It kind of depends on the age of your roof, the roof materials and the pitch. So i live in an old farmhouse with a 1.5 story setup, back when we had a shingled roof, snow wouldn't shed off of it, then if there was a fair amount of snow 2-3 feet it would pile up on the roof. Then ice starts to form underneath the snow from the heat of the house. Plus then sometimes (like as I'm typing) it rains, all that snow and ice on the roof soaking up water can get heavy enough to make an older roof sag especially on outbuildings. Also with the freeze thaw on a shingle roof it shortens the life of the shingles. Now we have a standing seam metal roof, the snow sheds right off and I never think about shoveling my roof again.

Ice dams can form on roofs. They can cause serious interior flooding damage. I speak from experience. My older (1880) house had multiple eaves and levels and I had a waterfall come into my kitchen one evening due to an ice dam. Shoveling snow prevents them from forming.

I have standing seam so I don't do anything to the snow, it just slides off on it's own.

Many houses in Vermont are quite old, and were built before insulation existed. This meant that during the winter, the heat from the fire would heat up the roof and consistently encourage the snow to shed. The rafters were at most designed to carry the weight of the slate, but snow was not really considered an issue due to this heating effect and the steep pitched roofs. After insulation and air sealing became widespread in the 1950s, people began to became more concerned with the snow load, since the roof remained cold and the snow did not shed as readily. That is why now many people with old houses have to be careful in the winter to remove excessive amounts of snow from their roofs. Hope this helps!

Greetings from VT. I love Tucson...spent a week there last April and had a blast. It depends on how much moisture is in the snow. Light, fluffy snow is no problem, but when the snow is heavier (i.e. wetter), it's a good idea to get the snow off the roof. Especially if you live in an old house. Our building stock here is OLD.

You definitely want to remove heavy wet snow from flat roofs or roofs that don't facilitate it sliding off (such as a shingled roof, or one with too low an angle). Standing seam roofs solve the issue. I still remember how giddy my mother was when we had one installed when I was a kid - she HATED roof raking.

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The folks who retreat to AZ and other warmer climes for the winter are likely to fall into one of two camps: either they have a standing seam roof so the snow slides right off, or someone else takes care of it for them while they're gone (whether a paid third party or groundskeeping/maintenance if they live in a condo or something).

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Oh boy it’s civil engineering time! Areas around the world have a “snow load” value much like being in a specific seismic zone. In Vt some places have snow load requirements of 70lb/ft2!! For a small house this can easily get to over 20,000lb of load. So yeah, the house should be designed for it - but most houses here are pretty damn old.

Hey fellow tucsonian! This question reminds me of how important having a slight slant in our az roofs was. If your roof didn’t have a small angle, the water would pool up and lead to leaks. Here, some roofs will drop it naturally, but others benefit from some “encouragement.”

One problem is clearing any vents to monitor heaters that may be on a 2nd floor or vents for your plumbing. Vermont's housing stock is very old and with that, there are houses that do not meet today's standards. Also several generations have done diy repairs that aren't up to handling tons of snow. My house is in that category.