Options for old fireplace

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jbmfg

New Member
Dec 15, 2016
7
portland maine
I recently bought a home built in the 1950s with an 8x12" wood burning fireplace in Maine. I had a chimney guy come out to inspect it who told me the clay liner is in bad shape. He said that it cannot be fixed or replaced due to code requiring a 10-12" round liner. I know the fireplace was used in the past but dont know how much/often. The chimney guy told "off the record" that it could probably be used very sparingly but could not officially say it was okay to use. Now my question is do i have any options other than putting in an insert stove? One of the main reasons we loved this house was the idea of having a nice open fire in the winter so we're quite depressed about this. Is it possible to find someone that will fix the existing liner?
 
well unless it is some local code there is nothing requiring a 10-12" round liner. but there is a ratio that should be maintained between the opening of the fireplace and the flue size. It is not required by code but it is what works. He may have been saying he could not meet that ratio and because of that was not confident it would work. What is the opening size of the fireplace?
 
well unless it is some local code there is nothing requiring a 10-12" round liner. but there is a ratio that should be maintained between the opening of the fireplace and the flue size. It is not required by code but it is what works. He may have been saying he could not meet that ratio and because of that was not confident it would work. What is the opening size of the fireplace?

Im not really sure what the opening is. Would i just measure the space just before it narrows into the chimney?
 
Im not really sure what the opening is. Would i just measure the space just before it narrows into the chimney?
no measure the opening of the fireplace that faces the room.
 
it's roughly 30x38".
yeah a 8x12 is not big enough for that size opening it should have been a 12x12. or a 12" round if you were relining it. You could try breaking out the old liners and getting as big a liner in there as you could but it still might not work. Then you have wasted all that money on a fireplace that will never work right. I think the best option would be a liner and insert. And then you would have something that could actually contribute some heat to the house as well.
 
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An insert with a 6" insulated liner is a good option. That would provide much better heating and still would provide a nice fire view.
 
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There is a one to ten rule with fireplace opening size and flue size. Your opening is 1140 sq. inches so you need a flue that is 114 sq. inches.
Your flue is 96 square inches so it is close. Might have worked OK. You could not make it any smaller.
Unless.
Unless you make the fireplace opening smaller. They make metal pieces that are designed for just such a job. If you put one of these pieces at the top, say it was 6 inches by 38, then you could make do with a smaller flue.

My daughter in law in Atlanta bought just such a metal piece at a wood stove store and it worked to make the fireplace draw properly.
 
Good tip, but it's not going to fix the bad flue tiles.
 
That is true. But, if he could fit a round liner in there, he could use the pi R square rule to figure the size of the new flue pipe, and then perhaps make smaller the fireplace opening to keep with the 1:10 ratio.
 
There is a one to ten rule with fireplace opening size and flue size. Your opening is 1140 sq. inches so you need a flue that is 114 sq. inches.
Your flue is 96 square inches so it is close. Might have worked OK. You could not make it any smaller.
that would be true if it was 8x12 inside but the largest i have seen are 7x11 usually less though. so you would have to break out the old tiles and line it with a rectangle liner tie that into the smoke chamber ect, you are looking at 2500 to 3000 and it still wont provide much if any heat
 
Yes, the 8x12 tile is the gating factor.
 
One of the main reasons we loved this house was the idea of having a nice open fire in the winter so we're quite depressed
Can I have $20.00, I'll pm you my info of where to send it to, I figure if you like an open fireplace you like throwing money used for heat of the window, or in this case up the flue.
In all seriousness though you can have an insulated metal liner installed with a plenum in the smoke chamber? or just install an insulated liner and get a nice big window insert and not only have a nice light show, but actually get useable heat into the living space?
 
bholler is correct that flue is only 77 square inches if it is 8x12 ("9x12",8x13",etc - they all mean the same thing)
you only need 1 to 10 with square or rectangle flues though; 1 to 12 with round for whoever said that.
The metal piece to lower opening is called a smoke guard.
Unfortunately I find masons tend to undersize flue often - No idea why, its so easy to install correct size when building. I have come to believe they just don't know any better since i see it soo often
 
