Conflicting information for clearances

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katiek

Member
Jan 31, 2019
19
Maine
Hi,

I need help understanding the clearances for this diagram. It is for the Jotul Firestove 3 Woodstove.

[Hearth.com] Conflicting information for clearances

It is currently installed upon an Imperial stove board that is not big enough. That stove board is resting upon a wood floor. The wall behind the stove is also not properly protected. We just moved into the house and someone from the insurance company came and took a look inside and said the wood stove has to go. I had the fire department come take a look and they said that it should be okay if the hearth size and wall protection is properly installed.
I am trying to get away with the smallest, least intrusive, affordable option for it to be up to code. It's a small room and a small house.
According to the diagram it is configured as T4. The stoves dimensions are 13deep, 22wide, 20tall (not including the 8inch legs). What do the side clearances need to be on the non combustible sides? I am most likely going to purchase another Imperial stove board for the floor but want to be sure on the dimensions required before doing so.
Help!
 
The hearth pad needs to be at least 36" wide. Normally the length goes from 16" in front of the stove door to the rear wall. Imperial stove board may not have the proper insulation value that's required. According to Imperial, the R-Value = 0. For use with appliances that require only ember protection. This product is not to be used with appliances that specify Type 2 thermal floor protection or a specific R-value requirement.

You may want to use 4" brick instead or cement blocks with a metal sheet. Does the stove have the standard (8"?) legs?

Can you clarify the side clearance question? Clearances are to combustibles. Is there a side wall near by? Can you post a picture of the installation location?
 
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[Hearth.com] Conflicting information for clearances

So if the floor protection is 36" wide than that means that it gives me about 7" side clearance under the stove. Can I follow that since it is what is listed in the manual?
I believe the National Fire Protection Association says it needs to be 18" on all sides. If I am calculating this correctly (taking stove size, and clearance to wall being 12") that would mean a hearth pad that is 58" wide by 62" deep. That seems enormous to me!
 
View attachment 239758

So if the floor protection is 36" wide than that means that it gives me about 7" side clearance under the stove. Can I follow that since it is what is listed in the manual?
I believe the National Fire Protection Association says it needs to be 18" on all sides. If I am calculating this correctly (taking stove size, and clearance to wall being 12") that would mean a hearth pad that is 58" wide by 62" deep. That seems enormous to me!
It is a listed appliance so you go by the clearances stated in the manual not the generic ones for unlisted stoves given by nfpa211
 
Thanks for posting the picture. It looks like side clearances to combustibles like a wall are not an issue. The depth of the hearth pad and rear clearance for the stove to the wall behind it are critical. The metal shield behind the stove can reduce the rear clearance to 13" if the stove is connected with double-wall stove pipe. However, the metal wall shield should be elevated from the floor by an inch so that air can freely convect underneath it. If that is done then the hearth protector can be 50" x 36". It will need to be an alternative to Imperial's type 1 stove board.

What are the white panels behind the stove?
 
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Okay. I really want to understand this whole process and how to read the manual with regard to clearances but just can't wrap my head around it. Do you know if it's standard practice for a stove installation shop to come look and help get an existing stove installed properly?
 
That varies from shop to shop and depends on the installer. There are good and not so good in the industry. You are close to being proper, but there are some details that need addressing. Before contacting a shop, have the specifics needed so that you can tell when someone is giving proper info vs blowing smoke. Go ahead and ask questions. bholler and HomePA are professional sweeps. Webby3650 is a professional installer. You will get uncolored advice here, no one is making any money on helping.

Is the stove pipe single or double-wall?
 
Thanks for posting the picture. It looks like side clearances to combustibles like a wall are not an issue. The depth of the hearth pad and rear clearance for the stove to the wall behind it are critical. The metal shield behind the stove can reduce the rear clearance to 13" if the stove is connected with double-wall stove pipe. However, the metal wall shield should be elevated from the floor by an inch so that air can freely convect underneath it. If that is done then the hearth protector can be 50" x 36". It will need to be an alternative to Imperial's type 1 stove board.

What are the white panels behind the stove?

The white panel behind the stove was already here. It is painted sheet metal. How are you calculating the 50"? Thank you so much for all of the input!
 
When the fire department came by they said the stove pipe (which passes through a combustible wall o_O) is installed into a insulted thimble. I think the pipe is single but passes through the insulated thimble in the wall. Does that make sense?
 
How are you calculating the 50"?
36" ( dimension B) + 13" (allowed reduced clearance with double-wall pipe and rear shielding).
 
When the fire department came by they said the stove pipe (which passes through a combustible wall o_O) is installed into a insulted thimble. I think the pipe is single but passes through the insulated thimble in the wall. Does that make sense?
Yes, but if the pipe is single-wall then that increases the rear clearance. Single wall pipe needs to be 18" from the wall.
 
