Another clearance question.

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mushman

New Member
Mar 8, 2008
24
Long Island NY
I have a Jotul 3cb that was profesionally installed in 2003.When I was ready to purchase the dealed told me to get a brick wall up and he'd be ready to install the stove.
I removed the sheetrock put up some cement board then attached the bricks to that.
The dealer had told me that he'd be able to get the stove real close to the wall since the 3cb has a rear heat shield, and he did.It's around 7 inches off the wall.
I just redid my floors under the hearth pad so the stove is'nt connected to the stove pipe right now, so I figure now would be a good time to re adjust if needed.
The stove is top vented and goes straight out the top.
The wall gets warm,but not burning when we use the stove.I have a fan that blows the air behind the stove and into the hallway, and when that's on the wall is cool to the touch, but I would like to have the proper clearance for peice of mind.
So my question is, how close can a 3cb be placed in front of a brick wall attached to wood studs?.
If I need to move it up what sizes do the offset pipes come in?.
I wish I would have found this place back then so I could have researched this a little more.
On another note the dealer kept the top knock out,bar, and all, is this common practice?.If I ever wanted to rear vent the stove I guess I'll have to purchase the parts.I would imagine theese parts won't be to hard to get in the future, or should I just bite the bullet and buy them now.
 
I assume you just built a brick wall against the existing wall without a 1" breathable air gap behind it? From the sounds of it there is no air gap.

Look at page 12 of the manual

http://www.jotul.com/FileArchive/Te...ves/Jøtul F 3 CB/Manual_F3_USA_P06_240407.pdf

It talks about using wall protection and to refer to NFPA211. It then has some diagrams which ONLY how wall protection with a 1" air gap behind it. There is no where I can find where it says your wall protection MUST Have an air gap behind it. NFPA211 outlines wall protection methods with and without an air gap if I remember correctly. Basically the manual leaves me confused as to what table I should use when looking at your situation. My gut tells me that for the "Protected Surfaces" table Jotul is looking for a wall protected with a 1" air gap behind it as shown in the pictures on the page above. In this case you would use the unprotected surfaces table and measure from the closes combustible material to the back or corner of the stoves (depending on its orientation).

A Brick wall solid on thew wall behind it (without a 1" breathable air gap) still offers protection according to NFPA211 but only half the protection as if you build the wall with a 1" air gap.
 
Thanks, you're correct there is no air gap etween the studs and the brick, just cement board, and a lot of cement.I'm still confused.It seems that the clearance issues are with the pipe more than the stove.
 
Yes, you did not mention if you had single wall or double wall pipe, I forgot to ask that.

I also don't deal with Jotul stoves at all so I am not very familiar with their manuals. I just skimmed it looking for the clearance tables.
 
Im not familair with Jotul either, but from what I have seen you need to use rear wall protection and double wall pipe to get the smallest clearance off of the back of the stove. Single wall pipe has 18" clearances, double wall (close clearance) pipe has 6"
 
With single wall pipe your install sounds really suspect. I would go over that manual and take measurements. Let us know if you have any questions about specifics.

Might want to call a Jotul rep also and ask about the "Protected Surfaces" section of the table. Need to find out if the protected surface needs to have an air gap or if your brick wall is good enough.
 
If the beer hasn't warped my old mind too much tonight, NFPA211 would allow a reduction of clearance with the air gap but without it the clearance is from the stove or the pipe to the studs bricks or no bricks.
 
Beer must be working, BB - Brick alone allows a 33% reduction to the original combustible wall. The durock may add a tiny bit to that, but 1/3 is probably the figure to use.

So look up the stove rear clearance with whatever shield is on it, and then reduce by 1/3 to the original studs....that is, of course, general generic info.

Let me interpret the manual info shown....

Basically, it shows that you are more than OK with the rear stove clearance.

However, the single wall pipe must be 18" from the combustible wall ABOVE the brick - assuming brick does not go all the way up. If it does go up to the ceiling, I think you are OK as is.

If it does not, then use a pipe heat shield if the pipe is less than 18" - or replace interior pipe with double wall interior pipe.
 

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I knew it! That stuff is evil.

Never mind.
 
I installed my Jotul 3 cat. stove with the single wall stove pipe 8" from a wood mantel. It did make the manel hot, so I put a shield on the pipe. That did the trick. No matter how hot the pipe gets, the mantel stays just luke warm. I made a hearth of cement board (two layers each 1" thick I think) and ceramic tile, right on top of the plywood sub floor. If you have 1" cement board screwed right to the studs, and have stacked and mortared full size bricks in front of that, you should be OK if the pipe clearance is 7" and you put a shield on that. The brick is pourous and therfore provides dead air space in itself to some degree.

If on the other hand you used adhesive to bond those thin fake brick to the cement board you probably are too close with the stove itself. My stove has brick with an air gap at the stove level. I believe in safety, but I think you have probably got a better installation than half the stove installations I have seen. Some would scare you... and should
:exclaim:
 
Thanks all,the brick does go all the way up to ceiling(real bricks).I'm going to look into the shields, and the double wall pipe.I think I'd rather go with the shields for the extra heat.
Any other comments or suggestions?.
 
Ok Craig I gotta ask. I just looked at 211 and with bricks as a wall protector a 33% reduction is OK but minimum clearance is 24 inches with it as a wall protector. What am I missing here?
 
I am in the process of preparing for my new Jotul firelight. A friend told me I needed a 1" air vent in the wall, but when I went to order the cultured stone for the new wall, the rep told me the venting was unnecessary. If that is the case, I would rather build a partial wall and add a mantle at the top. Anyone have ideas, suggestions or pics? I am glad I found this site before starting the project, I have learned a lot so far. Thanks
 
A cultured stone wall is not the same as wall protection with a 1" air space behind it. Also, will the mantle be wood or stone? If wood there are clearance considerations too.

Best to start a new thread with a total description of your installation plans, location, flue type and current clearances. That way we can address specific questions and issues. If you can post a picture of the location, that would be great.
 
You could always put in a clearance reduction wall may not look the greatest. Mount 24 gauge sheet metal to the brick with 1in gap between the sheet metal and brick.
 
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