.
