Connecting double wall pipe to single wall T - who’s telling me the correct info?

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KennyK

Feeling the Heat
Oct 26, 2011
351
Boston
Hi all,

I have a short horizontal run from the rear of my Fireview that connects to the single wall T that comes off my flex liner. The horizontal run has to be double wall to make clearances with my wood mantel. The person who connected my prior stove crimped the end of the snout of the T and the double wall pipe fit around that. A chimney sweep was here the other day and told me that was done incorrectly and that I need a converter/adapter piece to go from the single wall T to double wall horizontal pipe. I called Selkirk (who makes the double wall pipe I have) and they said that it was fine as it was done, and that the snout didn’t even need to be crimped and it would fit just fine and be done correctly (I may need to cut the snout back a couple inches to fit my new stove, so I was wondering if I would need to crimp it again). I called Woodstock (who sold me the Selkirk double walled pipe) and they said that it was done right and that the single walled snout would need to be crimped to fit into the Selkirk double wall pipe. Who’s correct here? Do I really need some sort of an adapter to connect the single wall snout to double wall pipe as the chimney sweep said? If not, does the single wall need to be crimped to fit into the double walled pipe, as Woodstock said? Or, can I fit the double walled Selkirk pipe around the snout without crimping? Pictures attached if that helps illustrate.

Thank you!
 

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It looks like what you are doing is correct. Selkirk double-wall is confusing because there is an inner liner crimp on one end and the outer liner crimp too.

Did anyone mention that this also could be done in single-wall with a section of pipe shielding on the horiz. section?
 
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I’ll start by saying I HATE that double wall pipe! Although, it’s safe enough..
The tee snout often needs crimped, there’s nothing wrong with that, it’s normal. You’ll just have to try it when the time comes. Your chimney sweep is a typical “inspector” he knows a little about everything, but very little about most stuff.
 
Yes, not my favorite either.
 
It looks like what you are doing is correct. Selkirk double-wall is confusing because there is an inner liner crimp on one end and the outer liner crimp too.

Did anyone mention that this also could be done in single-wall with a section of pipe shielding on the horiz. section?
Thanks! Yes, as you described is exactly how the Selkirk double-wall is. Is other double wall pipe different? From what I could tell, the Selkirk may have the closest clearances of all double wall pipe at 6."

Regarding if anyone mentioned that it could also be done in single-wall, as I wrote in my original post, "The horizontal run has to be double wall to make clearances with my wood mantel." If I'm not mistaken, single wall requires 18" to combustibles and I don't have that.

Thanks!
 
I’ll start by saying I HATE that double wall pipe! Although, it’s safe enough..
The tee snout often needs crimped, there’s nothing wrong with that, it’s normal. You’ll just have to try it when the time comes. Your chimney sweep is a typical “inspector” he knows a little about everything, but very little about most stuff.

Thanks! What is it that you "HATE" about double wall pipe? Just curious...
 
Thanks! What is it that you "HATE" about double wall pipe? Just curious...
It’s that particular pipe. The fit and finish is pretty bad, it’s really hard to use compared to most all other brands.
 
Thanks! Yes, as you described is exactly how the Selkirk double-wall is. Is other double wall pipe different? From what I could tell, the Selkirk may have the closest clearances of all double wall pipe at 6."

Regarding if anyone mentioned that it could also be done in single-wall, as I wrote in my original post, "The horizontal run has to be double wall to make clearances with my wood mantel." If I'm not mistaken, single wall requires 18" to combustibles and I don't have that.

Thanks!
All the double wall I’ve used was 6” clearance.
 
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I think all double-wall stove pipe has a side clearance of 6" when installed vertically. The clearance above double-wall when installed horizontally can vary with the manufacturer. Excel, Security and Selkirk say 6". DuraVent and Ventis say 8".
 
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It’s that particular pipe. The fit and finish is pretty bad, it’s really hard to use compared to most all other brands.
I think all double-wall stove pipe has a side clearance of 6" when installed vertically. The clearance above double-wall when installed horizontally can vary with the manufacturer. Excel, Security and Selkirk say 6". DuraVent and Ventis say 8".

Thanks @begreen and @webby3650! Begreen, I miss-read your earlier post about using single wall with pipe shielding. That’s a thought. Any advantage to that over double wall? Is it also a 6” clearance if on a horizontal run? I’ll probably stick with the double wall Selkirk as I already have it, but it’s good to know these things.
 
Thanks @begreen and @webby3650! Begreen, I miss-read your earlier post about using single wall with pipe shielding. That’s a thought. Any advantage to that over double wall? Is it also a 6” clearance if on a horizontal run? I’ll probably stick with the double wall Selkirk as I already have it, but it’s good to know these things.
Rockford says 6" to the wall and 9" to the ceiling for their single-wall shield.
 
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