Can I use chimney pipe instead of stove pipe?

[kimali]

We just bought a small wood burning stove off of Craigslist to use in our little (200 sq ft 'cabin') as well as 15 ft of class A stainless steel chimney pipe. We're wondering if we can use the chimney pipe for the whole shebang--meaning letting it sit on the 6" outlet from the top of the stove and running it through the cathedral ceiling. Also, other than adjustable flashing for the exterior, what else do we need for a safe install? Our little place is 'off-grid' and off the radar in terms of having to pass any inspections, but we would like it to be functionally safe.

 

[jtp10181]

You can do that, one of the members here has done this and posted pictures at one time. At the ceiling penetration you will need a trim ring so you can have your 2" clearance around the pipe, and then cover the hole with the trim ring. You will also need joist support brackets to support the weight of the chimney in the attic or right under the roof, it should not be supported by the stove. Not sure if you will get a good connection with the class A right on the stove (will have to test it), so you might need to adapt to single wall right before the stove and use a short piece of black pipe. You want the final connection to crimp and fit INSIDE the stove collar, if it fits outside you can get creosote leaking out around the seam and onto the stove, this is why they call the inside fit crimp on stove pipe a "drip-less" connection.

 

[kimali]

Many thanks for the great advice, especially regarding the fit around the stove collar--now I understand what drip-less means--I was wondering what that meant! I'm pretty certain the chimney pipe we bought is manufactured by Selkirk, so we're busy trying to track down the correct parts (flashing, universal roof support assembly, and the chimney pipe adapter). I wish I could look at pictures of someone else's install to give us a better idea how it all fits together and still looks nice. Although I *think* we've sussed out how it's all supposed to look on the exterior, the interior finish work has us a bit puzzled other than keeping a 2" space between the pipe and any insulation. We have no ceiling per se and our roof is pitched and is simply old-school tongue & groove fir about 1" thick plus the composite shingles. We'll eventually put in some insulation--most likely foil-foam-foil--then create a ceiling in bead board or drywall, etc. Since the exterior of the pipe measures 8", do we make basically an 8" cut in the roof?

 

[summit]

a factory made pipe adaptor specifiv per your insulated chim of choise should fit inside yout stove's collar. that being said, if you have a run of stovepipe going to the chim, you will achieve more heat return, and a less expensive install. unless you are going for the stainless steel look...

 

[kimali]

The 'cabin' and I use that term loosely, since 'shack' might be more apt, is only 200 sq ft--the stove is very small, but still large enough to keep it well heated so we aren't too concerned about maximizing the heat return. Plus, I think this way we can put it within 8" of the wall rather than 18 since floor space is pretty tight. We bought the 15ft of chimney (including cap, support brackets, and storm guard) for $200, so we went with all stainless not so much for aesthetics, but because we're trying to redo this cabin on a tight budget and using mostly salvaged goods when we can.

 

[jtp10181]

The 18" clearance is for single wall pipe, there is also double wall black stove pipe available, FYI. You don't have to use Class A to get the reduced clearance.

Also, the pipe is 8" on the outside, it needs a 2" air space clearance all the way up so you need a 12" hole in the ceiling / roof.

PLEASE look for an install manual on the Selkirk web-page and read it thoroughly. It should also go over the various parts you need for a legal install.

 

[kimali]

No worries, I'm studying the Selkirk manual right now...it's just that I'm very much a novice so I just want to make sure I'm interpreting everything correctly. We only went with the stainless since it was cheaper to buy this set of lightly used class A pipe than new black double-walled stuff. But since it's not common to do it, there isn't much on the web specific to using the class A pipe for the whole system and having such a low rent roofing system specific to the cabin itself doesn't help much either. Thanks for all the help!

 

[Highbeam]

Olympic Peninsula? Welcome neighbor. I grew up across the hood canal on the Kitsap peninsula. Double wall interior pipe may be more expensive but will relieve you of trying to figure this out. Are there any ceiling rafters at all or is it simply the roof rafters that you are attaching this to?

 

[kimali]

Well, how do neighbor! Our cabin is out in Brinnon and looks out across Hood Canal. The cabin is an old homestead we moved from Tacoma out to our property. It's been a bit of a project getting it in shape for weekend camping, but it's lovely out there. Hopefully with a wood stove we can do more camping earlier and later in the season than what we've been able to do so far. The kids need a place to warm up and get out of the rain!

