Drolet Spark Alcove

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New Member
Nov 19, 2021
Hello, I’m a new homeowner and wood stove user in Ontario. I have some questions about a drolet spark alcove installation. Firstly The alcove construction is in the basement, concrete block foundation, then steel studs, roxul insulation and 6mm poly and durock board. I would like to finish the walls with brick at a later date.
My understanding is that these materials classify as non combustible, so what do I measure my clearances to as far as required by home insurance?
The stove pipe is double walled up to the ceiling with a sticker on the back that says 6in clearance. Then through the roof to a chimney that has a sticker that says 2in clearance.
The chimney isn’t centred in the alcove so the distance from the side of unit on one side to the durock is 8inches. The appliance states 18 inch clearance can be lowered to 9 inches with a shield.
I suppose my question is, is the 8 inches okay? Because there are no combustibles? Or is it still too close? I was concerned the heat on the concrete board would transfer to the steel studs then up to the roof joists(wood). I’m sorry if this is confusing I can answer any more questions and get pictures if needed. Thanks!
The 6mil poly is combustible. If the alcove has not already been built, eliminate it from the alcove construction. If it has been built, unscrew the Durock (label the sheet positions) and cut it out. Then the clearance issue to the walls is moot. At that point the entire enclosure is non-combustible.

What is the ceiling height of the alcove? If it's greater than 72" then it is ok. Heat transfer will not be an issue. At the ceiling support box it transitions to Class A chimney which will require at least 2 in. clearance all the way up through the roof.
I can remove the poly, the ceiling height is 94 inches. Thank you for the response I thought I was understanding everything properly but had my concerns especially around a wood stove.
You're good then. Clearance requirements only apply to the nearest combustible. Without the poly there is nothing combustible. I'm glad you asked before the brick veneer went on.
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