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8 X 12 was the standard size liner for typical fireplaces for decades. Your opening size is just beyond what most fireplace openings are. Most of the time the 8 X 12 flue is barely adequate but worked fine if the throat and smoke chamber was built properly. When I worked with masons we almost always went with 12 X 12. I've seen some homes with fireplaces flues as small as 8 X 8. While I was looking at homes to buy I crawed into every fireplace wth a flashlight to check out the chimney construction. My realtor never had a client do that. He got a kick out of it. I like my caveman TV.
 
Thanks everyone for your input. Apparently it is local code to have a 10-12" round liner. I know this fireplace was used at one time so I am sure it works with the dimensions i stated. When you all say the flue is undersized for the opening, what is the issue? I mean to say, what would you expect to be the symptom of an undersized flue? Also, despite the local code issues, if i wanted to have the liner repaired what am i looking at in terms of options/cost?
 
Just wondering if its possible to fix the broken flue liner? What would be my options? Could put in an insert i guess but i just think theyre so ugly
 
If the flue is undersized, the fireplace will smoke constantly. I will deliver smoke into the room, making the fireplace unusable.
 
I know its been used in the past to good effect so I do not believe that is an issue. I've been told its not possible to fix the broken tiles of the flue liner but that's hard to believe. Possibly cost prohibitive but impossible?
 
I know its been used in the past to good effect so I do not believe that is an issue. I've been told its not possible to fix the broken tiles of the flue liner but that's hard to believe. Possibly cost prohibitive but impossible?
Just because it was used does not mean that it didnt smoke. we see smoke stained fireplaces all the time and some people see nothing wrong with it.
 
Thanks everyone for your input. I understand that it may smoke despite being used in the past but what i really am hoping for help on is around fixing the broken flue tiles.
 
Thanks everyone for your input. I understand that it may smoke despite being used in the past but what i really am hoping for help on is around fixing the broken flue tiles.
The old clay tiles will need to be removed and replaced with an insulated stainless liner as large as you can fit in there.
 
Thanks everyone for your input. I understand that it may smoke despite being used in the past but what i really am hoping for help on is around fixing the broken flue tiles.
What's happening is you brought your car into the garage because your brakes are metal to metal but the mechanics are telling you is that you need to replace your brakes and get a brake controller for that 10,000 lb trailer you have been pulling because the vehicle brakes alone are not sized properly for that kind of load.

Get a second opinion if you don't like that guys answer. Better yet, ask the guy why he is insisting on a 10-12" round liner. Ask him if the existing liner can be replaced with the same size and if the size of the fireplace opening discates the size of the liner. If he says the size dictates the liners size ask him why round is required when you can get an equivalent sized flue in different shapes. Ask him if the smoke guard is necessary to use with that fireplace and size flue. Ask him if that size flue (once repaired) could be use with a smoke guard installed to reduce the fireplace opening.

Sounds like you've been given some really sound advice on why the flue is undersized and a possible solution. I would challenge the inspector with the questions I gave you can see what he says. It might be he's not interested in doing the repair of the liner and giving you an unrealistic answer. I'm not an expert on chimneys or fireplaces but I would take the advice that been given and let the expert give you the answers. After all, you are going to pay someone to do a job you need to know your are doing the right thing.
 
Sounds like you're dead set on using the fireplace as is. It also sounds like you're going to try to use it either way. Would it be possible to tear down one side of the chimney, build out the two shorter sides, and create a chimney that could handle a 12" liner? I'm not sure what your house is like where the chimney sits. If you're dead set on keeping it the way it is as much as possible, you might have to do something major.
 
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Would it be possible to tear down one side of the chimney, build out the two shorter sides, and create a chimney that could handle a 12" liner?
I am sure it would be possible but it would be much easier and probably cheaper to just take it down to the top of the smoke chamber and build new or run an appropriately sized class a chimney from there up.