DIY chimney double wall ?

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Bra d

New Member
Sep 15, 2022
2
PA
New guy here! Running an older quadrafire 2100 I picked up for a couple hundred dollars. Due to the high price of double wall stainless I was wondering if is even feasible to DIY it by putting a 6" inside an 8" and wrapping the 6" with a ceramic blanket in between it and the 8" ?
Probably wouldn't pass an insurance inspection I know but aside from that are there any other issues to consider ? BTW the entire chimney will be free standing 24" away from the outside wall . The only protrusion is through a window I removed & filled with an aluminum plate . A DIY double wall horizontal about 4' long goes through that plate .
I did use single wall 6" the first year and didn't have much problem other than it was hard to start it smoke free . Was hoping double wall would give me a better draft faster at starup.
I will start saving for the factory pipe ,but current economy is preventing that.
 
No, that's not a good idea for many reasons. Stove pipe is only for interior use. It can not cross the room barrier. The inner jacket of chimney pipe is stainless and rated for wood use. The insulation is specially chosen to provide strict clearances. Then there is the issue of keeping moisture out of the insulation which would negate its properties and accelerate the degradation of the stovepipe. There are many more issues. Just get real chimney pipe and do this safely, please.

The long horizontal section is part of the issue. A short chimney might also be an issue. Using single-wall outside really cools down the flue gases and contributes to weaker draft as well as being dangerous.
 
Thanks guys . Guess i pretty much knew what answers would be .
My gas company just sent me a letter claiming my gas bill will be going up double from last years .
I was just hoping this would be acceptable for this one winter season while I save for the good stuff .
But, although its not what I wanted to hear - advice is well taken. Thanks !
 
The head of Exxon was on the news the other day, he said "although prices are dropping right now, be ready for inflated prices this winter" there are a lot of people around here with outside oil tanks, that means they have to mix with kerosene to keep from gelling up. Could be 6 dollars a gallon or more, yikes
 
The galvanized pipe exterior wall has worked for me for many years. It is stainless inside where it counts and made for inside of a chase protected from weather. The roof flashing and storm collar is the same gauge galvanized exposed on the roof and works fine with no rust, so I replaced my stainless outer wall with the cheaper galvanized.