Woodburning fireplace over full basement- Structural issue-need support?

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jasonrockhill

New Member
Jun 11, 2021
5
Nashville, TN
Hello,

I am looking to have a wood burning fireplace installed in my 1964 ranch style home over a full basement. We have always been super jealous of all our neighbors when you walk outside on a cold crisp day and you can smell the sweet smell of hardwoods burning from my neighbors chimney. So, we have decided to have one of our own installed. We will either do an Isokern Magnum 42" with Firelite stand over combustible floor (almost 2,000 pounds) or Majestic Biltmore 42" pre-fab fireplace (Around 550 pounds). The brick mason said that he typically uses around 200 bricks at 6 pounds each (1200 pounds total) for the surround. Both would have a metal chimney system that would run thru the attic and exit the roof line with a storm collar & termination cap. The living room where we would install this fireplace is directly over our laundry room in the basement. The floor joists look to be 2x10 with standard 16" spacing and the living room is about halfway thru the house. Could some of you whom had similar installations over a basement let me know what ceiling supports were needed and costs that were involved? I am hoping it is something simple that will not cost me a fortune to adequately support the weight of the fireplace/framing/drywall/brick work & chimney, because it will blow my budget and probably have to scrap the project.

Thank you in advance for the help!

Jason Rockhill
Nashville, TN
 
I strongly suggest you look into a high efficiency zero clearance fireplaces instead. They will actually heat your home rather than pull hundreds of cubic feet a minute out of the space. I’d suggest a veneer stone, no reason to add reinforcements underneath then.
 
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Or a wood burning stove.
 
We burned out fireplace in our 1965 ranch only a couple time the first year we moved in. Draft was ok but smoke still spilled out. Found out I am very sensitive to woodsmoke. Fireplace sat unused for 4 years. Then I purchased alcohol burners. That was nice but you could smell it. Installed a woodstove and now I’m very happy.
There is no way I could heat my house with the fireplace we had. It is 42” wide. Now I can keep it very comfortable with almost no smoke.

Some stoves you can burn with the door open if you use a fire screen. Consensus is that the screens never get used.

Read through the 2021 tax credit thread.
Efficient stoves (might not be any zero clearance units on the list yet) get 26% tax non refundable tax credit on the entire install.

Just some thoughts.
Evan
 
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I strongly suggest you look into a high efficiency zero clearance fireplaces instead. They will actually heat your home rather than pull hundreds of cubic feet a minute out of the space. I’d suggest a veneer stone, no reason to add reinforcements underneath then.

I am not interested in high efficiency zero clearance or wood stove. We live in Tennessee where the winters are very mild. This is more for the ambience and sights and smells.
 
What they ^ said. Less cost, faster and easier install.
You can't add that much weight to 2x10's unless bearing walls are close on both ends.
Welcome.
There's also the option of adding a load bearing wall directly below if OP goes zero clearance.

I'm old school and prefer masonry construction myself.
 
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You have designed a real problem for yourself. One possibility is you could double up, or even triple up the joists beneath the fireplace.
However, you probably have a bunch of wires and even plumbing running through those joists that would make it impossible.

You could put a load bearing wall right beneath it but probably not room with the laundry room right there.
I am at about the same latitude as Nashville, I am in the mountains in NC, and I burn my wood stove night and day about 5 months of the year.

I know you are not in the mountains but I just looked up Nashville, the average temp in January is a low of 29 and a high of 46. That is wood stove weather! You gotta get your mind right.
Get you a nice Jotul Oslo 500 like I have. Huge glass doors and the view of the fire is fantastic!
I love masonry fireplaces and I have one, that I built, pictured at left. Love to burn it. But, if anything the view of the fire in the Jotul is even better.
 
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There is no need for full brick if it is just for the look. Use a thin brick veneer to save weight. Done right, it will look like full brick while saving a lot of weight.
 
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Good idea. Use that skinny brick veneer. It is real brick just real thin, would save a bunch of weight.
Like I said, assess those joists if there are no wires or plumbing running through them, no problem to double them up. Or go wild and triple them. It would only be 4 or 5 joists.
 
Thanks, everyone for the info. Sounds like I definitely need to make sure the mason is using the lightweight veneer brick face. Also sounds like the foor joists in my laundry area (beneath where the fireplace will sit) is going to need some double or triple joist supports in that area. Is it fully necessary to get a structural engineer involved for this, and how labor intensive is this project?
 
The labor is hard to estimate. It depends on the design. Most systems like this start around $10-12,000 and go up.
I know you are not thinking about heating, but if this room is open to the rest of the house, it is worthwhile considering a modern clean-burning fireplace that can work with the door open if desired but can also heat well with the door closed. Nashville can get cold at times and it's nice to save wood and put out a lot less smoke.
 
The labor is hard to estimate. It depends on the design. Most systems like this start around $10-12,000 and go up.
I know you are not thinking about heating, but if this room is open to the rest of the house, it is worthwhile considering a modern clean-burning fireplace that can work with the door open if desired but can also heat well with the door closed. Nashville can get cold at times and it's nice to save wood and put out a lot less smoke.

Wow, that is a lot more than I want to spend. Has anyone tried the Tiger Brand Super S Series Jack Posts? Looks like you can use those permanently if they are secondary supports. Maybe place two of these to support the fireplace load? That looks to me like it would certainly work if I can make placement work in the laundry area.
 
There is a lot of labor in building a proper, chased enclosure, then finishing it with a brick veneer. Then there is the cost of the fireplace, plus chimney, top cap and wiring if it has a blower. This is why some suggested a good woodstove. That would cost a lot less to install and would not need floor bracing
 
I am not interested in high efficiency zero clearance or wood stove. We live in Tennessee where the winters are very mild. This is more for the ambience and sights and smells.
Ohh, I guess I was thrown off when you said “cold crisp days”.
 
The labor is hard to estimate. It depends on the design. Most systems like this start around $10-12,000 and go up.
I know you are not thinking about heating, but if this room is open to the rest of the house, it is worthwhile considering a modern clean-burning fireplace that can work with the door open if desired but can also heat well with the door closed. Nashville can get cold at times and it's nice to save wood and put out a lot less smoke.

Ok, I thought you were saying the flooring truss support would cost around 10k-12k. I was not prepared for that kind of cost to give the flooring system some reinforcement. My budget for the framing/fireplace install with metal chimney, storm collar, attic passthru, pipeboot/flashing and brick work/mantle is $12,000. I just need recommendations on how to support the weight of the load without blowing my budget. has anyone has had good luck using this product for secondary joist support?


Thanks!
Jason
 
Ah good, it sounds like you are on the mark. Jack posts are common for support. This is not an expensive fix. A pair of them under a carrying beam that is across the floor joist can support a lot of weight.
 
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Unless you go with the modular masonry unit, there’s no need for additional reinforcement. Unless you use traditional stone or brick of course. The BR 42 weighs around 350lbs. Tin can indeed…