stove pipe to chimney pipe transition clearance

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Stephany

New Member
Hearth Supporter
Jun 12, 2007
17
Hi -

We are still trying to get a wood stove into our 3 story A-frame. Originally, we were trying to follow the 23 degree slant of the side wall with the pipe, but due to a variety of complications, we have shifted the stove location so that the pipe can go straight up through the 3 story cabin. So now I am down to 2 questions:

1 - Since the stove is now out of the corner and more in a main walkway, we are trying to minimize the distance between the wall and the back of the stove as much as possible. With single wall pipe and a pipe shield, the Lopi Leyden requires 11" of clearance between the pipe and wall. But once we transition to the Class A chimney pipe (at the ceiling), it only has to be 2" fom the wall. How and where do we move the single wall pipe 9" over to the Class A pipe? Can we use elbows in the single wall to move 9" over to the Class A before we connect to the Class A - or do we have to use elbows in the class A to move from 11" to 2" in the living space above on the 2nd floor (surrounded by a chase)?

2 - Is it okay for us to install the pipe ourselves? We are very handy with a lot of home remodeling experince, but this is our first chimney. The installers are quoting $1200+ (not including the cost of the pipe) to install, and frankly it just doesn't look that difficult now that it is a vertical install!

Thanks for your help with this,

Stephany
 
Iam not sure i follow you but it sounds like you want to know how to reduces the clearences all the way down to 2 inchs your pipe with pipe sheild must maintain the 11 inches regadrless of what the class A chimney clearence is .
 
Why not use doublewall to reduce clearances?

Also, from what I understand you have to connect the lower pipe to the ceiling support at whatever clearance it requires, then you can use elbows in the class A section to move closer.

There is nothing "illegal" about installing your own fireplace venting. Peace of mind is what you get when a pro does it.
 
"Peace of mind is what you get when a pro does it."

Really? I would disagree, there are good ones and bad ones but assuming they are good is not wise. I just called back my installer to reinstall the class A that was put less than 2" from my wooden rafters. It's been a long time since you could assume that pride in professional craftsmanship was the norm.
 
That is very true... well if you live around the store I work at and come to it, then my statement holds true. I do random quality inspections of all the guys work and it is usually top notch. They will refuse to install a unit if it means violating code or the install manual, even though this means they wont get paid for doing the install.
 
Thanks all for the replies so far.

JTP - I would love to use doublewall stove pipe, but the Lopi Leyden requires 14" clearance between the doublewall pipe and wall, instead of just 11" with the singlewall + pipe shield.

Can I connect to the class A chimney pipe before I go through the ceiling....say, right at the stove? Then I could use Class A elbows to move the pipe from 11" to 2" before the pipe goes through the ceiling? Then my pipe and chase on the 2nd floor would be straight up at 2" from the wall.

Please let me know if you are totally confused!

Stephany
 
Is the stove close to the ceiling? why not make it a straight up the stove cant be moved any closer i dont get the chimney issue the stove will still be at 11 inches so why do you need to shift the chimney?
 
Hi Stoveguy,

The chimney passes through the ceiling on the 1st floor and runs through a bedroom on the 2nd floor, then passes through that ceiling to a 3rd floor and exits the A-frame roof there. Since at 11" from the wall, the pipe is in a walkway at the end of the bed (on the 2nd floor), I would like the pipe to be as close to the wall as possible, preferably at 2". Plus, since I have to build a chase around the pipe on the 2nd floor, I would rather it not be a column in the middle of the floor. Does that help clarify my motive?

Thanks for your question -

Stephany
 
I don't see anything wrong with bringing the class A down into the 1st floor and offsetting there, you could build a box around it and then use a finishing collar to transition to the single wall pipe. In this situation you would not have a ceiling support box and thus nothing holding the wieght of the pipe. What I would do to overcome this is use at least one set of roof support brackets. You could put one on the floor of the second floor where it penetrates and possibly one up higher.

Anyone else see anything wrong with that?
 
I think you are not getting thr correct code compliant advice. A double wall pipe has 6' clearance. A pipe shield is according to manufacture's specs of the shied

once the class A is entered to has to be the rest of the way, Class A pipe has to be enclosed within a NFPA 211 enclosure within the living space ,
Meaning a one hour protection chase . Plain class A can not pass threw living space there are two ways to interpete code the manufacturer's specs 6" for double wall connector pipe
most connector pipe has a length limite usually less than. 10. connector pipe can not use passing threw floors'
 
I thought 14" sounded a little too much for double wall.... but he stated it was something particular to the stove so I wasn't going to argue.

Elk, about what I suggested? If you did build this 1 hour burn chase around the entire class A system, is what I said legit? Or would the Class A have to end at the first floor ceiling?
 
