That depends on the construction. The relatively flat metal type won't carry near as much as a gable roof. Standards vary by region, and it is important to know which region the home in question was built for. Since they are mobile homes, it is possible that it was moved from one region to another.
Only the paranoid survive.
I carry a gun because a cop is too heavy.
"Since I'm in charge, obviously, we screwed up." -Barck Obama
I don't know but we got 30 or more inches from a snowstorm yesterday and an elderly womans' mobile home roof collapsed in Martinsburg, (WV) The report said it was an older one and I don't know how old or what shape it was in.
Our local mountains got 4-5 feet of snow at the resort level, about 7,000 feet elevation. In the week following the storm, the roofs of 6 mobile homes collapsed under the weight of the snow. Here is an article about the roof collapses, with pictures of the snowload.
Something to keep in mind is that a foot of light fluffy powdery snow weighs a lot less than a foot of heavy wet sloppy snow. Not all snow is the same. Our snow was light fluffy powdery snow. If it had been wetter, there would have been far more roof collapses.
Mobile homes, like any other building, are designed for the loads that are expected in the area that they are expected to be used. If it is an older mobile home, unless the specifications are on a label somewhere, your guess is as good as anyones. Usually they are designed to minimal standards, and often use minimal materials, too. I would err on the side of caution.
I noticed the old flat roof mobile on my neighbors property (nobody has lived there for several years) has collapsed a bit with the ice and half foot snow we got.
My opinion unless you live in a desert, flat roofs arent the greatest idea. You save a few bucks on construction, then deal with leaks and snow loads and such for a lot of years afterward.
If I had a flat roof mobile, I would build pole frame around it to support a conventional roof over it. Course if you live in an area without bunch rural building permit crapola, you just as well build a small pole building and live in it, forget the particleboard headaches. Mobile homes are basically just the modern socially acceptable version of the old tar paper shack. Socially acceptable cause some company/bank is making "easy monthly payment" scam money off poor people from them. Somebody puts up their own shack and nobody makes money off it. I've lived in them for brief periods and I'd as soon live in some old out building that at least is made of real solid wood. Particleboard is one of the stupidest ideas ever.
"What would you do with a brain if you had one?" -Dorothy
"Well, then ignore what I have to say and go with what works for you." -Eliot Coleman
Sorry about sounding so abrubt. Mobile homes are a bit of a sore point with me. The ratings don't mean as much as they should with the older ones. Again, sorry .
Is there anyone living in the one you own? If so, will they clean it off? Probably expect the world be given to them if they do.....
i'm not sure in MN but in Michigan they have to be constructed for snow belt areas..in zone 5 here in michigan and zone 4..they require a much stronger construction than south of here..we are required to have 2x6 walls and at least a 4/12 or 5/12 peak on the roof..flat roofs are not allowed on mfgd homes in our area..those codes are fairly new though so older ones might not survive a huge snow load.
Having been around MH all my life, I'd like to offer this advice- Buy & use a roof rake !! Even if you can only clean 2' or so in from the edge. The sun will warm the metal and/or shingles up enough to melt the rest of the snow and your 2' cleared area gives it a place to go w/o causing "ice dams". I would not advise any inexperienced person to get on the roof.