Hi I'm new to this site and have some questions. I'm a 29 year old female that just bought a large brick house built in 1817 with 4 large chimneys, one on each corner. Prior to me buying the house one of the 4 fireplaces was removed and bricked over and so was the wall thimble above it that goes into the same chimney. I recently broke out the old thimble hole, put in a new thimble, and cemented it in place with Rutlands fire brick mortar. The wall around the the thimble is plaster but it's about 1/2" thick and it's directly on top of the brick without any lathe or wood. Would this be considered a combustible wall? How far clearance from this wall does the chimney pipe have to be. It does have wallpaper over the plaster. I am also using a antique sears and Roebuck potbelly stove, it's very small and I plan to burn coal. What should I use for clearance guidelines with this stove? I looked online but couldn't find anything specific. Thank for any help!
Wall Thimble
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The chimneys and house were all repainted 2 years ago and I looked inside the chimneys with a mirror and all are. In very good condition with the accept ion of the kitchen fireplace which has a few bricks that came loose on the back. The particular chimney I am speaking if no longer has a fireplace and is in really good shape. Would you think it would be ok to use? It's not lined
There's also a brick bread oven that's attached to the kitchen fireplace and the fireplace in the kitchen is 3x larger then the others. I think that one is so bad cause it was used for cooking so it was used the most
If there's no liner in it, then it's not a safe chimney to burn in. What are the interior dimensions? Time to look at a stainless steel liner.
As for the coal stove, I don't know if the clearances are any different than a wood burner, but 36 inches to combustibles would be the minimum, wall shields may be able to reduce that, but again, I don't know if there are differences between coal and wood requirements. Additionally, you'll need to get an appropriate hearth pad built for it to sit on. Again, being an old unit, the error should be on the side of caution..... But before any of this work, make sure using the stove is going to be OK with your homeowners insurance. Many do not accept non-UL approved units.
Additionally, using an old stove like this is a gamble too. Really, it needs to be torn down, and each piece inspected, and rebuilt with new furnace cement in joints to make sure it's tight enough to be controllable (I've used one that wasn't,,,,,, horrible experience).
Hate to be sharing so much bad news, but no room to do things wrong here.
Pic of the house is beautiful!
Welcome to the site, and good luck.
The good news is this is the right time of year to be figuring these things out!
pen
As for the coal stove, I don't know if the clearances are any different than a wood burner, but 36 inches to combustibles would be the minimum, wall shields may be able to reduce that, but again, I don't know if there are differences between coal and wood requirements. Additionally, you'll need to get an appropriate hearth pad built for it to sit on. Again, being an old unit, the error should be on the side of caution..... But before any of this work, make sure using the stove is going to be OK with your homeowners insurance. Many do not accept non-UL approved units.
Additionally, using an old stove like this is a gamble too. Really, it needs to be torn down, and each piece inspected, and rebuilt with new furnace cement in joints to make sure it's tight enough to be controllable (I've used one that wasn't,,,,,, horrible experience).
Hate to be sharing so much bad news, but no room to do things wrong here.
Pic of the house is beautiful!
Welcome to the site, and good luck.
The good news is this is the right time of year to be figuring these things out!
pen
Thus website says if your chimney us 2 bricks thick and that if the joints are staggered you don't need a liner. Is this not correct anymore?
http://inspectapedia.com/chimneys/Un-Lined_Chimney_Flues.htm
http://inspectapedia.com/chimneys/Un-Lined_Chimney_Flues.htm
whos going to maintain the chimney once decision is made ? you climbing up two stories in NH to clean n maintain ? no talk to your local maint guy or girl .. you could prolly do it if its just yourself and no kids or folk depending on you sure .. only self to kill or mame.. i do al kinds of silly things BUT its only me .. I will be the only one damaged besides My property Far from city limits and neighbors. i lived in new england many years and alot of those old chimneys are questionable at best seems this is a nostalgic effort at best given the stove discussed. need go over the stove really well to.. this is all IMHO to.. remember a womans going to take a beating on this kinda stuff
Shoving Dbl wall pipe or similar liner Negates most of the silly chimney crap . lowes n home depot sell this pipe very reasonable these days to.. or ya can nickel n dime your self to death. with try this n that good luck
From that page I also saw residential building code requiring lining. This is a must. Lining will not only improve stove performance, it is a major safety improvement as well. A wood stove can and will get the flue very hot. Brick, even double brick, will transmit that heat to surrounding combustibles. And brick mortar will degrade over time, increasing risk. A proper insulated liner eliminates the worry and risk. This is really important if and when something goes wrong, and it will. For example, we get regular reports here of folks forgetting to close down the air on the stove. The flue in this case may see a sustained high temp of 1200F or higher for an hour or more. Yes, a liner is an additional expense, but consider it an investment. When something goes wrong, as it most likely will at some time, you will be thanking yourself for making this investment.
Note, the chimney must be thoroughly cleaned before lining. If you hire a certified sweep that person is qualified to do the lining. For a list of certified sweeps in your area enter your zip code in one of these sites:
www.csia.org
www.ncsg.org
To answer the wall thimble question, there is supposed to be brick 12" all around the thimble as it passes through the wall unless there is a special shielding thimble. This article covers the topic: https://www.hearth.com/econtent/index.php/articles/passing_a_chimney
RR1001.8 Flue lining (material).
