Steel thickness, seams and strength

Hi Guys, Great site! Here in New Hampshire, we had between 3 and 4 feet of snow on the ground at one point this winter (2 feet at any given point during the winter is common). For snow and ice shedding, I'm considering a metal roof. I've had trouble with ice damming (no referred to as damn ice), and reinsulating and venting has not entirely cured the problem. 1. Does the material typically come in overlapping sheets or contiguous peak to eve lengths? 2. Does it typically come in different thicknesses or gauges? 3. Can it be walked on? There is a full dormer in the back of the cape style home that is fairly shallow pitched and may serve as a standing point for mason should the chimney require re-pointing. 4. How are the sheets seamed together? Is one seam better than another in my climate in terms of snow and ice shedding?

There are a wide variety of metal roof styles available today. These do include various gauges and metals. Some products\are run continuous from ridge to eave whereas others come in sheets and the shingle and tile look products run horizontally. Metal roofing can be walked though, with certain products, you may need ot walk in ncertain areas on the roof. Some of the shingle style products have rigid foam backers available for additional walkability. Some panels overlap and some have actual interlocks. I would suggest choosing some products you might like and then talking with the manufacturers to discuss their suitability for your application and your climate.