I spent late last night sussing out the Selkirk and Duratech manuals and I "think" I've got a plan. The roof joists are 20 on center and the roof at the moment consists of composite shingles, roof felt, and 2x6 t&G;fir. Eventually we'll add a layer of insulation (foil-foam-foil), then a pitched ceiling of bead board or something to that effect. So all in all, the eventual celing will only be about 5-6 inches deep, if that much.

From what I've learned from you all and the guides, I need to make a 12" hole in the ceiling (much to the anxiety of my husband), fit in the pipe through Universal Roof Support Assembly (URSA), add some flashing and I'm good to go given the parts I already have. At the stove pipe, I need a short adapter piece (dripless--thanks for that info jtp10181). The stove came with a flimsy 20" piece of single wall pipe with a damper--I'm thinking I can snip that piece down to a about 10", fit it in the adapter and then attach it to the class A pipe. Voila, right? I'll make sure to have my giant sized fire extinguisher on hand when I get brave enough to make my first fire.

We have about a 1" thick piece of granite remnant that we thought we'd sit it on instead of the old wood floor. As for the finish work on the roof so we don't have to look up into the flashing, I think we'll try to fabricate our own ceiling plate out of some 22 gauge steel we have from the old shower stall wall. Sound like a plan?

I'm guessing with the roof joists being 20 O.C., we'll have to frame in some support studs that the URSA can rest or--or is it supposed to just rest on the roof itself? No pictures in the manual to adequately explain the install, but perhaps that comes when you order that Part? That is, if I can find somewhere to buy it. Ace Hardware only sells the whole roof support package and we don't need that since we already have the pipe.

Any thoughts out there on if we need a heat shield on the two walls if we tuck this into a corner? We'll keep the stove about 8" away from the walls, but I'm wondering if I need a barrier still. We thought we'd using our metal sheets we have (again from an old shower stall), and mount those 1" from the wall with some spacers. Any thoughts?

 

[firefighterjake]

. . .
We have about a 1" thick piece of granite remnant that we thought we'd sit it on instead of the old wood floor. . . .Any thoughts out there on if we need a heat shield on the two walls if we tuck this into a corner? We'll keep the stove about 8" away from the walls, but I'm wondering if I need a barrier still. We thought we'd using our metal sheets we have (again from an old shower stall), and mount those 1" from the wall with some spacers. Any thoughts?

To be safe you will want to find out what the R value requirements for this stove are . . . if there are any. Granite would provide ember protection, but may not offer a lot of R value if the stove has a high R value requirement for the hearth. Since you're off the proverbial radar you don't have to worry about inspectors, but over here in my neck of the woods the Inspector would require some sort of listed floor protection for the hearth (i.e. Durock) even if the stove only required ember protection.

As for the walls and distance . . . again, what is the stove's requirements? Some stoves allow pretty close clearances . . . some can be reduced further through optional heat shields or by fabricating heat shields per NFPA 211 guidelines. If you can't find clearance requirements for this stove you resort back to the 3-foot rule . . . although, again, this distance can be reduced somewhat by fabricating wall protection devices per 211.

 

[jtp10181]

If you use the single wall pipe you will need that pipe to be 18" (I think?) from any combustible surface (drywall, studs behind the wall... etc).

If you use double wall pipe you can get everything much closer into the corner for most stoves.

BTW what make a model stove did you get? You never did say. I hope it has a rating plate on it listing install clearances and some sort of testing agency approval.

 

[kimali]

The stove is made by Timberline (with a CA address) model T-24 T-18--I can't find any info on the company or anything more about the stove. It does have a sticker on the rear heat shield that says the non-combustible floor covering must be a minimum of 3/8" thick and must extend 8" from the sides and 16" front and back. The stove has heat shields on the back and on the bottom. It stands on ball casters and is approximately 15.5 " wide x22" deep (not including rear heat shield or a threshold below the front door) x 29" tall. When you include the rear heat shield and the threshold it's about 31" deep.


There is a diagram on the sticker that says if it's put in the corner there should be a 36" clearance from the center of the stove pipe (I'm assuming they are assuming it is single walled).

So...I'll be using single walled stove pipe for the first 15" or so, then will switch over to the Class A stuff--that is unless anyone feels I don't need the damper. In that case I could just run the class A pipe directly from the stove with a small adapter to get a good seal.

 

[jtp10181]

The 36" clearance is probably from the stove body itself. Any "unlisted" stove must follow the generic NFPA 211 clearances which is 36" clearance to combustibles all the way around. So.... you might want to re-think that 8" you were mentioning earlier.