Insulation Around Gas Water Heater Flue-Updated Question with Photo
**Update: I discovered that I do have a fire stop on the underside (main floor ceiling) of the water heater flue. Am I good to go with the Roxul butted up against the B vent without any further modifications? I have used some high temp caulking around the circumference of the vent on the attic side.
A Canadian Government publication indicates the fire stop can be on the underside of the attic floor. But they do not discuss the use of mineral wool specifically, just that no “combustible material should touch vent”. I remember reading that Roxul may not be approved for direct contact with B vents, but then read that approval may be different in Canada.
The Ontario Building Code is like a different language to me. Can anyone clarify?
Note: view of fire stop is upside down…that’s a view looking up.
This is for a vented, unfinished attic.
I just want to be sure of something: I asked a question last week about insulation around the gas water heater vent penetrating ceiling and roof deck in the area in which the baffle would sit.
I sealed off the venting in this bay, but now I must surround the vent with Roxul (fire-rated material) because foam can’t be used within several inches of vent. The Roxul will have contact with the roof deck because, as I understand it, the foam baffle to protect the roof deck can’t be used. I just wanted to be sure this was okay, as it seems that Roxul is not recommended to have contact with concrete or wood in crawl space applications.
in Southern Ontario
in a Vented Unfinished Attic
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