In the last image, the spacing are fine for 1st floor, in fact. I'm just curious about the vertical wood supports, 1 per floor joist, or can be less?
Added to that, another idea to see if anyone has a take on it. Rather than using steel, is there a simple way to make some sort of high strength truss A? It could be 60cm deep...no problem. B is the 76x175 joists at 400mm spacings.
B could be several 75 x 225's bolted together to make a depth of 600mm. Just thinking out loud & understand need to work out the weights.
Added to that, another idea to see if anyone has a take on it. Rather than using steel, is there a simple way to make some sort of high strength truss A? It could be 60cm deep...no problem. B is the 76x175 joists at 400mm spacings.
B could be several 75 x 225's bolted together to make a depth of 600mm. Just thinking out loud & understand need to work out the weights.