We are looking at metal roofing for our home. Our roof slope is 3/12. We live in Maine and we get a lot of snow.
With such a low slope is the snow going to come off ok or is it going to take forever to come off?
Why is it important that the snow "come off" of the roof? Do you expect it to overload the roof structure? If so, you should be thinking of increasing the slope or reinforcing the roof.
We just get so much snow here and a lot of people had roofs cave in last winter. That is a good point, but can any roof handle 6 feet of snow on it? Because that's what my yard had at some points last winter.
In snow country you go with a 12/12 roof so you don't get cave-ins. With 6 foot of snow the snow shovels should have been busy for a while. Clearing off the roof.
Tell me about it. That's all we did was shovel last winter. That's why we were hoping for metal to help that some.
In Maine, the state building code requires a roof to be designed to resist a snow load of between 60 psf (on the coast) and 100 psf (in the northwest). These loads can be reduced as the slope of a roof increases above 6 in 12 and should be increased where drifting is likely. On a 3 in 12 slope roof these loads would translate to fresh wet snow depths of between 5 and 9 feet.
You must design the roof for the expected load or buy a snow rake and use it as needed. These loading requirements have a lot of safety factors built in which explains why more roofs don't collapse every winter.
I live in an Oxford brand mobile home. The mobile home was 70 x 14 and we added a 12 x 56 addition on the back. The new part of the roof is 22 feet from the peak to the end. I know they put knee walls in it but structure wise I'm not sure what else was done. A roof rake isn't long enough to do it.
Mobile homes are built to a different standard than houses and I suspect the addition didn't involve professional or town oversight. What allows these structures to survive is the short spans of their roofs so you may not have a problem but I would ask the builder what snow loading he assumed.
If the ceiling starts to sag, I suspect you'll have to get up there and shovel the snow off. I know someone who used a snowblower to do it.