Help or advice on two flue multi-floor fireplaces...

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EBurns

New Member
Jul 30, 2022
5
Minnesota
Hello, I'm a first time poster here and absolutely new to the world of fireplaces as this is the first home I've lived in one that had one, let alone two. Please pardon if I refer to things as one word but mean another. I'm still learning the language of fireplaces. Also, sorry for the long post but I'd like to be thorough.

Basic features:
Our home is in Minnesota and we have main level and basement level brick, wood burning fireplaces which share a chimney stack on an exterior wall. There are two "crowns" at the top of the stack that are at the same height. Neither fireplaces had been used in many years and both were sealed off with foam insulation. Last year, I called a company who I will not name, to give us an estimate on how to get our fireplaces in operation and check for safety. they charged me 400$ and they basically came in and quickly told me many things like:

"Your fireplace is in good shape, but it could use a quick cleaning, we wont clean the chimney stack but we can clean up the flue and patch this hole with a fire brick and vacuum it all out. You should be able to use this fireplace". They also said "It looks like a gas line was ran here with the intention of eventually making this a gas fireplace but we will seal that off" I told them I wanted to have the basement fireplace operable as well which they replied "You don't want to use that fireplace its more trouble than its worth and you will constantly be fighting smoke in the house". So I said ok and let it go. They also told me "that the best way to keep the smoke from drafting back in the house was to crack a window". So I said ok, paid them and they left. Whole time took about an hour. Winter of that year came and we began to use the fire place. Basement fireplace still sealed and we used the fireplace by cracking a window. Pretty obnoxious solution since the house then gets cold. They girls hated it because they wanted a warm house but I like the fire.

Today I thought that there wouldn't be any basement fireplaces if they were that much of a pain and so why would they be installed in possibly hundreds of thousands of houses if they weren't effective, so I'm seeking advice here on this forum.

I'd like to know a few things based on the photos I'm uploading:

1. Is it possible and what is the difficulty level of installing cold or fresh air intakes on our exterior wall for both fireplaces? a. Is it necessary to have two different air intakes for the two separate fireplaces or will one work for both if place correctly?
b. I'd like to not run vents, so if the best advice is to stay away from air intakes, what other options are
recommended?
2. Can both fireplaces be operating at the same time? If yes, is it safe?
3. Is it recommended to move one of the crowns up above the other?
4. What is this little box area to the right on the downstairs basement (image of fireplace without the wood standing thing)?
a. Is that an ash catch?
b. Should it be patched up and firebricked?
5. What are any other best recommendations or advice you can give for utilizing both fireplaces In my home?

I really appreciate any feedback or advice. Once again, I'm new to this world so thank you for understanding that I may not have the most precise language or knowledge here.

crowns.jpg downstairs ash catch.jpg downstairs cleanedout.jpg downstairs hardware.jpg downstairs sealed up.jpg outside stack 1.jpg outside stack 2.jpg upstairs fireplace 2.jpg upstairs fireplace 3.jpg upstairs fireplace1.jpg upstairs flue.jpg
 

begreen

Mooderator
Staff member
Nov 18, 2005
94,695
South Puget Sound, WA
It's possible that the basement fireplace is prone to negative pressure and sometimes drew smoke when the upper fireplace was burning. This can be made worse when both flues terminate at the same height at the crown. That may be the reason they were blocked.

Fireplaces are very inefficient and suck out room air as they cool down. Has a compromise been considered in the form of an insert? Installing an insert would dramatically improve heating, reduce wood consumption, and still provide a nice fireview.
 
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EbS-P

Minister of Fire
Jan 19, 2019
3,042
SE North Carolina
We have a house with an upstairs and downstairs masonry fireplaces. The upstairs spilled some smoke enough to set off smoke detectors. we burned it the first winter. Never lit a fire downstairs. Found out I’m really sensitive to wood smoke. Switched to ethanol burners for 5 or more years. Then decided we wanted a wood stove. So we put that in the fireplace upstairs. We love it. So much that the Basement got an insert last year. Both with insulated liners. We don’t have a fresh air intake as the house is not very air tight. Both have fire screen options but I don’t see myself ever get them.

How much do you want to burn a year?
 

EBurns

New Member
Jul 30, 2022
5
Minnesota
It's possible that the basement fireplace is prone to negative pressure and sometimes drew smoke when the upper fireplace was burning. This can be made worse when both flues terminate at the same height at the crown. That may be the reason they were blocked.

