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· Västragötalanslän
· 342 posts
I have a load-bearing wall that I am going to take down and replace with a laminated beam. But I'm confused about how thin the wall is. It's a 1 1/2 story house from 75, the wall consists of 70x70 studs and single gypsum on each side. On the 3.4 meters that need to be removed, there are only 5 such studs (previously 6 before someone widened a door).
It doesn't seem very strong, feels like I'm really going overboard when I'm putting up a 115x315 beam.
Am I over-dimensioning or is it just that the existing wall is stronger than it looks?
It doesn't seem very strong, feels like I'm really going overboard when I'm putting up a 115x315 beam.
Am I over-dimensioning or is it just that the existing wall is stronger than it looks?
Is the wall really load-bearing then? Is it 70x70 posts or regular 70x45 studs? What does it support?
I would say that 70x45 is very weak for being load-bearing, especially without reinforcing sheet material (I don't count the plaster as such). However, it's not impossible.
I would say that 70x45 is very weak for being load-bearing, especially without reinforcing sheet material (I don't count the plaster as such). However, it's not impossible.
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· Västragötalanslän
· 342 posts
This is the heart wall on the ground floor, running through the middle along the entire house. 70x70 posts have been used. I know that neighbors in similar houses who have taken down the wall have glued beams instead, so it is definitely load-bearing. I have used a calculation program to determine the size. But it feels very coarse.
Slightly off the main question:
70 x 70 is sufficient for a load-bearing heart wall.
If we consider it as compressed, it holds 17% more than 45 x 95 (cross-sectional area).
If we consider it as buckled, without stiffeners, it holds 2.8 times the load of 45 x 95 (moment of inertia in the weakest direction).
It is only when stiffened with, for example, panels that 45 x 95 becomes superior, roughly tolerating 1.5 times as much.
70 x 70 is sufficient for a load-bearing heart wall.
If we consider it as compressed, it holds 17% more than 45 x 95 (cross-sectional area).
If we consider it as buckled, without stiffeners, it holds 2.8 times the load of 45 x 95 (moment of inertia in the weakest direction).
It is only when stiffened with, for example, panels that 45 x 95 becomes superior, roughly tolerating 1.5 times as much.
Member
· Västragötalanslän
· 342 posts
Okay, stronger than it first sounds in other words then. Maybe I'm not off track after all.
Perhaps measure the beam at one of the neighbors, so you know it will be correct as well.
Perhaps measure the beam at one of the neighbors, so you know it will be correct as well.
Yes, if the neighbors have already done this, what kind of beams do they have?
Member
· Västragötalanslän
· 342 posts
Don't know, I just know that most have the beams built-in and hidden inside the arches. But I will try to find someone with a visible one that I can measure.tommib said:
Or ask about their constructor calculations, which should exist for interventions in the load-bearing structure (requirement for building notification or building permit).
Member
· Västragötalanslän
· 342 posts
Finally found a neighbor who has a slightly over 2dm longer opening and they have 90x315.
I've just torn off the drywall and noticed how carelessly it was built before. On the load-bearing wall, there are only 6 small masonite pieces measuring 4x4cm against the ceiling. The rest of the piece is gapped.
So it will be a 90x315 beam then, as it should apparently be more than enough.
Thanks for the great help.
I've just torn off the drywall and noticed how carelessly it was built before. On the load-bearing wall, there are only 6 small masonite pieces measuring 4x4cm against the ceiling. The rest of the piece is gapped.
So it will be a 90x315 beam then, as it should apparently be more than enough.
Thanks for the great help.