I'm going to replace a rotten roof (the battens, that is) which was previously just sheet metal directly on the battens, with one with underlay. Previously, there were approximately 38x145 battens, which have sagged a bit...
The span is about 380 cm, snow zone = Stockholm. I'm going to lay 22 mm tongue and groove boards and then underlay on the roof.
Can 45x220, K24 on 120 cm centers suffice, or do I need to go down to 60 cm centers?
The span is about 380 cm, snow zone = Stockholm. I'm going to lay 22 mm tongue and groove boards and then underlay on the roof.
Can 45x220, K24 on 120 cm centers suffice, or do I need to go down to 60 cm centers?
It probably works fine with cc1200.
600 seems excessively close.
Edit: I got curious and checked what the forestry industry's handbook had to say about flat roofs.
They state that a C24 45x220 handles 3.54m
(safety class 2, climate class 2, deflection L/200)
So, a bit shorter, but also with higher requirements than what one would demand for a garage.
And the old ones worked (almost).
600 seems excessively close.
Edit: I got curious and checked what the forestry industry's handbook had to say about flat roofs.
They state that a C24 45x220 handles 3.54m
(safety class 2, climate class 2, deflection L/200)
So, a bit shorter, but also with higher requirements than what one would demand for a garage.
And the old ones worked (almost).
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And their calculation is for a flat roof. Since we have a slope here, it becomes a bit different. The vertical cross-section becomes larger, but unfortunately, I don't have the knowledge of how to calculate that.