[NEWBIE] Chimney pipe

[gattu marrudu]

Hi, I am completely new to the wood stove world. I just bought a Jotul 4, barely used from what I can see. The stove came with a back flue adapter and built-in damper, no other chimney parts. So I could use some installation advice if somebody would be so kind.

The stove will sit in the kitchen pretty close to the exterior wall, which is brick lined with plaster and lath on the inside. Outside the exterior wall is an unheated closed porch with a plywood and tar roof. For the floor, I would build a platform with clay tiles or bricks, or maybe just some colored concrete (until I figure out my final design for the kitchen). For the back wall I could also use bricks, or

Then, I need to figure out the exhaust part. My idea is to open the wall at the stove height and shoot the chimney straight out, then go up 90 degrees and through the porch roof. I want to use the back outlet of the stove because I plan to use the top of the stove for cooking.

I read that in order to go through a combustible wall (plaster/lath) I need a thimble, which is very expensive (I see in the 300-400$ range). Would this be just to protect the plaster and lath? In that case, since the plaster wall is not bearing, could I just cut out a section up to a safe margin, and replace it with ceramic fiber board or another noncombustible material, and just go through the brick with a double walled pipe?

Also, what would I need to go through the porch roof? The pitch is quite low, and all the roof adapters seem to have a much steeper pitch.

Thanks in advance.

gm

 

[begreen]

This is a very radiant stove with high clearance requirements of 38" to the rear wall. The lath in the wall is combustible. Adding insulation on top of the wall is not sufficient for clearance reduction. To reduce clearances (to 12") a proper NFPA 211 wall shielding is required. Also, stove pipe can not penetrate a wall the thimble and through-the-wall pipe must be class A chimney pipe with a class A thimble.

 

[gattu marrudu]

Thanks for the tip about the heat shield.

I see there is no way around the thimble, I'll take that into account. Will I need something similar to pass through the wood / tar roof? Or are there specific parts for that?

 

[gattu marrudu]

Another question: since the unheated porch can get pretty cold in the winter, would you suggest using double-walled pipe so that the chimney doesn't cool too quickly and slow down the draft? I don't mind the extra heat going into the porch, actually that would be good.

 

[begreen]

Another question: since the unheated porch can get pretty cold in the winter, would you suggest using double-walled pipe so that the chimney doesn't cool too quickly and slow down the draft? I don't mind the extra heat going into the porch, actually that would be good.

Be careful with descriptions for the flue system piping. There is double-walled stove pipe and there is double-walled chimney pipe (class A high temperature). They are very different in construction and the locations where they are used. Stove pipe can not pass through a wall. This means that every thing on the porch side including the roof penetration, the tee, and the horizontal leg going through the wall must be chimney pipe and the thimble must be one for the chimney pipe.

There are some red flags appearing with the plan that need to be considered. Adding 2 right angle turns to the smoke path will slow down the draft. The horizontal run will make this worse. If then, the chimney above the roof is not tall, the system may draft poorly and stove performance may be impacted. For this reason, a straight up, thru the roof chimney is advised. This is can also be much less expensive due to less parts involved. If cooking on the top is important, then consider coming out of the back with an elbow and then going straight up with double wall stove pipe to the ceiling, then class A chimney pipe through the roof. Double wall stove pipe has a clearance requirement of 6" to combustibles.

 

[gattu marrudu]

Be careful with descriptions for the flue system piping. There is double-walled stove pipe and there is double-walled chimney pipe (class A high temperature). They are very different in construction and the locations where they are used.

Oh, that's a good thing to know. Thanks for the distinction.

Stove pipe can not pass through a wall. This means that every thing on the porch side including the roof penetration, the tee, and the horizontal leg going through the wall must be chimney pipe and the thimble must be one for the chimney pipe.

My plan in the first post's attachment only has one 90 degree turn: the exhaust goes out the back of the pipe, through the brick wall (using a thimble, as you suggest), then straight up and through the roof. There is no tee.

So I'll have to use class A chimney pipe all the way from the thimble to the roof? What about the connection between the stove and the thimble?

There are some red flags appearing with the plan that need to be considered. Adding 2 right angle turns to the smoke path will slow down the draft. The horizontal run will make this worse. If then, the chimney above the roof is not tall, the system may draft poorly and stove performance may be impacted. For this reason, a straight up, thru the roof chimney is advised. This is can also be much less expensive due to less parts involved. If cooking on the top is important, then consider coming out of the back with an elbow and then going straight up with double wall stove pipe to the ceiling, then class A chimney pipe through the roof. Double wall stove pipe has a clearance requirement of 6" to combustibles.

I can't easily go straight up inside the kitchen because it's a two-floor house. My only option is out the porch. Or maybe reusing an old chimney in another part of the kitchen, but that would take at least 3 elbows and a lot of horizontal run.

If I go out the porch, must the chimney go up all the way above the second floor to get enough draft? Or is there just a minimum clearance above the porch roof?

 

[begreen]

My plan in the first post's attachment only has one 90 degree turn: the exhaust goes out the back of the pipe, through the brick wall (using a thimble, as you suggest), then straight up and through the roof. There is no tee.

It has to have a tee, there are no 90º elbows in chimney pipe.

I can't easily go straight up inside the kitchen because it's a two-floor house. My only option is out the porch. Or maybe reusing an old chimney in another part of the kitchen, but that would take at least 3 elbows and a lot of horizontal run.

Can be done either by enclosing the pipe on the next floor or locating in a good area. For example, our chimney pipe goes up through a closet corner on the second floor.

If I go out the porch, must the chimney go up all the way above the second floor to get enough draft? Or is there just a minimum clearance above the porch roof?

The chimney pipe must obey the 3-2-1 rule for roof clearance.

 

[gattu marrudu]

OK, it looks like I may have to rethink this whole project. I do have an unused fireplace that I could expand in height to fit the Jotul, or just get rid of the Jotul and get a fireplace insert. In that case I could reuse the existing chimney and brick enclosure, I'd just have to get a chimney liner I guess. No cooking option, but it looks like my kitchen just won't accommodate a stove. Thanks for all the info.

 

[begreen]

Show us what you've got for more brainstorming.

 

[gattu marrudu]

Here's a picture of the kitchen with the Jotul where I wanted it. There is a chimney above the sink. If I had to move the stove to have a decent path for the flue pipe it looks like I'd have to tear down most of the kitchen, reroute plumbing, and lose the overhead cabinetry and counter space.

The other pic is the living room fireplace (that I was just starting to repaint today) , obviously too low for the Jotul but it has an unlined chimney. At that point, it would be easier to resell the Jotul and buy a smaller stove that fits in the existing space than demolishing the fireplace.

 

[begreen]

An insert in the fireplace may be a simpler option. If the Jotul is in excellent condition it could bring a decent return of $800-1000 to the right person. It's a strong heater. Average condition price is $400-600.