Chimney questions

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New Member
Nov 9, 2022
3
Sonora, Ca
Hi, looking for some advise as to what options we have available to us when looking at a potential new stove. We purchased this home last winter, and quickly found out that the 'fire place' that was installed when the house was built wasn't meeting our expectations, and I don't believe the previous owners ever used it. What's currently there is a Martin SB4800 zero clearance fireplace.
IMG_4854.jpeg

I really liked sitting by the fireplace in our last house, and my wife would like something that looks better in the living room, so we'd like to pursue something like the following. This is just a random pic of pinterest.

1668040022084.png

The question I have pertains to the chimney. We've settled on either the Green Mountain 60, or if we can't source that the Hipster 20, with 6 inch chimney requirements. Here is the current chimney stack, the top of a new stove to the top of the stack is about 21ft.

IMG_4845.jpegIMG_4852.jpegIMG_4853.jpeg

When we started down this project, I didn't realize that connectivity to the old chimney was going to be an issue. To replace the whole stack with a new 6 ID class A chimney we were quoted about $3400. Not an inexpensive proposition. It was suggested to run an insulated liner down the current chimney, and the place we got the quote from confirmed today that can be done, but there isn't a way to support the old chimney, thus can't do it.

Conceptually this is what I picture. We don't have a second story, but we have a vaulted ceiling and the chimney is hidden in the wall. The wife doesn't like the look of a completely open alcove and the stove pipe running to the ceiling.

Screen Shot 2022-11-09 at 4.52.33 PM.png

1)I'm going to be removing the old insert and framing out the alcove, if its a matter of supporting the stack can't that be accommodated with the reframe?

2)Is it a matter of no UL listed connections available?

3)Is it a way to up-sell?

4)Which sections need to be class A, the part hidden in the wall until it enters the attic, or the whole chimney?

Looking for education, not to be difficult. If consensus is the whole chimney has to be replaced, then thats what it is. If there are alternatives it would be appreciated because ordering a liner appears to be about 1/3rd of what they quoted us. And if ordering our own parts for the class A and installing ourselves is significantly cheaper, then we're down for that as well.

Much obliged for the help,
David
 
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Alcove installs have very specific clearance requirements. Do a lot of homework first. The style of alcove shown can only be done if the entire alcove including framing is non-combustible.
 
Hi, looking for some advise as to what options we have available to us when looking at a potential new stove. We purchased this home last winter, and quickly found out that the 'fire place' that was installed when the house was built wasn't meeting our expectations, and I don't believe the previous owners ever used it. What's currently there is a Martin SB4800 zero clearance fireplace.
View attachment 302412

I really liked sitting by the fireplace in our last house, and my wife would like something that looks better in the living room, so we'd like to pursue something like the following. This is just a random pic of pinterest.

View attachment 302411

The question I have pertains to the chimney. We've settled on either the Green Mountain 60, or if we can't source that the Hipster 20, with 6 inch chimney requirements. Here is the current chimney stack, the top of a new stove to the top of the stack is about 21ft.

View attachment 302414View attachment 302415View attachment 302416

When we started down this project, I didn't realize that connectivity to the old chimney was going to be an issue. To replace the whole stack with a new 6 ID class A chimney we were quoted about $3400. Not an inexpensive proposition. It was suggested to run an insulated liner down the current chimney, and the place we got the quote from confirmed today that can be done, but there isn't a way to support the old chimney, thus can't do it.

Conceptually this is what I picture. We don't have a second story, but we have a vaulted ceiling and the chimney is hidden in the wall. The wife doesn't like the look of a completely open alcove and the stove pipe running to the ceiling.

View attachment 302417

1)I'm going to be removing the old insert and framing out the alcove, if its a matter of supporting the stack can't that be accommodated with the reframe?

2)Is it a matter of no UL listed connections available?

3)Is it a way to up-sell?

4)Which sections need to be class A, the part hidden in the wall until it enters the attic, or the whole chimney?

Looking for education, not to be difficult. If consensus is the whole chimney has to be replaced, then thats what it is. If there are alternatives it would be appreciated because ordering a liner appears to be about 1/3rd of what they quoted us. And if ordering our own parts for the class A and installing ourselves is significantly cheaper, then we're down for that as well.

Much obliged for the help,
David
You will need a new chimney no way to use the old one in this situation
 
bholler- could I trouble you to tell me why? For education purposes please?

begreen- I got these two screen shots out of the NFP-211 guidelines. I didn't see anything about noncombustable framing, but that shouldn't be difficult to include.

Screen Shot 2022-10-04 at 6.20.22 AM.pngScreen Shot 2022-10-04 at 6.20.01 AM.png
 
bholler- could I trouble you to tell me why? For education purposes please?

begreen- I got these two screen shots out of the NFP-211 guidelines. I didn't see anything about noncombustable framing, but that shouldn't be difficult to include.

View attachment 302467View attachment 302468
The chimney for your fireplace isn't rated for use with a stove. In addition once the fireplace is removed there will be nothing supporting the chimney and no approved way to support terminate or connect to it.


The alcove guidelines are going to be set by the stove you choose. Those nfpa guidelines are mainly for unlisted stoves unless the stove manual specified them.
 
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What you are wanting can be done (following all the suggestions above) but will be 8-10k$ On the low end. Just a guess as i don’t know local rates. It would be less expensive to just leave the fireplace untouched and install a free standing stove elsewhere.
 
Yes, there is a difference between a wall with a non-combustible material attached (like cement board, brick, etc.), or an NFPA 211 shielded wall, and a completely non-combustible enclosure. Examples of the latter would be a masonry fireplace, a stove nook in a stone or masonry house, or an enclosure built with a double course of full brick, or metal stud framing that completely isolates the heat to the alcove. Other gating factors will be the stove manual and manufacturer. Some say alcove installation not permitted, while others never tested for an alcove so there is no UL testing data for an alcove.
 
Thanks for the information on the chimney. If we replace it, is there a difference in the type needed for the in the wall portion vs the attic portion? I ask because the quote included 14ft of class A, not 21ft, the price of which I mentioned above.

The hipster manual gives me the specs for alcove clearances. Minimum width, 52 in. Minimum alcove ceiling from floor, 61.5in for unprotected surfaces, and for protected see NFPA-211. What would an example of this unprotected surface be? 5/8 sheet rock? If I frame the alcove with metal studs, would the sheet rock on the front veneer connecting to the metal studs violate the thermal isolation principle?

Moving the location really isn't viable. If this was our forever home, sure I'd move and re arrange several walls. Having to replace the entire chimney piping is already straining the budget for the project.