Hello,
I am having trouble figuring out how to dimension the floor joist in the extension of my house. The extension is just under 6 by 6 meters without the possibility of any load-bearing interior wall underneath or a visible underlying carrying beam. The floor joists in the existing house are 220mm, which makes it suitable to use that here as well.
I am considering dividing the area into two parts using some sort of beam solution (something like a hidden carrying beam across the floor joists) either an I or HEA beam with a maximum height of 220mm, preferably lower, or an LVL beam. Then hang a "normal" 220x45mm floor joist on the beam. Do you think that’s a reasonable solution as I believe the floor will become too wobbly by only using 6-meter 220x45mm floor joists with 600 or tighter centers.
/Björn
I am having trouble figuring out how to dimension the floor joist in the extension of my house. The extension is just under 6 by 6 meters without the possibility of any load-bearing interior wall underneath or a visible underlying carrying beam. The floor joists in the existing house are 220mm, which makes it suitable to use that here as well.
I am considering dividing the area into two parts using some sort of beam solution (something like a hidden carrying beam across the floor joists) either an I or HEA beam with a maximum height of 220mm, preferably lower, or an LVL beam. Then hang a "normal" 220x45mm floor joist on the beam. Do you think that’s a reasonable solution as I believe the floor will become too wobbly by only using 6-meter 220x45mm floor joists with 600 or tighter centers.
/Björn
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There are two principal solutions. 1) Some form of load-bearing beam (glulam or steel) and crossing joists of structural timber. Possible dimensions are 90x450 glulam for the load-bearing beam and 45x220 C 24 c/c 600 mm structural timber for crossing joists. 2) Glulam beams 90x270 c/c 600 mm.
The dimensions can be adjusted slightly. Regular structural timber cannot be used for spans around 6 meters.
The dimensions can be adjusted slightly. Regular structural timber cannot be used for spans around 6 meters.
HEA 220 or IPE 270. If you choose two main beams, they can have dimensions of 90x405 in glulam (HEA 200 or IPE 240), and the floor joists can be made with 45x145 C 24. The question is, what is most important? If it's about keeping the construction height down, my second proposal in post #2 is undoubtedly the most efficient. Keep in mind that steel must be fireproofed in some way, and it is significantly more expensive than both construction timber and glulam. A 6 m long IPE 270 costs about 5500 SEK. Glulam is the most flexible material because there is an option to vary the width to reduce the height.