a dumb clearance question

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ansehnlich1

Minister of Fire
Hearth Supporter
Dec 5, 2006
1,601
Adams County, PA
Ok, say the wall behind my stove is brick, and the stove requires 16 inches from the back of the stove to the wall. Would that be 16 inches to the brick, or 16 inches to the drywall behind the brick?
 
ansehnlich1 said:
Ok, say the wall behind my stove is brick, and the stove requires 16 inches from the back of the stove to the wall. Would that be 16 inches to the brick, or 16 inches to the drywall behind the brick?

I would think it's to the brick surface........because then the wall is even further behind that and therefore safer......
 
I will have to look into my codes ,so this is not an exact code quote. There are a couple of factors here the bricks do afford some protection. According to reduced clearances,,

( remember this is from memory and not confirmed yet). the brick wall can be used to reduce clearance by up to 1/3 but no less thaN 12" THAT DISTANCE IS MEASURED FROM THE

COMBUSTIABLES and not the facing, ie from the sheetrock. You could set that stove 13" from the sheetrock in front of the brick wall
 
yeah elk, that's a technical question ain't it? i'll wait to see what you say, but a stove man told me i measure that rear clearance from the combustible surface, NOT the brick. I'm just trying to figure out whether he know's what he's talking about or not.
 
Shane said:
The clearance is to a combustible so you measure to the combustible.


Guys,

This is insanity.....let's assume there's NO brick...just a wall.......if the code says 16" to the wall, then it's 16". Now add brick in front of the wall. You error on the side of safety by maintaining 16" to the brick face if you can. Why? Because bricks add a safety margin and if 16" to a dry wall meets code, then certainally 16" to a brick face (approx 19" to wall behind it) certainally adds even more protection......... so, as Elk says...better safe than sorry. If it were me, I'd maintain 16" to the brick.
 
Shane said:
I guess I'll take my insane professional advice & understanding of code & go elsewhere then.

Shane,

sorry if I came across that way...all I'm saying is that if he has the distance to maintain 16" from the brick, that gives him an additional 3" or so from the real wall behind the brick....that way you get 19" or so to combustables and remember, the 16" is a minimum. So, if one wants to be really safe they would do it 16" from the brick, thus putting the distance to the combustable wall behind it almost 19"....that's all. Sorry if I offended.
 
a bick does have insulation value of about r.8 and it does dissipate heat and is is non combustiable

I cn not dissagree with castiron safety is is better to error on a larger clearance that to be less
However. if I come accrost a situation, that I may not like or agree with. and it meets the letter of the code I have to pass that issue.
What has held me back fro posting the actual code is it is in chart form and cut and paste looses its format . Plus it means fireing up my windows notebook and getting off this MAC
i guess to clarify everything I will try to post a direct cut and paste i so all can interpet instead of guessing
 
elkimmeg said:
a bick does have insulation value of about r.8 and it does dissipate heat and is is non combustiable

I cn not dissagree with castiron safety is is better to error on a larger clearance that to be less
However. if I come accrost a situation, that I may not like or agree with. and it meets the letter of the code I have to pass that issue.
What has held me back fro posting the actual code is it is in chart form and cut and paste looses its format . Plus it means fireing up my windows notebook and getting off this MAC
i guess to clarify everything I will try to post a direct cut and paste i so all can interpet instead of guessing

I agree Elk however, this person is asking what to do....the prudent thing to do is to say 16" is minimum......and let him/her decide BUT also give them the options (16" from wall vs 16" from brick) and state that while both meet code, code is a minimum and 16" from brick is much better...........
 
another point missed is the need of space behind the stove to allow circulation of heat to keep it cooler and not to over fire it.

If the wall were completely non combustiable, it would be prudent to have some free flowing air space behind that stove. Having more is an extra safety margine
we agree on that point
 
This may be a judgement call for your code authority, but here's how the code jurisdictions in our service area would rule:

If the bricks are touching the combustible material, they will transmit heat. Clearances are measured from the brick surface, as if it were combustible.

If there is a ventilated 1" airspace between the bricks and the combustible material, clearances are measured from the combustible material behind the bricks.
 
hey i just want you guys to know i'm reading everything posted here.....i'm the one that started this thread, and i'm trying to clarify the size of my hearth, and it appears as though an added measure of safety never hurts and I'll measure my stove clearance (rear of stove to combustibles) to the brick, and not the drywall/framing behind the brick.....

plus i wanted to see the exact code as written, you see, this stove guy is telling me the clearance is measured from the combustible material BEHIND the brick, not the brick itself.
 
elkimmeg said:
another point missed is the need of space behind the stove to allow circulation of heat to keep it cooler and not to over fire it.

