Hello,
I am going to build a mezzanine floor where I want to avoid wooden beams because I lose too much ceiling height with the heavy beams required.
I have no experience working with steel beams and would need help figuring out what type and dimensions I need. The sketch below shows the layout of the room and the placement of the mezzanine. I quickly moved the parts from the sketch where I started with just wood, so dimensions and placements are approximate.
The room is 6m wide and the floor shall be 3.3 meters deep. There should be an insulated partition wall at the front of the floor. The space will be used as an office.
Ideally, I want steel beams with inserted wooden joists, so the floor is no thicker than the height of the steel beams. The beams need to rest on columns so that the construction is independent of the house structure.
I need the type and dimension of 3 beams of 6 meters and 6 bearing columns of 2 meters.
Or suggestions for other solutions.
The beams need to rest on pillars so that the structure is independent of the house frame.
Are you sure the floor structure allows this? With what you propose, the entire weight will rest on 6 points on the floor. This is only possible with a reinforced concrete floor.
It is a concrete floor and I intend to weld plates for the posts so that they distribute the weight and can be attached to the floor, and the walls at the top.
If it is possible to attach to the walls, maybe the posts are not needed? And one more thing. With these stairs, maybe you have too little height between them and the ceiling. The hole in the ceiling should be "L" shaped. I would also consider placing the stairs in front so that they do not take up space on the first floor.
Common wall studs are unfortunately not sufficient to support the weight. I would need to go into the wall and reinforce it, which I would prefer to avoid.
Absolutely, among other things, it's due to the design of the stairs that I feel the need to change the material in the floor joists to get better space. The stairs are a placeholder and will be designed after I get help with the floor calculations. The sketch above is approximate, but thanks for the good and important details. I have the stairs under the floor to save space in front 😎
But what I need help with is determining the dimension of the steel beams (3 or more?) I need for a floor measuring 6*3.3 meters that will support an office and an insulated inner wall.
Ordinary wall studs are not enough to bear the weight unfortunately.
Regardless of whether the wall structure is steel or wood, the posts in the walls should withstand such a load. Even 95x45 wood has a very high resistance to vertical load. Consider that the wall sheathing additionally strengthens these beams. And I think you should assign this project to someone with knowledge.
I feel that you are focusing on the wrong thing. I'm not interested in changing the general design of the structure I'm building. I'm well aware of the compressive strength of (different) wood, but I would still not support a second story, bolted to the sides of six 1"3 posts no matter the sheathing. Your proposal would require more work on the structure of the existing building than what I'm prepared to do, in order for it to work. I'm not saying it isn't possible, just that I can't suspend the floor from the six studs that would meet the support beams. I'd have to rest the floor "on top" of the studs, which would require opening up the wall. I'd prefer to have a relatively free standing structure.
The only thing I'm unsure about is the dimensions of the lateral steel beams. That's why I'm assigning that bit to someone with knowledge.
I have now made new drawings with correct dimensions.
The beams are HEA 120 and the columns are HEA 100 (just as a starting point). Is this sufficient to support the floor and the 90 mm thick wall without deflecting unacceptably?
The columns will have 8 mm steel plate pads and an angle to rest the beams on, as well as to stabilize the columns by attaching them to the wall. The red parts are welded to each other.
The wooden floor structure is 120x45mm, notched to fit inserted into the steel beams.
