How tall and what chimney do I get?

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snow4me

Member
Nov 24, 2008
48
S/E Michigan
Well, with your help, I have decided to go with a Jotul F-100 for my hunt/snowmobile 12X20 bunkhouse. I appreciate all the feedback I have gotten in my original thread and decided maybe I should start a new one for my new questions.

The stove is going to be located in the corner of the the 12X20 floor (the room is all open, one big room). The house has a 12/12 pitch roof so it is very high. If the pipe comes straight out of the top of the stove, does it need to be higher than the highest point of the roof, about 15ft to the peak? How much above that? Also, what brand and kind of chimney should I get? I have usually bought the best I can afford when I buy important stuff like this so while I won't say money is no object, I want the best as far as safety for my family goes. Thanks for the great forum!!!

Daryl
 
It needs to extend up a minimum of 3 feet above the point at which it penetrates the roof. Then it must further extend up, if necessary, until it's at least 2 feet higher than any part of the structure within 10 feet horizontally from it. Given the small footprint of your structure, I won't be surprised that you find you have to run it up 2 feet higher than the peak of the roof. That may well mean it's going to need to be braced. If it's in a heavy snow area, you'll probably want to install a cricket, as well, to protect the chimney from the weight of snow sliding down the roof. Everything from the ceiling support box up to daylight must be Class A chimney. Brand doesn't really matter, they're all tested to the same standard. From the stove to the ceiling support box you can use either single or double wall connector pipe, but I expect you'll be going with double wall to get the clearances as tight as allowable. Rick
 
The flue must terminate at least 3 feet above the roof and at least 2 feet above any portion of the roof within 10 feet.
It also must be located away from trees or other structures. Plan on using double-wall interior connector pipe like Simpson DVL or equivalent to connect the stove to the high temp pipe at the ceiling.

PS: Looks like Rick and I fired off at the same time. Here's a graphic of the 10 3 2 rule.

If the exterior high temp (class A) pipe is taller than 5ft it will need to be braced once every 5 feet.
 

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snow4me said:
Well, with your help, I have decided to go with a Jotul F-100 for my hunt/snowmobile 12X20 bunkhouse. I appreciate all the feedback I have gotten in my original thread and decided maybe I should start a new one for my new questions.

The stove is going to be located in the corner of the the 12X20 floor (the room is all open, one big room). The house has a 12/12 pitch roof so it is very high. If the pipe comes straight out of the top of the stove, does it need to be higher than the highest point of the roof, about 15ft to the peak? How much above that? Also, what brand and kind of chimney should I get? I have usually bought the best I can afford when I buy important stuff like this so while I won't say money is no object, I want the best as far as safety for my family goes. Thanks for the great forum!!!

Daryl

Fossil and BeGreen are correct. You may want to relocate the chimney closer to the ridge. That way the bracing issue will go away. The total height wil probably be the same but you will use less expensive chimney. It would be easier to clean if it is 2 ft above and close to the ridge. Just a thought.

RPK1
 
Also, locating it closer to the ridge, more of the chimney will be in warm space giving better draft and less potential for creosote buildup. If you cannot locate the stove more central, maybe you can offset the stovepipe with a pair of 30 degree elbows. Try not to exceed 30 degrees as the more horizontal you go the more creosote can build up.
 
Adding to LLigetfa's comments about the advantage of keeping as much of it in the house as you can, if you punch it out about a foot from the ridge, all you'll need is about 3 feet of exposed chimney, no cricket, no bracing. Both simpler and less expensive. Advantages inside and out. Rick
 
fossil said:
Both simpler and less expensive.
and better looking IMHO. Beats having what looks like an ICBM sticking 12 feet in the air.

As a secondary, more heat in the house reclaimed from the inside pipe. My former home had a 12/12 roof with the SS chimney near the ridge. I ran the chimney through a chase all the way down to the first floor so there wasn't any cost saving. By venting the chase, I recovered enough heat to warm the second floor.

A great room with open cathedral ceiling need not be chased in and need not be SS chimney down to the stove.
 
Pricewise, the best deal I found was Lowes. Class A chimney - $67/3ft, $47/2ft. stove pipe (single wall) was $8/2ft. Chimney locking bands - $5ea. Ceiling support kit - $130 - had everything else for flat sheetrock ceiling/then attic.

