Preferably, I want to create a completely unsupported opening of 6m, but I've been told that I would need a glued laminated timber beam of 115x495, and that would extend too far downward, so it's not possible. Is there another solution? I will be making a bar counter that's 238cm long at the beginning, so is it possible to place an attractive column in it? The kitchen will be black with a gray countertop.
Yes, if you put a pillar at the end of the bar counter, it will have completely different loads, then you can reduce the dimensions. However, I can't say how much.
There's only 25mm up to the rafters, so I can raise the beam with that, but it would still hang down too much. I looked at the posts in the link and it might actually look nice.
Having it on top of the rafters does sound like a pretty good option! Does it still have the same load-bearing capacity on top as it would if it were underneath? Or does it become a different dimension then?
I have a similar solution in the hallway. We have a round white lacquered steel pole about 70mm in diameter. Mine is completely freestanding, but placing it at the end of the bar counter in a suitable color will probably be quite discreet and out of the way.
It was a previous owner who tore down the wall, so I don't know where it was purchased.
A bar counter with a built-in pillar (so that the countertop goes around the pillar) can look really nice. The pillar itself can be a simple square steel tube, and you can slide on an outer tube in chrome, brass, white-painted, or whatever. Build in a beer tap too.
Not entirely uncommon in older houses with an overhead bearing beam.
We have it in our old Skånelänga.
Same load-bearing capacity as if it's underneath. In our case, the roof beams and the overhead beam are connected with large, coarse forged carriage bolts, type M20-25 approx. But then, of course, our beams are 5" wide. But naturally, there are modern suitable long and coarse screws available for purchase.
As an alternative to a coarse glulam beam on the top/attic, you can build a truss and hang the joist in it.
I know there are threads here on the forum where both methods have been used.