If the wall were completely non combustiable, it would be prudent to have some free flowing air space behind that stove. Having more is an extra safety margine
we agree on that point

I think this is the real issue. If there is an air gap, I'd say 16 inches to the drywall. If there is no air gap, I'd say 16 inches to the brick.
 
thechimneysweep said:
This may be a judgement call for your code authority, but here's how the code jurisdictions in our service area would rule:

If the bricks are touching the combustible material, they will transmit heat. Clearances are measured from the brick surface, as if it were combustible.

If there is a ventilated 1" airspace between the bricks and the combustible material, clearances are measured from the combustible material behind the bricks.

to en extent you are correct heat does transmit through but the bricks themselves do have an R value of .2 per inch 4x .2 =.8 every inch of air space dead air space is .9 per inch

the other point the bricks absorbe heat but also dissipate heat over a larger surface than the stove radiation area. so to end this I will turn on my ccote book and reproduce the actual code

Or let the interpetations discussions roll.
 
It sounds like this issue might have been been kicked around before on the forum (let the interpretations discussions roll?), but I think it is important to keep in mind that NFPA211 isn't the only codebook used by every code department in this country, and that, even among those who subscribe to a literal enforcement of their chosen codebook(s), there are always situations that require interpretation of that codebook by the local office or inspector on site.

Our service area spans five code jurisdictions, and all five subscribe to a different combination of NFPA211, the Uniform Mechanical Code (UMC), the National Fuel Gas Code and the Washington Association of Building Officials (WABO) codebooks. Not only is each code jurisdiction entitled to mix and match code requirements from these and other code standards, they're also able to make any changes or amendments as they see fit.

Specifics such as wall shielding techniques and clearance reductions often vary from one jurisdiction to the next, so our installers need to know which code jurisdiction a given house is in before using a given installation or clearance reduction material or technique. In other words, a wall shield that will pass with flying colors in Winnemucca might not fly at all in Walla Walla.

I've seen people go to great trouble and expense to complete an installation to the letter of code, only to have the permit inspector fail the installation because the local code office had a different interpretation (or subscribed to a different spec altogether).

I mention all this because, although it happens that all of the code authorities we deal with are in agreement about the affect of a 1" airspace in cases like this one, I think any answer given to code questions should always include advice to check with the code authority having jurisdiction.
 
You are right NFPA 211 is not a national reconised code outside fire depts has no jusisdiction unless given so by the building inspector. The one reconised code nationally is the Internation code c group the only one with national reconition in all 50 states Gass codes have no right being applied to solid fuel or oil burning appliances they have there own sepatate code that overlaps into the mechanical codes. If a code inspector quotes from the gas code pertaining to a wood stove or sloid fuel appliance I would ask for clarification in the code that applies.

We can not make up code as we seem fit there has to be some base. Now all solid fuel burning appliances use or refference NFPA 211 for compliance it now becomes fair game to apply it.

Arguing with and inspector is like wrestling with a pig in mud, after a while you realise he enjoys it
 
ansehnlich1 said:
Ok, say the wall behind my stove is brick, and the stove requires 16 inches from the back of the stove to the wall. Would that be 16 inches to the brick, or 16 inches to the drywall behind the brick?

to start with , your question IS NOT A DUMB QUESTION!!! im at home and do not have a copy of nfp211 here , couldnt see dropping 135.00 for an extra keep home copy (i may just do so if i hang out in here much longer so i can refer to it) elk probably has one to look at so i will defer to him on this. i am leaning towards tom oyens post in this thread and am also one to err towards caution. if you have room to allow for those extra 4 inches, use em. another question, does the unit have an available heat shield? this would make the question a moot point. another thing to look at is pipe clearance, depending on how high that brick facing extends, you may have an issue with single wall pipe if you can move the unit to within 12 inches as single wall pipe must have an 18 inch clearance to combustibles regardless of how close the unit can be placed. using shielded pipe , or double wall pipe may be a must if you fall under this measurement (wasnt asked about but i figured i'd toss that out.)
 
elkimmeg said:
You are right NFPA 211 is not a national reconised code outside fire depts has no jusisdiction unless given so by the building inspector. The one reconised code nationally is the Internation code c group the only one with national reconition in all 50 states Gass codes have no right being applied to solid fuel or oil burning appliances they have there own sepatate code that overlaps into the mechanical codes. If a code inspector quotes from the gas code pertaining to a wood stove or sloid fuel appliance I would ask for clarification in the code that applies.

We can not make up code as we seem fit there has to be some base. Now all solid fuel burning appliances use or refference NFPA 211 for compliance it now becomes fair game to apply it.

Arguing with and inspector is like wrestling with a pig in mud, after a while you realise he enjoys it

elk is correct <sigh> again, if the unit is tested and certified listing compliance to nfpa211 and or ASTM-E 1509-93 the in absence of superceding code these are the codes that should be followed
 
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