Originally Posted by Shawner
What can I do
A switch with neon light mounted on the ceiling of a closet that bypasses your attic fan's thermostat so you can run the fan in the winter during the times that ice dams may form? The light goes on whenever the fan is running for whichever reason.
I wired this up one time when everyone around here was having ice dams for some reason, but I never got a chance to test it. If I get ice dams they don't leak into the house, that I can see, but others had their drywall damaged during that peculiar winter.
The choice seems to be to make the roof surface cold or the overhang surface hot. Or. . .maybe salt the overhangs after you confirm that this chemical fix won't damage the shingles.
Your being near a lake may make it worse.