Cathedral ceiling, block wall behind stove, ice damming on roof
Glad to be here and have read a GREAT deal and learned a TON on this site already. Fantastic info.
Some quick facts…. (central NY,,very snowy area)
-Home is contemporary style. Very high cathedral ceilings.
-28 yrs old. Roof is 5 yrs old.
-Owned home for 2 winters – same issues each winter
-8″ rafters, 1″ of closed cell foam boards against sheetrock, gap, then foam baffle against roof. Cool, vented roof setup.
The issue: I’m getting ice dams because snow is melting from 3-4 sections (rafter spacing widths) of section. My suspicion is that the block wall and/or chimney pipe is leaking hot air causing the roof to warm.
I have a pellet stove that we run all winter. It warms a block wall 7′ long and 1 block deep that is in a central area between the kitchen and dining room. It is its own wall. This block wall goes into the cathedral ceiling and I cannot confirm how it is insulated once it disappears into the ceiling.
The 6″ pipe going into the ceiling should also be insulated and sealed but can’t confirm how without ripping out the sheet rock.
I have another identical cathedral ceiling in the home without the block wall and I get zero ice damming. I also have an attic roof line space that gets zero damming.
My next steps:
Verify soffit is not clogged and each rafter space is getting ventilation. I know they are getting some air because the snow melts as if warm air is coming out the ridge vent.
Break sheetrock around block wall to inspect for proper insulation? I’m really not sure.
Please see the attached thermal images using a Fluke Ti25. One of the benefits of working in a shop is that you can borrow the toys. All of the images are of the same space with different detail to help with clarity.
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