Once class A is entered one can not switch back to connector pipe then back to class A threw the next ceiling or wall penatration

Another way to put it is once the chemney is started it has to continue Connector pipe can not comprise the chimney

If it enters in an attic or non living space it does not need to be enclosed in a chase

Again one can use the stove for specs or use the pipe manufactures specs. to me pipe shields do serve a purpose but ugly
myh oppinion I would much rather see a double wall pipe

Code is 18" single wall clearance from combustiables concerning wood stoves, all other reductions are designed manufactures specs on the pipe used
 
Hi Elk,

The clearances I had noted were stated by Lopi in the Leyden brochure. Are you saying that I can use the pipe specs instead and completely ignore the clearances for the wall to the back of stove? Why are Lopi's specs so different?"

Or - do I need to keep the back of the stove 11-14" from the wall, then I can use an elbow in the doublewall pipe to move it over to 6". then connect to the class A in the ceiling at 6" from the wall?

Thanks very much for your answers and the clarification,

Stephany
 
There are two set of clearances that have to be met the stove placement and the pipe requirements

If the manufacturer says the stove can be set 12" from the wall that where it should be set, mind you there is no penalty for placing it a little further away..

just added safety. In order to set it this close plain single wall pipe can not be used if is is less than 18" to combustiables. One could use a heat shield or

use double wall pipe, that only requires 6" clearance or what the manufactures states.

Me, I would run straight up, again no penalty for having more distance. It also will draft better, have a cleaner appearance and double wall elbows are not cheap
 
Elk, in no way was I suggesting to switch back and forth between class A and connector pipe... I think you misunderstood what I was suggesting.
 
This seams simple to me.... Run double wall up to say 2-3' of the 1st floor ceiling then use 2 class A 45s to offset the remainder of the chiminy to allow for 2" clearance and put a chase around the rest with a duroc lining. Done deal and minimul space lost on the 2nd & 3rd floors.
 
nshif said:
This seams simple to me.... Run double wall up to say 2-3' of the 1st floor ceiling then use 2 class A 45s to offset the remainder of the chiminy to allow for 2" clearance and put a chase around the rest with a duroc lining. Done deal and minimul space lost on the 2nd & 3rd floors.

Thats pretty much what I was suggesting.
 
Brier Steph said:
Hi Stoveguy,

The chimney passes through the ceiling on the 1st floor and runs through a bedroom on the 2nd floor, then passes through that ceiling to a 3rd floor and exits the A-frame roof there. Since at 11" from the wall, the pipe is in a walkway at the end of the bed (on the 2nd floor), I would like the pipe to be as close to the wall as possible, preferably at 2". Plus, since I have to build a chase around the pipe on the 2nd floor, I would rather it not be a column in the middle of the floor. Does that help clarify my motive?

Thanks for your question -

Stephany
The chimney needs to continue as class A from the first floor up so where go threw the ceiling the clearances can stay 2 inches from that point so i guess the real question is can you locate the stove in a spot on the first floor that you can mantain your 11 inch cleareance and place the chimney up stairs it will be alot easier to make the off sets you need with the stove pipe then with the class A chimney.
 
Once you go through the ceiling attach a 30º Angle to the ceiling support and then a straight length to get you toward the wall (depending on manufacturer), then attach another 30º Angle to get you back straight 1.5" or 2" from the wall (amount of straight length and clearance to combustibles will vary by manufacturer, i.e. Metal-Fab has 1.5" CTC, others are 2").
 
Sounds to me like the bend wants to be in the living room, BEFORE going through the ceiling, as the desire is to be at the 2" clearance point when coming through the floor into the 2nd story.

Given that, unless there is a clearance issue with the ceiling box, I'd run the Class A straight down at the 2" clearance to the ceiling box, then a couple of 45's or even 30's to jog down and out enough to get the clearance to the double wall going straight down to the stove....

Gooserider
 
Hi Gooserider,

You are exactly right - I would prefer that all the bends happen in the pipe on the first floor before it goes through the ceiling. JTP also suggested running the class A down through the ceiling, but I have 2 questions about that approach:

1- would I really have to build a chase around the part of the class A that hangs down from the 1st floor ceiling - including around the elbow? Is there a "connector elbow" that joins to doublewall at one end and class A at the other?

2 - how would I support the class A pipe that is hanging down in the 1st floor? Is it enough to use a wall support on the 2nd floor (and a roof support outside) or does the pipe need to be supported from below? The length of the class A chimney will be about 20' + the stove pipe.

Oops - I guess that was really 4 new questions!

Thanks very much for all your suggestions everyone! I really appreciate the help noodling this!

Stephany
 
stef an extra length of clas A above the stove would not need a chase.

it also would be supported by the ceiling box and the pipe exiting the stove
 
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