I have an old Centennial wood stove on the second floor of my house. At the ceiling, the black stove pipe goes through a collar and the stove pipe turns into double wall stainless steel. On the third floor the s/s stove pipe is enclosed in an uninsulated drywall and stud chase. The stove pipe then enters the attic. There is no collar preventing air from the pipe chase from entering the attic. There is only about a foot or two of stove pipe in the attic because the third floor has a cathedral ceiling and the chimney is located near the eave. The s/s stove pipe emerges through an exposed-screw steel roof. The steel roof sits on 1X4" pearlings which sit on half-inch plywood decking. The attic is well insulated. The roof has a 6 and 12 pitch. The attic has ridge vent, sofit vent and gable vents. When we use the wood stove in winter, it heats the attic and steel roof. This melts the snow, turning it to ice. When the weather warms, we get tons of ice sliding off the roof and bashing dents in a porch roof down on the first floor. These slabs of ice take the chimney with them. I tried using a snow diverter, but the ice took it too. (I have patched the hole in the roof where the chimney came out and if I were to give it one more try with the snow diverter, I'd use bolts instead of wood screws to hold it in place.) I've looked into installing snow breaks on the roof to keep it from sliding. Last year we had a record snowfall which would have needed shoveling if we didn't have a self shedding steel roof. I'm not crazy about shoveling a 6 and 12 steel roof which is 30 feet off the ground. When we don't use the wood stove the snow slides off the roof more or less as snow which does not damage the porch below. It just fills our yards with snow berms. (The ice could easily kill someone if they were standing there when the ice comes crashing down.) My ideal solution would be to move the stove to the center of the houses so that it exits the roof near the ridge. I might also move the stove to the first floor to better heat the house. It seems to me that the drywall and stud pipe chase should be sealed at the attic to prevent heat loss. I heard that this would be against code. In winter, the existing drywall pipe chase wall is cold and moisture condenses on it because cold air from the attic is allowed to to come down the case. At the least, I think the drywall should be insulated. While you're at it, why not build an insulated pipe chase around the double wall stove pipe in the attic to prevent heat from entering the attic. I guess the contractor who put the steel roof on wanted to keep it cooler by putting the steel panels on 1X4 pearlings--thus allowing cold airflow between the steel panels and the plywood decking. This would work if it were not possible for heat from the pipe chase to enter this 3/4 inch gap and be distributed over half the roof. If I were to leave the stove where it is now, I should at least spray a foam seal in a circle around the hole where the stove pipe comes through the roof. The foam would go between the steel roofing and the plywood decking. Does anyone have any suggestions on how to fix this bad design problem?