Fireplaces are very inefficient and suck out room air as they cool down. Has a compromise been considered in the form of an insert? Installing an insert would dramatically improve heating, reduce wood consumption, and still provide a nice fireview.
Thanks for the great info begreen. I'm not familiar with an insert or its function. I will research it more but can you tell me briefly what it does and if there is a kind or make/model you think works best?
 

EBurns

New Member
Jul 30, 2022
5
Minnesota
We have a house with an upstairs and downstairs masonry fireplaces. The upstairs spilled some smoke enough to set off smoke detectors. we burned it the first winter. Never lit a fire downstairs. Found out I’m really sensitive to wood smoke. Switched to ethanol burners for 5 or more years. Then decided we wanted a wood stove. So we put that in the fireplace upstairs. We love it. So much that the Basement got an insert last year. Both with insulated liners. We don’t have a fresh air intake as the house is not very air tight. Both have fire screen options but I don’t see myself ever get them.

How much do you want to burn a year?
When we burn the upstairs only a few cords a year but that is because we've always had to have a window cracked which annoyed the family with the cold drafts. I'd imagine if we had a solution (looking into the insert) that we would burn a lot more, certainly in the basement where I spend most of my time and in the winter. Guessing maybe a few hundred cords a season.
 

EBurns

New Member
Jul 30, 2022
5
Minnesota
It's possible that the basement fireplace is prone to negative pressure and sometimes drew smoke when the upper fireplace was burning. This can be made worse when both flues terminate at the same height at the crown. That may be the reason they were blocked.

Fireplaces are very inefficient and suck out room air as they cool down. Has a compromise been considered in the form of an insert? Installing an insert would dramatically improve heating, reduce wood consumption, and still provide a nice fireview.
I just looked into it and it appears my upstairs fireplace has an insert looking at the picture. The downstairs would not have one. Would you recommend getting one for both and raising up the upstairs crown above the downstairs crown on my stack?
 

kborndale

Feeling the Heat
Oct 9, 2008
428
LI
When we burn the upstairs only a few cords a year but that is because we've always had to have a window cracked which annoyed the family with the cold drafts. I'd imagine if we had a solution (looking into the insert) that we would burn a lot more, certainly in the basement where I spend most of my time and in the winter. Guessing maybe a few hundred cords a season.

You are not burning a few hundred cords a winter.
 

EbS-P

Minister of Fire
Jan 19, 2019
3,042
SE North Carolina
I just looked into it and it appears my upstairs fireplace has an insert looking at the picture. The downstairs would not have one. Would you recommend getting one for both and raising up the upstairs crown above the downstairs crown on my stack?
an insert is a woodstove that is designed to go inside a masonry fireplace. It appears your upstairs fireplace has glass doors not an insert.

A cord is a stack of cut and stacked firewood that measures 4’w by 4’ H by 8’ L

Cheapest DIY new insert install with insulated liner is about 2400$ now. Research the tack credit.
 

Ctwoodtick

Minister of Fire
Jun 5, 2015
1,726
Southeast CT
From the pics you provided, I’m not seeing an insert. Maybe I’m missing something.
You burn 2 cords of wood per winter in the fireplace- you’re obviously into wood burning. A wood burning insert would give you both very good useable heat while giving you that nice view of the fire, as mentioned by Begreen. I burn maybe 3.5 cords a winter and heat my 1970’s 2 story house of about 1400 sq ft with it. I’m adding a picture of it so you have it as reference. Don’t get thrown off by the blue flame, it’s not a gas insert- sometimes you get that with wood burning and it’s a cool little thing to see. Some inserts are flush to the fireplace opening like mine. Others protrude a few inches.
I’ll let the pros answer your good questions. In my non- professional opinion- I would not use the fireplace with that opening in the firebox (the one you were wondering g might be an ash deposit of some sort).
Ash clean outs are built into the masonry of the firebox hearth (right under the area that the fire would be burning), so I don’t imagine the whole in your firebox is for ashes. Old Gas hookup maybe? However, that opening is a lot bigger than you’d expect for some gas lines.
Whatever you do, try to get another company to inspect/fix/ upgrade your entire fireplace/chimney system. In my opinion, there are a good number of hacks that promote themselves as knowledgeable professionals. That said, there are some very good thorough pros out there that are very diligent in the work. It sounds like the guy you had come by was a hack and an expensive one at that.
If you have access to other chimney sweeps in your area, I recommend calling them and asking the following question-
“Hi, I’m considering having a wood burning insert installed and would like you to come out to inspect my chimney. Can you tell if you recommend insulating the liner?”.
If they say that insulating is not necessary, call another chimney sweep until you find one that says that they insulate as part of their normal installation. It’s a very quick and easy way to determine if that chimney sweeps knows/cares about doing proper work in your house.

