Wood stove installation and exterior foam board insulation
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If I want to install a wood stove through the wall or the roof and both have 6″ of foam board on the exterior, are there additional precautions to prevent exhaust heat duct from melting or causing a fire around the insulation? For example, install one or more layers of cement board over the 6″ of foam. Then install through the wall or roof duct work.
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Download the catalog and installation instructions for the flue pipe system you're going to use, choose the parts that will work, and install them exactly in accordance with the instructions. Do not use anything that is not a part of the pipe system. Clearance to combustibles applies regardless if the material is foam, wood, or whatever. Foam may require protection but this is NOT addressed by the pipe system manufacturer, it is part of building code and needs to be researched separately. Your building inspector might be able to help with this, and/or the supplier of the woodstove or vent parts. A wall thimble or similar fitting might do what you want to do.
Putting a material like cement board over combustible material does NOT make it non-combustible--that term refers to things like concrete block, solid concrete, brick, etc. If you have wood framing, you're never going to have non-combustibles.
AJ, are you stating that Roxul is acceptable protection for foam, and is needed? The guy has barely posted a single detail of his installation.
The foam is cut back, Roxul fire batt replaces it, metal flashing, done with a certified insulated chimney flue pipe installer and proper fire inspection from your local fire authority.
David gave you good advice.
David, not interested in debating my posts with you. Thank you.