I took a look at the thimble for the first time today. It is your somewhat typical orange, clay type about 6 inches in interior diameter and about 8 inches thick. Around it there is about 2inches of roll-type insulation (the stuff that looks like cotton candy, but would be itchy going down) between the thimble and the inside of the wall (wood). Is this safe?
Thimble insulated enough?
- Thread starter bkatzman
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bkatzman said:
not compared to modern stove pipe thimbles, no. probably not to code for current / new installation either
most stove makers spell out thimble requirements in thier manuals, all hearthstone wood stove manuals have detailed thimble info btw
we dont see thimbles like that around here much
If I have read your description above correctly, you have told us that the clay thimble is surrounded by 2" of insulation as it passes thru a wooden wall.
This is not at all safe.
Please correct me if I misread your description.
This is not at all safe.
Please correct me if I misread your description.
That's definatly not legal. You need a product such as Daryl posted to pass through a combustible wall, or you can do it yourself. Someplace on this site there is a pdf or a link to one with perfect directions. If anyone can find it I swear I am going to save it on my computer cause its damn good and I can never find it when I want it.
Thanks everybody.
Although I am new at owning a house and even newer at using a wood stove I knew that this didn't look right.
First step will be remove all of the wood paneling and see what we have as far as studs are concerned. I like the second method of passing double wall pipe from the stove pipe directly into the chimney and leaving 9" of air space. It seems like the easiest, fastest (and most economical) method. As far as I had read it, am I right that the stove pipe and the chimney carry the weight of the double wall pipe considering there will be 9" of air space around it?
Thanks again. It may cost some $$$ and time, but at least I'll know that we're safe...
Bryce
Although I am new at owning a house and even newer at using a wood stove I knew that this didn't look right.
First step will be remove all of the wood paneling and see what we have as far as studs are concerned. I like the second method of passing double wall pipe from the stove pipe directly into the chimney and leaving 9" of air space. It seems like the easiest, fastest (and most economical) method. As far as I had read it, am I right that the stove pipe and the chimney carry the weight of the double wall pipe considering there will be 9" of air space around it?
Thanks again. It may cost some $$$ and time, but at least I'll know that we're safe...
Bryce
So I am in the process of removing any wood that surrounds the clay thimble. Being that it seems like it would be a lot more work tto remove the thimble (it is 8 inches long and half of it is cemented in brick) I was thinking of "boxing" around the remaining four inches (that was previously very close to wood.
I was thinking of boxing the thimble with cement or something similar. What do you all recommend and how big does the box have to be to up to code (I live in NYS) and the thimble is six inches wide?
Thanks for your help. I am hopeful that I can handle this project!
Bryce
I was thinking of boxing the thimble with cement or something similar. What do you all recommend and how big does the box have to be to up to code (I live in NYS) and the thimble is six inches wide?
Thanks for your help. I am hopeful that I can handle this project!
Bryce
I looked at the link above and I believe it is explained crystal clear:
This installation is known as a “wall patch” which entails 12” of solid masonry around all sides of the crock. For a 6” crock (8” OD), that means a total width and height of 32” square of solid masonry. If the interior wall needs to match up to a being a flat surface, then non-combustible cement board such a Durock could be used on the interior finish. Another alternative would be to plaster right over the masonry to match the interior wall surface.
This installation is known as a “wall patch” which entails 12” of solid masonry around all sides of the crock. For a 6” crock (8” OD), that means a total width and height of 32” square of solid masonry. If the interior wall needs to match up to a being a flat surface, then non-combustible cement board such a Durock could be used on the interior finish. Another alternative would be to plaster right over the masonry to match the interior wall surface.
It turns out that won't work either because I have only 7 inches from the bottom of the thimble to the top of the 2/4 that runs behind the brick wall. Is there a "collar" of some kind that I put around the remaning four inches of thimble? Obviously I would stud-in the collar and then insulate and cover the wall from there on..
So the specs would basically be anything that would be able surround a 6inch crock thimble and need less than 7 inches of clearance.
Thanks again
Bryce
So the specs would basically be anything that would be able surround a 6inch crock thimble and need less than 7 inches of clearance.
Thanks again
Bryce
Those prefab through the wall insulated thimbles might get you closer clearances. Usually called a "wall pass-through"
Thanks for the advice!
It seems like all the pass through stuff I've been looking at assumes that you're replacing the thimble. The thimble I already have installed is 8 inches long. 4 are in the brick and go into the flue and the other 4 is in the house (used to be surrounded by wood, which I have learned is very unsafe.