59396B2B-A2F6-4294-9764-004AB9E972D4.jpeg
 

EbS-P

Minister of Fire
Jan 19, 2019
3,042
SE North Carolina
asking the following question-
“Hi, I’m considering having a wood burning insert installed and would like you to come out to inspect my chimney. Can you tell if you recommend insulating the liner?”.
If they say that insulating is not necessary, call another chimney sweep until you find one that says that they insulate as part of their normal installation. It’s a very quick and easy way to determine if that chimney sweeps knows/cares about doing proper work in your house.

View attachment 297465
Great advice!!
 
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begreen

Mooderator
Staff member
Nov 18, 2005
94,695
South Puget Sound, WA
I just looked into it and it appears my upstairs fireplace has an insert looking at the picture. The downstairs would not have one. Would you recommend getting one for both and raising up the upstairs crown above the downstairs crown on my stack?
As others have noted, the upstairs fireplace does not have an insert, they are doors attached to the fireplace face. Yes, raising the upstairs fireplace flue 12-18" should cure most back-siphoning of smoke. This can be achieved with a short liner extension when the stainless steel flue liner is installed for the upper fireplace.
Consider holding off on getting an insert for the bottom floor until you have a chance to learn more about the house, its heating needs, and how the basement fireplace works in cooler weather. If the lower fireplace spills out smoke badly, even when the chimney is warmed up, then there likely is a negative pressure problem. If so, then that problem may persist even with a new insert. This is all TBD. One clue might be that large hole on the right side. I don't think that is an ash catch, but its purpose should be determined. At first, I thought of a fresh air supply, but not sure and have concerns about that if this was the intent.

As to the question of basement fireplaces, there are many quirky things done in houses, often at the whim of the architect or designer trying to satisfy the whims of the homeowner. The idea may look good on paper, but sometimes doesn't pan out in reality. I see this all the time. And not all basement fireplaces are failures, especially if the house is well sealed upstairs and the fire doesn't have a lot of competition for combustion air from things like furnace, hw htr, clothes dryer, strong kitchen fans, etc.

This site has good info on chimney design and problems along with a lot of good wood heating advice.
 

stoveliker

Minister of Fire
Nov 17, 2019
5,356
Long Island NY
The point about insulated (steel) liners is that it makes inserts burn better, is safer, and often is the only way to get the system up to code (point back to safety...)
 

EBurns

New Member
Jul 30, 2022
5
Minnesota
Now that I know what constitutes a cord, I'm certainly not burning hundred of them. 2 at most for the entire house under fully operating fireplaces.

Lots of great info and replies, thanks for the feedback. I think I will heed the advice and call a pro to give a quote on the insert (request insulation) and wait on the downstairs until winter. I will ask them about the side cutout area in the basement though so that I can prepare myself to patch or have it patched with firebrick before the cold sets in.

I will also move up the upstairs flue to be sure I reduce chances of smoke dumping back in the house. Our house is sealed pretty well from what I can tell so I may still end up needing a fresh air intake at some point. I'd like to determine that now before its too cold but I realize the air pressure will be different in winter.
Thanks again.
 

Ctwoodtick

Minister of Fire
Jun 5, 2015
1,726
Southeast CT
Now that I know what constitutes a cord, I'm certainly not burning hundred of them. 2 at most for the entire house under fully operating fireplaces.

Lots of great info and replies, thanks for the feedback. I think I will heed the advice and call a pro to give a quote on the insert (request insulation) and wait on the downstairs until winter. I will ask them about the side cutout area in the basement though so that I can prepare myself to patch or have it patched with firebrick before the cold sets in.

I will also move up the upstairs flue to be sure I reduce chances of smoke dumping back in the house. Our house is sealed pretty well from what I can tell so I may still end up needing a fresh air intake at some point. I'd like to determine that now before its too cold but I realize the air pressure will be different in winter.
Thanks again.
Let us know how it goes with the pro.