Masonry chimneys shall be lined. The lining material shall be appropriate for the type of appliance connected, according to the terms of the appliance listing and manufacturer's instructions.
RR1001.8.1 Residential-type appliances (general).
Flue lining systems shall comply with one of the following:
1. Clay flue lining complying with the requirements of ASTM C 315 or equivalent.
2. Listed chimney lining systems complying with UL 1777.
3. Factory-built chimneys or chimney units listed for installation within masonry chimneys.
4. Other materials that will resist, without cracking, softening or corrosion, flue gases and condensate at temperatures up to 1,800F (982C).
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I couldnt agree more BE.. Today im twisted n clamped 6 id thru mfgd. penetrations. Remarkably inexp. these days to. Especially for thee peace o mind factor.
The only way to my knowledge that a brick chimney with out any clay metal or some other liner will pass code is if the inner layer of brick if fire brick. This was done very rarely and still is not a very good solution. And regardless of that i am sure the flue is not sized correctly for that stove and therefore will not preform properly.
Its too easy now to penetrate a wall etc and go up with the dbl wall pipe.than fooling with liners etc. At least seems to me. once comitted to going up that narrow hole the expenses can mount. Im of the belief to exit or penetrate imed or asap once thru wall the codes are better for the less experienced Imho..
If the chimney is sound and has a large enough inside diameter for a stainless insulated liner, that will be much cheaper than insulated double wall pipe, and would preserve the good looks of this classic home.
Nationwide says on their website that older homes constructed with double brick unlined chimneys are safe to use as long as they have been inspected for safety, but your local code has to also say it's ok lol which I'm assuming is next to impossible.
http://www.nationwide.com/wood-stove-safety.jsp
http://www.nationwide.com/wood-stove-safety.jsp
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Sounds like the first thing to do is get the chimney cleaned and inspected for safety. Do you know what are the inside dimensions of the chimney? There should be a reasonable close match between the flue size called for by the stove and the chimney. That should be verified.
I called my town building inspector and was told that they have no local code for chimneys, this might explain why it was so difficult to get homeowners insurance? As soon as I told a few companies the town I lived in, they said they didn't provide insurance for that area. Well I called and actually spoke with someone at my homeowners insurance and explained the situation to them and they said as long as it's inspected and there are no missing bricks, cracks or safety concerns. I can use the chimneys unlined as long as they are at least 2 bricks thick or what's known as 2 wythe
I am sure there are some sort of state code though even in new Hampshire but regardless of code it is not going to work well and could be dangerous. And a wythe is the wall separating the flues not the side walls
This is for a coal stove correct? That will not have creosote issues, but you do want good draft and you do want it to be safe.
A wythe is a continuous vertical section of masonry one unit in thickness. A wythe may be independent of, or interlocked with, the adjoining wythe(s). A single wythe of brick that is not structural in nature is referred to as a veneer.
http://en.wikipedia.org/wiki/Wythe
A wythe is a continuous vertical section of masonry one unit in thickness. A wythe may be independent of, or interlocked with, the adjoining wythe(s). A single wythe of brick that is not structural in nature is referred to as a veneer.
http://en.wikipedia.org/wiki/Wythe
Thank you begreen. Yes this is for a coal stove.
Bholler, I just don't understand how this could be dangerous if I have a certified chimney sweep inspect the chimney. I just don't think my insurance company would allow it. Too many people simply say no don't do it out of fear of being held liable and not taking the time to educate themselves on the issues. I trust my insurance company has a interest to give me the most safe and up to date info on this. How would you perceive this to be dangerous? I'm not being sarcastic, I just want to evaluate all possibilities. Thanks
Bholler, I just don't understand how this could be dangerous if I have a certified chimney sweep inspect the chimney. I just don't think my insurance company would allow it. Too many people simply say no don't do it out of fear of being held liable and not taking the time to educate themselves on the issues. I trust my insurance company has a interest to give me the most safe and up to date info on this. How would you perceive this to be dangerous? I'm not being sarcastic, I just want to evaluate all possibilities. Thanks
Ok then my bad on that
In your case it is more about performance and having good draft. What size is the flue? It should match very closely the volume of the outlet on your stove. How was the chimney inspected? If it was not scanned the whole length with a camera the sweep has no idea whether it is safe or not. The safety issues in your case are not really regarding fire. For you it is more about carbon monoxide. The potential problems for your setup is inadequate draft allowing co to escape the stove of bad mortar joints combined with inadequate draft allowing it to escape through the joints and into the living space
When I get it inspected I'll be sure to make sure they do a complete inspection with a camera, draft is not an issue as when I re-opened the thimble I could feel a very strong draft sucking through the thimble and up the chimney. I also sealed off another fireplace in the house on another chimney. Identical in height and size and when I did, the draft was strong enough to move a small piece of sheet metal. As far as leaking gas I'm not concerned about it as I A: have a CO Detector in each room, B: the joints are staggered on the different layers of bricks which from the research I have done greatly reduced the risk of leaking gasses due to cracks, C: the strong draft and D: I plan to have the chimney inspected regularly. Now I just hope the inspection goes well. I will keep you guys posted!
Ok then you obviously Are not interested in hearing our concerns. I do have to tell you that if you have it inspected by a sweep if they are certified and follow the guidelines of any certifying authority out there they will tell you it need lined And as far as your insurance company goes as long as a sweep signs off on it it is no longer their problem it will go to that sweeps insurance which is why no reputable sweep should sign off on it
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