I need to run a woodstove pipe through a cathedral ceiling to the outside and have never done this before. So, I'm looking for some advice on particular methods/products.
The stove is in a small cabin with a cathedral ceiling and exposed timber rafters. The pipe will pass through the living space, between the rafters and through the interior sheathing (shiplapped pine), through a 12" cavity of dense-packed cellulose, then through the exterior sheathing (1/2" plywood), and out the metal roof.
Does the pipe need some sort of structural support as it passed through the ceiling (MetalBest has a product thats a double-walled pipe with metal "wings" that screw into joists or blocking)? If so, what products to people recommend (particularly, whats cheap?)?
How can I isolate the pipe from the dense-pack cellulose around it (which hasnt been blown yet)? Some sort of shield?
Dan, I strongly urge you to pay an NFI Certified Professional to plan and install this stove. There are so many things you need to know about it they made a whole certification course on it. You must use ALL the listed components specified by the mfr the way they specify. This includes the attic insulation shield, supports, bracing, roof flashing, rain cap, etc. Usually a cathedral ceiling support box is used, which projects down into the room the requisite distance so you pipe has clearance to the combustibles nearby.
Also part of the installation is the stove pad and shielding. If it is an unlisted stove, I strongly recommend you cancel the project until you can afford a cleaner burning stove certified to EPA Phase II standards. Such a modern stove is also much more efficient than old clunkers. The new stove will likely have reduced clearances to combustibles, which may allow you to place it closer to walls thus freeing up some floor space. The size, location and typ of floor and wall protection are specified by the listed instructions for the stove. If it is an unlisted stove, your default is NFPA 211.
Note that DIY woodstove installs have a vastly higher incidence rate of unfriendly fires than those installed by qualified professionals.
www.nficertified.org for the pro nearest you. In Canada, you'll need a tech who is WETT Certified.