Lowes had lots of chimney/stove parts. HomeDepot had none. Kinda strange - they usually are mirror images of each other.
 
I am really kind of stuck with having it in the corner, gonna look like a periscope! Is there any advantage to running it out the back and up the outside wall? Does it still need to be that high above the roof?

Thanks, Daryl
 
If you offset the pipe with a pair of elbows, it shouldn't look like a periscope. Just work out the angles and the lenghts so you have as much vertical straight up from the stove before the first elbow and it should look OK.

I really discourage anyone from going through a wall and up the exterior. You don't save anything on height and just end up with a lot of cold chimney and lousy draft. It will most likely creosote bad and collect in the Tee where a chimney fire is likely to start. My father made that mistake and ended up staring at a smoldering hole in the ground. Lost everything but the shirt on his back. Got screwed over by insurance too.
 
snow4me said:
...Is there any advantage to running it out the back and up the outside wall?

No. There are, in fact, a couple of disadvantages to doing it that way. More directional changes, and more chimney exposed to outside, more difficult to clean, more opportunity for creosote formation, poorer draft, more complicated/costly installation. OK, more than a couple. Rick
 
So, I could go straight up then angle it with an elbow where the vertical meets the ceiling and run it up toward the peak along the ceiling and elbow it again out the top? If so, I like it! I want a flat black pipe inside also.

Thanks again, Daryl
 
Zackly. Rick

EDIT: I recommend double wall pipe, and welded (not corrugated) elbows...for clearances and cleaning.
 
snow4me said:
So, I could go straight up then angle it with an elbow where the vertical meets the ceiling and run it up toward the peak along the ceiling and elbow it again out the top? If so, I like it! I want a flat black pipe inside also.
You got it, except the angle of the elbows might be a little less than the angle of the ceiling. Kind of converging lines look.

A 12/12 roof is 45 degrees. At one time you could buy 45 degree elbows and I used 45's on my former home. Current wisdom says don't exceed 30 degree elbows so 30 from 90 is 60 degrees on the pipe. My current home uses 30's. This ensures any creosote that curls, peels, and falls down the pipe go back into the stove if it isn't rear exhaust.
 
45's are easily obtained for connector pipe. It's chimney pipe that the most acute elbows most commonly available are 30's. Rick
 
fossil said:
45's are easily obtained for connector pipe.
Yes, I realize that. I was using the current thinking of chimneys to drive home the point that both chimney and connector pipe have the same laws of physics WRT the angle of repose of creosote.
 
I never argue with the laws of physics. I'd use 30's in my connector pipe rather than 45's, but can't seem to find them. Seems to me it would make cleaning easier, too. Still lookin'. Rick
 
Daryl
I have a similar installation and weekend cabin. The house was built with the wood stove being our weekend heat. The stove is at the end of the house, 45 degrees in the corner. The house is 28' wide x 3 long with 12/12 pitch cathedral ceiling, open bedroom loft. The single wall flat black pipe goes out of the stove, straight up about 10' inside into the 1 foot square box in the ceiling that connects the single wall to the double wall. The double wall stands about 10' above the roof with a support brace.

I knew the chimney was going to be high and hard to get to the top for cleaning. So I built a 5/12 pitch side porch roof that intersects with the main 12/12 roof above where the chimney comes through. This gives me a 6' x 20' covered side porch from temporary wood storage and a easy roof to walk on.

I don't think I'd do the bends around the ceiling to the peek. Bends collect the bad stuff, restrict the draft, and have you checked this idea with your wife, it may not look so good. A friend has 3 bends, it's hard to get the draft going and he needs to take it apart twice a year for cleaning. My straight pipe drafts very well, and is easy for me to clean from the top down. Although the chimney cleaners do clean from the bottom up with a flex rods and a vac.

Good luck with the place. I can hear the kids now, they will love it.

Tom
 
fossil said:
I never argue with the laws of physics.

Don't argue with physics and don't try to molest a tree with ill suited instruments.

I had my Issac Newton moment the other day with a pecan tree.

I was putting out round bales with the tractor and front end loader when I seen that the latest freeze finally loosened the pecans in one of my favorite trees. Oh yes, the ever elusive and very tasty Shawnee II Pecan that produces a single crop only every 4 or 5 years was ready for the picking. All I needed to do was shake the tree.

