Help with double wall stove pipe to masonry chimney.

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New Member
Sep 21, 2022
Vermont, USA
Hi, all. Please forgive my lack of knowledge. We just had our chimney lined for a wood stove connection, and they installed everything to the 6" stainless pipe coming through the hole in the chimney (thimble I guess this is called?) We have a Drolet Escape 1200. I am at a loss as to what all I need to go from the Stove to the chimney. I have laid out the path in Sketchup (cause it's going to be a little wonky and I wanted to make sure it would work). It looks like I am going to need two 45degree elbows, and two straight pieces. One approximately 12" and one approximately 13". We are doing double wall pipe for clearance reasons. I have been shopping on line and trying to research how to do this, since I can't cut the pipe and it only comes in increments of 6" lengths. I have come across "slip connectors", but can't find a good explanation of how much length they can add to pipe. Ie. If I buy a 6" x 6" slip connector, does this add up to 6" of length? Does it add 6" or more of length? On one website, it says the 6" x 6" slip connector is 6" and has an adjustment amount of 2"-4". Does that mean it can add 2-6" of length to the pipe? Or....what does this mean? I even asked one retailer via their chat, and they simply told me to read the Ventis manual (which does not contain this information) or contact the manufacturer, but I couldn't find Ventis contact information.

Does anyone know the simplest way to extend a 12" double wall black pipe to ~13"?

Also, can someone tell me what the built in wiggle room when connecting these pipes is? Ie. If the pipe that i have calculated out at 12" needs to actually be 11.5" when I go to install is there wiggle room to make it fit somehow? Or do I need to go for a 6" pipe with something like a 12" slip connector?

Basically, I am not totally grasping how to order the parts and make sure they will fit properly.

Also, if there are part I am missing? Do I need some sort of adapter to go from the double wall pipe to the stainless pipe sticking out of our chimney? Do I need an adapter to fit the double wall pipe to the stove exhaust?

Total newbie, please help, and explain it like I don't know anything about double wall stove pipe. (picture of current chimney connection (don't mind the vegan jerky box taped over the opening, I have a large fear of bats in my house), and drawing of the planned pipe run from stove to chimney...for reference)


Chimney Connection.jpg Stove Pipe Run.png


Minister of Fire
Feb 16, 2014
look up telescoping double wall pipe by the same manufacturer, so your going to want to come out the thimble (need an adapter) to dvl then 45 down, then straight piece of pipe, then 45 to the telescoping piece, terminate the telescoping piece into stove collar adapter which then goes into the wood stove's stove collar (stainless steel)
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