3 of the four sides have about 2 feet of clearance, but the bottom of the thimble only has about 7 inches between it and the top of a "mantle" setup, so I am looking for a cuff, collar, or sleeve that I can put around the thimble and be safe to have wood against it.
It seems like all the pass through stuff I've been looking at assumes that you're replacing the thimble. The thimble I already have installed is 8 inches long. 4 are in the brick and go into the flue and the other 4 is in the house (used to be surrounded by wood, which I have learned is very unsafe.
3 of the four sides have about 2 feet of clearance, but the bottom of the thimble only has about 7 inches between it and the top of a "mantle" setup, so I am looking for a cuff, collar, or sleeve that I can put around the thimble and be safe to have wood against it.
There is no such thing that I know of. You can make up your own whatever but it would not be tested / listed so its safty would be unknown.
Thanks!
I think what I may do is get a double or triple wall pipe and put it over the thimble and see how it goes as far as putting wood around it to finish the wall around the thimble.
I think what I may do is get a double or triple wall pipe and put it over the thimble and see how it goes as far as putting wood around it to finish the wall around the thimble.
bkatzman said:
Using double wall insulated pipe around that crock sounds (in place of the fiberglass) sounds like your best option. Make sure it is rated for having combustables within 2 inches of it.
pen
So it turns out that simply throwing double/triple wall over the 6" clay thimble will probably not be code (according to my local stove shop guy), instead he has suggested.. BTW - For those of you have just joined us the issue is that
- hammer out the old clay thimble
- chisle the brick around the old thimble to fit metalbestos 6" ultratemp class a double wall pipe (which will become the new thimble)
- mortar it into the chimney/flue
- install about 8 feet of single wall
- install a heat shield
All for $400 and if the work doesn't meet code he will make it so for free
I am pretty sure that the stove guys idea and price are sensible. Anyone agree/disagree?
Thanks
Bryce
- hammer out the old clay thimble
- chisle the brick around the old thimble to fit metalbestos 6" ultratemp class a double wall pipe (which will become the new thimble)
- mortar it into the chimney/flue
- install about 8 feet of single wall
- install a heat shield
All for $400 and if the work doesn't meet code he will make it so for free
I am pretty sure that the stove guys idea and price are sensible. Anyone agree/disagree?
Thanks
Bryce
So it turns out that simply throwing double/triple wall over the 6" clay thimble will probably not be code (according to my local stove shop guy), instead he has suggested.. BTW - For those of you have just joined us the issue is that
- hammer out the old clay thimble
- chisle the brick around the old thimble to fit metalbestos 6" ultratemp class a double wall pipe (which will become the new thimble)
- mortar it into the chimney/flue
- install about 8 feet of single wall
- install a heat shield
All for $400 and if the work doesn't meet code he will make it so for free
I am pretty sure that the stove guys idea and price are sensible. Anyone agree/disagree?
Thanks
Bryce
- hammer out the old clay thimble
- chisle the brick around the old thimble to fit metalbestos 6" ultratemp class a double wall pipe (which will become the new thimble)
- mortar it into the chimney/flue
- install about 8 feet of single wall
- install a heat shield
All for $400 and if the work doesn't meet code he will make it so for free
I am pretty sure that the stove guys idea and price are sensible. Anyone agree/disagree?
Thanks
Bryce
As long as you can meet clearances with the new thimble. Just cause its class A doesn't mean you only have 2" clearance. If you check out the link provided before you need 9" of air space all around when using insulated double wall. According to your older post you only have 7" to the current thimble, and that would leave you with 6" or less to a larger OD Class A piece of pipe.
It seems like I am SOL then, because unless we move the thimble up, I won't have enough clearance. I kept asking the stove guy over and over how much clearance will be needed from the pipe....
I didn't want to have the code inspector come out to find out it was not in code and also it not be safe.
I will look into our options as far as bringing the thimble up three inches or so, just so that there is 9 inches from the class "A" pipe.
Man, when I got this free wood stove from my friend I thought I had it made. Luckily this will be a supplemental heat source or I would REALLY be screwed.
Although your observation isn't good news for me, I am glad that is informing me how to have this be safe!
Appreciated,
Bryce
I didn't want to have the code inspector come out to find out it was not in code and also it not be safe.
I will look into our options as far as bringing the thimble up three inches or so, just so that there is 9 inches from the class "A" pipe.
Man, when I got this free wood stove from my friend I thought I had it made. Luckily this will be a supplemental heat source or I would REALLY be screwed.
Although your observation isn't good news for me, I am glad that is informing me how to have this be safe!
Appreciated,
Bryce
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