Stove pipe vertical to horizontal ratio?

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IowaHuntr

New Member
May 22, 2022
22
Iowa
Hello all, me again, so I am trying to make sure I cover all the bases as I replace my wood stove and upgrade pipe and thimble. My question is, is there a rule of thumb as to how long your vertical run out of the stove should be in relation to the horizontal run into the chimney? My previous stove had a 14” vertical, 90 degree elbow, and then 30” horizontal into chimney. Previous owner mentioned draft issues( which could have come from a number of other things). The stove I just removed from another house had 22” vertical, 90 elbow, and then approx 46” horizontal into exterior pipe. I can only assume that it worked for them. I am contemplating cutting a new flue hole higher up in my chimney for my new install if it is rational. I could make new hole 2 feet higher and still retain proper ceiling distance. Boring an 8” hole through brick chimney and clay liner will be no easy task but I am willing to do it if it may help with draft. Can’t find any real guidelines on the web. Thanks in advance for any insight!
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
I am installing a Vermont castings Defiant II. The installation manual does not say anything about pipe lengths. The manual ( as well as every web search I do) only talks about distances from combustibles.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,460
central pa
The most important thing is overall chimney height and size
 
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bholler

Chimney sweep
Staff member
Jan 14, 2014
28,460
central pa
What is your current chimney height size condition etc?
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
The most important thing is overall chimney height and size
What is your current chimney height size condition etc?
This is my current chimney. 8 x 12 clay liner approx 16’ tall. ( probably 10-12’ above stove pipe entrance) Top has a metal “cap” which reduces to 8” round. I think I need to add about 4’ of insulated 8” pipe to the top to comply with 2-3-10 rule. This chimney was used with a wood stove for 20 years just as you see it now.
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
What is your current chimney height size condition etc?

794751BA-8603-4694-8206-319B16DCC4B1.jpeg
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
I am replacing this wall behind the stove so now would be the time to relocate flue entrance if it will be worth the effort.

5AD261D8-EA86-46DF-9CCB-7A556FA7F727.jpeg
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,460
central pa
This is my current chimney. 8 x 12 clay liner approx 16’ tall. ( probably 10-12’ above stove pipe entrance) Top has a metal “cap” which reduces to 8” round. I think I need to add about 4’ of insulated 8” pipe to the top to comply with 2-3-10 rule. This chimney was used with a wood stove for 20 years just as you see it now.
Have you had the chimney inspected by a chimney pro? If it were mine I would be installing a liner and moving the crock up
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
Have you had the chimney inspected by a chimney pro? If it were mine I would be installing a liner and moving the crock up
I haven’t gotten a chimney pro yet. The nearest one is over an hour away☹️ Would you go with a liner even if the clay liner is in good shape? I appreciate all your feedback
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,460
central pa
I haven’t gotten a chimney pro yet. The nearest one is over an hour away☹️ Would you go with a liner even if the clay liner is in good shape? I appreciate all your feedback
Does the chimney itself have the required 1" clearance to combustibles?
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
Does the chimney itself have the required 1" clearance to combustibles?
If you mean a space between the house side of the chimney and the exterior wall of the house,….. maybe? There is a sheet of this fiber board? stuff on the exterior side of wall studs that is approx 1” thick. I’m not sure if the fiber board itself is combustible or not

image.jpg
 

IowaHuntr

New Member
May 22, 2022
22
Iowa
Have you had the chimney inspected by a chimney pro? If it were mine I would be installing a liner and moving the crock up
I understand that it would take a scope inside to see any fine cracks and check mortar between liner pieces but a visual inspection from below looks great🙃

44CF26ED-D7D7-4426-96D3-249F467DD5AA.jpeg
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,460
central pa
If you mean a space between the house side of the chimney and the exterior wall of the house,….. maybe? There is a sheet of this fiber board? stuff on the exterior side of wall studs that is approx 1” thick. I’m not sure if the fiber board itself is combustible or not

View attachment 295866
That is probably homisote or how ever you spell it and yes it's flammable.
 
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