Yes, but if the pipe is single-wall then that increases the rear clearance. Single wall pipe needs to be 18" from the wall.
does rear shielding mean the heat shield listed? the stove does not have the heat shield...it's a retired model and in my brief search I couldn't find the part.
 
Thats good. I would center the stove on that wall if you can it would get rid of an elbows. If you are ordering or building a new hearth make it bigger so if you get a new stove down the line you dont have to redo again. Is this for supplemental heat.
 
Thats good. I would center the stove on that wall if you can it would get rid of an elbows. If you are ordering or building a new hearth make it bigger so if you get a new stove down the line you dont have to redo again. Is this for supplemental heat.

It is for supplemental heat. It's in a really small room in our really small house! If we were to move the stove in an effort to get rid of the elbow it would block the doorway (hard to tell from the pic).
 
The manual is on the Jotul US website here:
(broken link removed to https://jotul.com/us/guides/identify-your-old-j%C3%B8tul-product-and-user-manuals)
(broken link removed to https://jotul.com/us/guides/_attachment/12842?_download=true&_ts=13e1dadc5f7)
does rear shielding mean the heat shield listed? the stove does not have the heat shield...it's a retired model and in my brief search I couldn't find the part.
Yes, that is the tested clearance. Unfortunately the only place you are likely to find the part now would be scavenged off of an old stove. Does the stove have the bottom heat shield on it?

Is the white painted metal behind the stove on 1" spacers and open at the top and bottom? If so, someone already put up an NFPA wall shield. That should suffice for the stove rear clearance, but doesn't change the single-wall stove pipe requirement of 18".
 
The manual is on the Jotul US website here:
(broken link removed to https://jotul.com/us/guides/identify-your-old-j%C3%B8tul-product-and-user-manuals)
(broken link removed to https://jotul.com/us/guides/_attachment/12842?_download=true&_ts=13e1dadc5f7)

Yes, that is the tested clearance. Unfortunately the only place you are likely to find the part now would be scavenged off of an old stove. Does the stove have the bottom heat shield on it?

Is the white painted metal behind the stove on 1" spacers and open at the top and bottom? If so, someone already put up an NFPA wall shield. That should suffice for the stove rear clearance, but doesn't change the single-wall stove pipe requirement of 18".
I thought that would be the case regarding the heat shield. I am really struggling with what the right move here is! Why would the stove pipe need to still be 18" from the wall but not the stove itself if the sheet metal with spacers are used. The stove pipe doesn't get nearly as hot as the stove itself.
 
The stove pipe has the potential to radiate a lot of heat. Over time this radiated heat can cause pyrolysis which is a lower of the ignition temperature of a combustible. The 18" requirement is to provide an adequate margin of safety for the wall, ceiling or wood work near the pipe. Double-wall stove pipe has a 6" clearance requirement. That is why the manual allowed for a closer stove rear clearance with a rear stove shield and double-wall stove pipe.

The single-wall pipe can be shielded or the wall shielding extended to cover for this.

Is the white painted metal behind the stove on 1" spacers and open at the top and bottom?
 
The stove pipe has the potential to radiate a lot of heat. Over time this radiated heat can cause pyrolysis which is a lower of the ignition temperature of a combustible. The 18" requirement is to provide an adequate margin of safety for the wall, ceiling or wood work near the pipe. Double-wall stove pipe has a 6" clearance requirement. That is why the manual allowed for a closer stove rear clearance with a rear stove shield and double-wall stove pipe.

The single-wall pipe can be shielded or the wall shielding extended to cover for this.

Is the white painted metal behind the stove on 1" spacers and open at the top and bottom?

The white metal is not on spacers and it is resting on the floor. Due to the paint, the fire department said it should be replaced. I think we would extend the sheet metal to cover the wall behind the stove pipe.
 
Imperial makes a type 2 stove board that is R-1.5
It is in my avatar. My stove required R-0.13 so it was more than adequate in my case.
 
Too bad, the white paint would be ok if it was high temp paint. But you would have to know that.

This article may be helpful if you are going to replace the wall shield with a proper one.
https://www.hearth.com/talk/threads/wood-stove-wall-clearances-primer.147785/#post-1987380

What prompted the fire dept. visit? Did they give you a written report?
The fire department came by at my request after I got a message from the insurance company that the stove had to go. They didn't give a written report at the time...in hindsight I should have asked. The person that came left me with a checklist of things that need to be done which mostly came down to increasing the floor protection and increasing the wall protection. The person that came from the fire station did say that the floor protection needed to extend 18" on all sides of the stove. However, the Jotul manual floor protection size would put it at only 7" clearances on the sides.
My plan tomorrow is to "map out", with tape, the two hearth sizes (the fire department, and one according to the wood stove manufacturers manual) so that I can post a picture for any input.
All of the input has been very helpful and thank you for forwarding that page with info. Wish I could buy you all a beer for your help!