enough snow, especially if compacted, especially if it involves melting + refreezing cycles turning part of it too ice and even robust concrete building can have some surprising issues
but it's true that for what most places in the world need a slightly tilted and structural stable roof is good enough, if you know how to clean it if things to south
A-frames are often used in snowy climates as a vacation home, park ranger patrol station, or https://en.wikipedia.org/wiki/Wilderness_hut. Such buildings are un-lived-in for much of the year, if not "indefinitely until needed." The building needs to survive, not being crushed by snow, without any human supervision.
As TFA emphasizes, grid electricity is unstable in rural places in winter; which means that even if such a building were able to be grid-connected (often not), and even if the building's owner was willing to spend electricity heating the building year-round in their absence (almost certainly not), the building would be likely to lose electricity at the worst possible moment: when there's tons of snow piling up and no humans there to shovel it.
Tradition says that this is not true but honestly I have no real experience except I have done the calculation for our roof. According to our local building standards at 60⁰ you basically have zero snow load, I am not sure what angle a shallow angle roof is but 30⁰ is max load. 6kN/m² is a lot of extra strength.
In Finland, where you can easily get 30cm or more snow, all roofs are required to stand 100-300kg/m2 by law and most roofs are less than 30 degrees (e.g. 1:2 ratio).
A-frame or even 45degree angle roofs are very rare.
30cm is just kinda cute. Try 600cm - you'll find a lot of A-frames up the mountain, where they routinely get >700cm of snow each year and generally no thaw until spring. Alaska, similarly, but there you'll find more domes and steep-roofed chalets, since it gets proper cold (-40) and insulation uber alles is the rule.
The other benefit of an A-frame is that the snow drifts deeply enough that winter-only cabins don't need as much insulation, because there's a 4m drift on all sides except the front.
Those kinds of places are also where you find "doors to nowhere" on the 2nd floor, because that's the winter access. One door at ground level for summer, one door ~1.5-2m up for winter.
The only limit to how strong you can make a roof is really money. If you space joists or trusses half as far apart you will about double the max snow load.
With 60⁰ there is no snow accumulation at all but 35⁰-45⁰ pith roof will not hold all snow either. After it will accumulate some amount of snow (depending on the weather and an exact pith but rarely more than 50cm) snow will start to slide down.
only to a limit
enough snow, especially if compacted, especially if it involves melting + refreezing cycles turning part of it too ice and even robust concrete building can have some surprising issues
but it's true that for what most places in the world need a slightly tilted and structural stable roof is good enough, if you know how to clean it if things to south
If you get that much snow you should build heating into the roof to melt the snow just enough to slide off
A-frames are often used in snowy climates as a vacation home, park ranger patrol station, or https://en.wikipedia.org/wiki/Wilderness_hut. Such buildings are un-lived-in for much of the year, if not "indefinitely until needed." The building needs to survive, not being crushed by snow, without any human supervision.
As TFA emphasizes, grid electricity is unstable in rural places in winter; which means that even if such a building were able to be grid-connected (often not), and even if the building's owner was willing to spend electricity heating the building year-round in their absence (almost certainly not), the building would be likely to lose electricity at the worst possible moment: when there's tons of snow piling up and no humans there to shovel it.
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Tradition says that this is not true but honestly I have no real experience except I have done the calculation for our roof. According to our local building standards at 60⁰ you basically have zero snow load, I am not sure what angle a shallow angle roof is but 30⁰ is max load. 6kN/m² is a lot of extra strength.
In Finland, where you can easily get 30cm or more snow, all roofs are required to stand 100-300kg/m2 by law and most roofs are less than 30 degrees (e.g. 1:2 ratio).
A-frame or even 45degree angle roofs are very rare.
30cm is just kinda cute. Try 600cm - you'll find a lot of A-frames up the mountain, where they routinely get >700cm of snow each year and generally no thaw until spring. Alaska, similarly, but there you'll find more domes and steep-roofed chalets, since it gets proper cold (-40) and insulation uber alles is the rule.
The other benefit of an A-frame is that the snow drifts deeply enough that winter-only cabins don't need as much insulation, because there's a 4m drift on all sides except the front.
Those kinds of places are also where you find "doors to nowhere" on the 2nd floor, because that's the winter access. One door at ground level for summer, one door ~1.5-2m up for winter.
I love visiting, but I'll never live there!
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The only limit to how strong you can make a roof is really money. If you space joists or trusses half as far apart you will about double the max snow load.
At a certain point the problem stops being the roof, and starts being subsidence of the ground under the increasingly-heavy building.
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With 60⁰ there is no snow accumulation at all but 35⁰-45⁰ pith roof will not hold all snow either. After it will accumulate some amount of snow (depending on the weather and an exact pith but rarely more than 50cm) snow will start to slide down.
Why not "just" make a weaker roof steeper?