Wood stove piping

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cric8192

New Member
Sep 19, 2023
3
Ontario
Hi,

I am trying to install a wood stove in an old post and beam barn with metal roof.

The location I’ve chosen will provide more than 18” of clearance for the piping inside the building so I would like to use single wall pipe for cost reasons.

My understanding is where it penetrates the roof, which is constructed of 1x12 with steel roofing on top, that I need double wall pipe. Once I’m outside and extending to the required height do I continue with double wall or can I switch back to single?

This is just a small workshop so I’d like to keep the cost down.

Thank you
 

neverstop

Feeling the Heat
Oct 11, 2020
300
new hampshire
you're going to need to use a ceiling support box to go through the roof and then above that you will need to use Class A chimney pipe
 

kborndale

Minister of Fire
Oct 9, 2008
841
LI
How long from stove top to ceiling? Double wall stove pipe does more than just reduce clearances, it keeps the flue temps warmer which gives you better draft and less creosote. If the run is longer than a few feet you should use double wall stove pipe.
 

begreen

Mooderator
Staff member
Nov 18, 2005
102,443
South Puget Sound, WA
How long from stove top to ceiling? Double wall stove pipe does more than just reduce clearances, it keeps the flue temps warmer which gives you better draft and less creosote. If the run is longer than a few feet you should use double wall stove pipe.
Exactly right. Many stove mfgs. recommend double-wall stove pipe to be used for runs over 8 ft. That said, single-wall will work but be sure to only burn dry wood and keep the flue temps high enough so that they exit the chimney cap at above 250ºF.

PS: Double-wall stove pipe is not the same as double-wall chimney pipe. Stove pipe can not be used outside of the room envelope. It is not designed or tested for outdoor usage.
 

cric8192

New Member
Sep 19, 2023
3
Ontario
Thank you for that information. The stove has a rear flue however as described I want to exit straight through the roof.

This is an older stove I can’t identify make or model but generally is it ok to have a 90 right off the back of the stove to go up? Or would you put a T so you have an easy clean out?
 

begreen

Mooderator
Staff member
Nov 18, 2005
102,443
South Puget Sound, WA
This is an older stove I can’t identify make or model but generally is it ok to have a 90 right off the back of the stove to go up?
Can you post a picture of the stove so that we can identify it? Some are easy to clean from the inside of the stove, some are not.
 

cric8192

New Member
Sep 19, 2023
3
Ontario
3EA65D58-8311-4E19-9AB5-7B6935F83A28.png

It says crafted made in Barrie Ontario but I couldn’t get anything to come up online. There is a baffle plate of some sort that runs on an angle blocking access to the outlet from inside the stove.
 

begreen

Mooderator
Staff member
Nov 18, 2005
102,443
South Puget Sound, WA
I'm not sure but that looks like an old insert that someone put legs on. Has this been approved by the local inspecting authority and insurance company?
My guess is that it has just a simple baffle if any. If so, no need for a tee on the flue.
 

zak77

New Member
Oct 24, 2022
50
MA
I dont think it'll matter whether you use an elbow or a T, although the T will allow easier cleanings of the flue.
 

begreen

Mooderator
Staff member
Nov 18, 2005
102,443
South Puget Sound, WA
I dont think it'll matter whether you use an elbow or a T, although the T will allow easier cleanings of the flue.
If there is a baffle and it's not welded in, then no need. Just drop the baffle and clean.