As usual for my questions, some weird twists: in this case litterally.
Best attempt at condensed version of story:
Last summer the FIL brought us a very nice wood stove to put in the [stand alone] garage. I bought several lenghts of 6" black pipe and a few of double wall SS to install it; and am finally getting around to it.
The garage had a stove [long before my time] piped out with a hole in the ceiling [simple ship-lap type floor on very simple attic; no inside covering of the studs on ceiling, roof, or walls] and straight through the roof (all in single wall judging from the pipes laying in the attic!). This had been shingled over and now tinned; I hate running stove pipe through ribbed tin - I successfully done it once before, but still hate trying to seal around the rib.
The attic window needs to be rebuilt anyway, so I like the concept of going through that. However, it would take a 2ft up and 2 ft over run to get from my ceiling thimble [homemade, but, I'm quite confident, safe] to the window. Now the question: AFAIK double wall isn't available in anything but T's [and maybe a 15degree angle] and straights, so I'd be throwing something like 4 Ts and a couple straights just in the attic vs. a flex on each end of a 3ft black. Does that make sense over the black? I know cheap compared to a fire, but the double wall runs about 10X the price of black so it makes one ponder. Also, I'm not sure that that much double wall twisting around is much safer than a simple run of black (I think the smallest clearance would be around 12", maybe as low as 8" at the elbow, varying up to 3' floor and ceiling and 12" to the wall). I have plenty of tin around yet so I could give the studs and wall a bit of protection, perhaps attaching tin spaced an inch or two off the studs.
Other options:
Running the black across under the ceiling, but now I have 3ft at only 1ft clearance under the ceiling on its entire run or the risk of wacking my head on hot stove pipe. Still would need additional double wall and double wall T.
Going straight out the wall either in the attic (still would have a point of clearance less than 18" on the elbow or an additional double wall T) under the ceiling, but with the size of double wall the thimble gets so big I don't relish trying to seal the siding much more than the roof.
Of course, straight out the roof.
Why must I complicate things so?
Best attempt at condensed version of story:
Last summer the FIL brought us a very nice wood stove to put in the [stand alone] garage. I bought several lenghts of 6" black pipe and a few of double wall SS to install it; and am finally getting around to it.
The garage had a stove [long before my time] piped out with a hole in the ceiling [simple ship-lap type floor on very simple attic; no inside covering of the studs on ceiling, roof, or walls] and straight through the roof (all in single wall judging from the pipes laying in the attic!). This had been shingled over and now tinned; I hate running stove pipe through ribbed tin - I successfully done it once before, but still hate trying to seal around the rib.
The attic window needs to be rebuilt anyway, so I like the concept of going through that. However, it would take a 2ft up and 2 ft over run to get from my ceiling thimble [homemade, but, I'm quite confident, safe] to the window. Now the question: AFAIK double wall isn't available in anything but T's [and maybe a 15degree angle] and straights, so I'd be throwing something like 4 Ts and a couple straights just in the attic vs. a flex on each end of a 3ft black. Does that make sense over the black? I know cheap compared to a fire, but the double wall runs about 10X the price of black so it makes one ponder. Also, I'm not sure that that much double wall twisting around is much safer than a simple run of black (I think the smallest clearance would be around 12", maybe as low as 8" at the elbow, varying up to 3' floor and ceiling and 12" to the wall). I have plenty of tin around yet so I could give the studs and wall a bit of protection, perhaps attaching tin spaced an inch or two off the studs.
Other options:
Running the black across under the ceiling, but now I have 3ft at only 1ft clearance under the ceiling on its entire run or the risk of wacking my head on hot stove pipe. Still would need additional double wall and double wall T.
Going straight out the wall either in the attic (still would have a point of clearance less than 18" on the elbow or an additional double wall T) under the ceiling, but with the size of double wall the thimble gets so big I don't relish trying to seal the siding much more than the roof.
Of course, straight out the roof.
Why must I complicate things so?