I think I understand the mechanics of ice dams. Up until recentely they were
just an academic topic for me. I now own a home that is suglect to occasional
ice dams. Two occurances in the last 5 winters.

The roof is metal (standing seam?), dams (so far) have only occured in two
places on the ~south facing roof slopes.


Question............is this a design problem, construction problem or so they
just happen?

Is the solution something like Raychem heating cable?

Bob