Replace load-bearing wall with HEB120

[rentz]

Hi!
The wife wants a bigger kitchen and to replace the wall between the hall and the kitchen (which is load-bearing for the middle floor, see attached documents) with a beam. In the living room, there is an HEB120 in the floor structure that supports. The question is simply whether I can place a similar HEB 120 in the intended location?
The beam will therefore lie under the floor structure, but will it handle the load within reasonable limits for deflection? It is a bit wider on that side, so the load won't be distributed equally over the beam, but will it make a huge difference?

If you need more information, give a shout!

 

[mdab]

Hello
Assuming the same loads across the entire floor, you need a 28.8% stronger beam where the span is 3.7m compared to where the span is 3.4m.
However, since we don't know how much safety margin the designer had when he chose HEB120, that doesn't help much.
But if you choose HEB 140, you don't need to calculate it, then you know you have at least the same strength as in the rest of the floor.
If you choose HEB120, you'll have to wait for someone here to calculate it from scratch for you.

 

[mdab]

PS. HEB140 is approximately 74% stronger than HEB 120

 

[anaitis]

Now, it was probably the deflection that was of interest.
Then it is the stiffness that determines.

 

[mdab]

Yes yes. I called it strength instead of stiffness, I think most people understood what I meant. The floor's capacity against deflection is perhaps what I should have said to avoid misunderstandings...

 

[rentz]

Thank you for the response!
What could be the reason for the closer spacing of the beams on that side?
The floor above looks essentially the same...

The increased number does indeed increase the static load on the beam. So perhaps it can compensate somewhat for the increased span.

 

[mdab]

Don't have a good answer for why it's denser in the upper area of the drawing... Bathroom on the floor above?

It's just as you say. Wider spacing between the beams indicates less load and compensates for the higher span. You could imagine that it's a maximum of 33% higher load in the denser area. c-c40 compared to c-c60 is 33% "stiffer" and the increased span required a beam that is 28% stiffer. So you should manage with HEB120 after all.
BUT I would still recommend HEB140 as I wrote in the first post just to be safe. The cost will be a couple of hundred extra?

 

[rentz]

Now that I take a closer look at this, I see that the stairwell means the beams there don't rest on the "outer wall" (the partition wall in the semi-detached house). That must mean for the part of the beam located at the well, it takes additional load, so maybe a HEB140 isn't sufficient either?

 

[haavard]

If you are going to do it right, you should make a notification to the municipality about changing the load-bearing structure. If the municipality does its job, they will require you to provide a calculation.
For your own safety, I think you should prepare the calculation regardless of whether you involve the municipality or not.

 

[rentz]

If you want to do it right, you should file a report to the municipality about changing the load-bearing structure. If the municipality does its job, they will require you to submit a calculation. For your own safety, I think you should prepare the calculation whether or not you involve the municipality.

That's true, maybe someone here can help calculate this? It would be greatly appreciated.