Hello,
I recently bought a house where the previous owner, along with a carpenter, built a balcony on the second floor. I recently noticed that it was sagging a lot and therefore measured the joists and center-to-center spacing.
The construction consists of support beams 45x195 screwed into the wall at the back and supported by 3 pillars at the front (I believe the pillars are 2 pieces of 45x90, but they are covered in decking, so I'm not sure).
On the support beams, there are joists at 600 mm center-to-center that have been cut into wedges of 45x145 for water drainage with dimensions of 45x120 at the façade that slopes down to 45x100 above the front support beam and carries rough-hewn boards + asphalt paper, then back with wedges 45x25-45x45 and decking on top.
The wedges (screwed joists) span 2.6 meters. I have not performed complete calculations, but for that span, the joist dimension should be 45x170 according to the timber guide's dimensioning tool, calculated with decking only at 0.3 kN/sq m.
Now I need to stiffen the floor structure, and my question is how best to proceed.
The simplest solution might be to add another support beam between the 2 existing ones and support with pillars, but that results in a lot of pillars so I would prefer to avoid that.
Should I add joists to reduce the center-to-center to 300 mm?
Otherwise, my thought is to brace the floor structure in the middle with 45x120 in the gaps and glue/screw down decking/slats/similar for tension across them, creating an integrated beam to distribute the load over more joists, but I can't find anywhere how to calculate that. Additionally, this mainly mitigates the sagging when walking on the floor structure; the snow load will still be evenly distributed over all the joists.
I recently bought a house where the previous owner, along with a carpenter, built a balcony on the second floor. I recently noticed that it was sagging a lot and therefore measured the joists and center-to-center spacing.
The construction consists of support beams 45x195 screwed into the wall at the back and supported by 3 pillars at the front (I believe the pillars are 2 pieces of 45x90, but they are covered in decking, so I'm not sure).
On the support beams, there are joists at 600 mm center-to-center that have been cut into wedges of 45x145 for water drainage with dimensions of 45x120 at the façade that slopes down to 45x100 above the front support beam and carries rough-hewn boards + asphalt paper, then back with wedges 45x25-45x45 and decking on top.
The wedges (screwed joists) span 2.6 meters. I have not performed complete calculations, but for that span, the joist dimension should be 45x170 according to the timber guide's dimensioning tool, calculated with decking only at 0.3 kN/sq m.
Now I need to stiffen the floor structure, and my question is how best to proceed.
The simplest solution might be to add another support beam between the 2 existing ones and support with pillars, but that results in a lot of pillars so I would prefer to avoid that.
Should I add joists to reduce the center-to-center to 300 mm?
Otherwise, my thought is to brace the floor structure in the middle with 45x120 in the gaps and glue/screw down decking/slats/similar for tension across them, creating an integrated beam to distribute the load over more joists, but I can't find anywhere how to calculate that. Additionally, this mainly mitigates the sagging when walking on the floor structure; the snow load will still be evenly distributed over all the joists.
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Maybe triangular elements are needed between the pillars? I don't really understand what provides lateral stability (left-right in the image viewed).