How to fix draw issues - is it this exposed non-insulated chimney?

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SmokingPriapist

New Member
Jan 9, 2023
5
USA
I bought a home with two wood fireplaces, and realized pretty quickly they are almost unusable with smoke filling my house. After a bit of research, I think the main issue is the chimney pipes they used:

chimney1.jpg

The middle chimney is the main floor fireplace, located one floor down. It's a straight shot to the fireplace below.

So far, I've tried making the fireplace opening (51" x 24") slightly smaller. This seems to have helped quite a bit, but I'm thinking the main issue is the chimney pipe being non-insulated (it's very hot to the touch with a fire going).

Am I on the right track here? Could I replace that stack with an insulated chimney pipe like DuraVent to help with the smoke draw?
 
I bought a home with two wood fireplaces, and realized pretty quickly they are almost unusable with smoke filling my house. After a bit of research, I think the main issue is the chimney pipes they used:

View attachment 307331

The middle chimney is the main floor fireplace, located one floor down. It's a straight shot to the fireplace below.

So far, I've tried making the fireplace opening (51" x 24") slightly smaller. This seems to have helped quite a bit, but I'm thinking the main issue is the chimney pipe being non-insulated (it's very hot to the touch with a fire going).

Am I on the right track here? Could I replace that stack with an insulated chimney pipe like DuraVent to help with the smoke draw?
Those pipes are also way too small to work with an open fireplace
 
Are these for masonry flues with these metal chimney adaptations or ZC prefab fireplaces?
 
Are these for masonry flues with these metal chimney adaptations or ZC prefab fireplaces?
I think they are masonry flues - have a fire going and can't look at the moment, but the new exposed chimneys were done in a remodel before I bought it.
 
If so, they look choked down about 2/3ds. What were they thinking?
 
If so, they look choked down about 2/3ds. What were they thinking?
I looked up the basement flue - the fireplace is brick, the damper is rectangular, but above that it looks like a round pipe all the way to the top (same diameter from all the way up from the damper)
 
I looked up the basement flue - the fireplace is brick, the damper is rectangular, but above that it looks like a round pipe all the way to the top (same diameter from all the way up from the damper)
I wonder if they liner the whole thing with an undersized liner
 
If the metal pipe is 8" it is most likely a double wall pipe. It looks like a duravent type system with the caps fitting well in other words not a hack job.
I think the clay pipe is 12" but could be wrong but that would make sense of how it appears in comparison to the 8" metal pipe.
 
If the metal pipe is 8" it is most likely a double wall pipe. It looks like a duravent type system with the caps fitting well in other words not a hack job.
I think the clay pipe is 12" but could be wrong but that would make sense of how it appears in comparison to the 8" metal pipe.
It looks like single wall to me but regardless they aren't large enough for an open fireplace so definitely a hack job
 
I took a few more photos to help clarify:

Fireplace_1.jpgFireplace_2.jpgFireplace_3.jpgFireplace_4.jpg

I'm thinking I'll raise the grate with some bricks, and make a smoke guard with a piece of 3-4" wide steel up top to see if that helps. The soot on the fireplace is from my aluminum foil experiment (that did seem to work).
 
I took a few more photos to help clarify:

View attachment 307935View attachment 307936

View attachment 307939
View attachment 307940

I'm thinking I'll raise the grate with some bricks, and make a smoke guard with a piece of 3-4" wide steel up top to see if that helps. The soot on the fireplace is from my aluminum foil experiment (that did seem to work).
You really need properly sized flues for your fireplaces. That looks like a pretty large firebox i really don't ever see it working with that small flue
 
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The clay tile before the silly metal chimney top looks like maybe 10" x 12"? If so, using the 10 to 1 ratio, that would support a 1200 sq. in. fireplace opening, or 30" x 40".
The 8" round flue is about 50 sq. in. in area, times 10 = 500 sq in or about a 20" x 25" fireplace opening.
 
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