Sometimes there is a fear of flat roofs, especially in heavy snow areas. I would like to nix that fear right now. First of all, there are no flat roofs, only low sloping roofs. All roofs nowadays are constructed with enough slope to direct water off the roof. Yes, in the early part of the 20th century, many modernist buildings and international style homes had roof leaks that led to structures damaged beyond repair. However, consider this: most commercial buildings have low sloping roofs: hospitals, grocery stores, skyscrapers, airports, shopping malls, strip malls, etc. After a century of building this way, I feel pretty confident in our ability to control water drainage and waterproofing on low sloping roofs. Some will say that a flat roof looks great on a sleek modern home design in the city, but that it can't possibly work for a cabin in the snowy mountains. To this I would direct you to a quick google search of glass box homes in the Swiss Alps often with 5' or more snow on their "flat" roofs. In fact, holding the snow on the roof throughout the winter adds insulation to the top of the home and reduces snow piling up in roof valleys or against residence walls that were not designed for so much extra load. If a modern home with large spans of glass, and a thin roof slicing through the trees is what you want, don't be afraid of low sloping roofs.