As expected, I put the tractor and loader to good use here and the pecans fell like hail. Then came the 3 inch limb which promptly bounced off the tractor hood and nearly KO'd me. I was not hit but it did get my attention.

Lesson learned but these pecans are worth it! :)
 
Thank you all for your replies!!! Looks like I have a lot to still think about. I have drawn my cabin up on CAD at work "during lunch" and am going to place the stove in there tomorrow/today. It will be going in the corner on an angle. If I do use (2) 30 degree bends, can they anywhere I want them to be? I mean, does the 60 degree pipe that goes between the two connectors have to be under a certain length? Heck, the place is only 12ft wide, how long could it be! LOL Couple more things... Do I use single wall inside and double wall outside? How far away from the peak should my pipe be, horizontally?
I would like the 30 degree pipe at the exit point of the house to connect directly to the adapter thingy that goes through the roof, whats that called? Basically, I just want to see the vertical going up from the stove to the first 30 degree elbow and then the 60 degree pipe to the second 30 degree elbow and nothing else inside. Sorry to be confusing, it's the only way I know how to explain it.

Thanks!!!!!
Daryl
 
The ICC black pipe I spec'd is double wall and allows as little as 6 inches clearance even on the 60 degree pipe following the ceiling. You can't do that with single wall. The cathedral adapter will pretty much dictate the clearance to the ceiling anyway, which will be more than the 6 inch minimum.

The SS chimney would start just below the ceiling with a cathedral adapter. About 2 feet off the peak and 2 feet above the peak would put 4 feet of pipe outside plus what the cathedral adapter needs, so around 7 feet total would be my guess without looking at the design drawings.

You would want to put the top 30 degree elbow right to the cathedral adapter and start your 60 degree slope down until you are directly above the stove, transitioning back to vertical again with the second elbow. The rise/fall you get for the run will determine the lengths. ICC has an offset table to help. Draw it up in CAD and you can work out the lengths. That was how I did it when I designed and built my house.

Good luck
 
snow4me said:
Heck, the place is only 12ft wide...
Hmmm... Sorry, I missed that little detail earlier. So then only 6 feet from ridge line to outer wall? Assuming an 8 foot wall, 14 feet to the ridge? If you did just go straight up, you only have 8 feet outside to get 2 feet above the ridge. I was picturing 12 feet of pipe outside assuming the ridge was 10 feet away.
 
Daryl,
With the small size of this...... The stove and pipe may need almost 18" clearance from each of the side walls. I think your going to have a lot turns and very short runs to send this out near the ridge. Take a look at BeGreen's diagram, if you go out near the ridge you need to have a minimum pipe outside, about 3'. Straight up from the stove you should end up lower, 2' over the top of the ridge.

When I clean mine from the top down, I take off the top 3' section with the cap.

To keep the stove as tight to the corner I used Jotul's rear heat shield and heat shields for the stove pipe. If they make them for your stove you may be able to keep it tighter to the corner.

Here's the link for the instalation information.
http://www.jo.us/FileArchive/Technical Documentation/Wood Stoves/Jøtul F 100 Nordic QT/Manual_F_100_USA_P03_090608.pdf

Tom
 
xman23 said:
Daryl,
With the small size of this...... The stove and pipe may need almost 18" clearance from each of the side walls. I think your going to have a lot turns and very short runs to send this out near the ridge. Take a look at BeGreen's diagram, if you go out near the ridge you need to have a minimum pipe outside, about 3'. Straight up from the stove you should end up lower, 2' over the top of the ridge.

When I clean mine from the top down, I take off the top 3' section with the cap.

To keep the stove as tight to the corner I used Jotul's rear heat shield and heat shields for the stove pipe. If they make them for your stove you may be able to keep it tighter to the corner.

Here's the link for the instalation information.
http://www.jo.us/FileArchive/Technical Documentation/Wood Stoves/Jøtul F 100 Nordic QT/Manual_F_100_USA_P03_090608.pdf

Tom

According to the jotul manual I have, when the stove is placed in a corner on an angle, I need 10 inches to a combustable wall or 7 inches from a non-combustable wall. I need 10" since it is going to be knotty pine. This is right off of the F-100 installation instructions. Correct me please if I am wrong.

Daryl
 
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