Stove pipe vertical to horizontal ratio?

[IowaHuntr]

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!

 

[DAKSY]

That information is dependent on each individual stove. What unit are you installing & what does the manual indicate?

 

[IowaHuntr]

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]

The most important thing is overall chimney height and size

 

[bholler]

What is your current chimney height size condition etc?

 

[IowaHuntr]

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]

What is your current chimney height size condition etc?

 

[IowaHuntr]

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.

 

[bholler]

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]

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]

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]

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

 

[IowaHuntr]

Does the chimney itself have the required 1" clearance to combustibles?

There is a 1” space between brick and stud where there is no fiber board in between

 

[IowaHuntr]

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🙃

 

[bholler]

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.

 

[IowaHuntr]

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

I can probably replace that with cement board during renovation

 

[bholler]

I can probably replace that with cement board during renovation

Or just put in an insulated liner and it's not an issue