Heating the floor below the wood stove

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DaveInPA

New Member
Sep 4, 2020
3
Bucks county PA
I am installing a new wood stove on my newly finished second floor of my old barn. It’s plenty big for the 700sq-ft space (jotul f55) that will have plenty of closed cell insulation. Thing is my workshop is below on the ground floor and thats staying unfinished. I’m thinking about putting a 6” duct between the floor located near the stove. I figure if i put a fan in that duct to pull hot air from the warm upstairs to the cold downstairs it will maybe help add A little heat to the shop.

Is this not going to work and I’m wasting time and potentially upstairs heat? I can always try it and then fill the duct with insulation and close it off later too.
 
Can you put the stove in the workshop? Heat doesn't like to go down and also you'd get a longer chimney/keep the wood mess in the uninished part.
 
I am installing a new wood stove on my newly finished second floor of my old barn. It’s plenty big for the 700sq-ft space (jotul f55) that will have plenty of closed cell insulation. Thing is my workshop is below on the ground floor and thats staying unfinished. I’m thinking about putting a 6” duct between the floor located near the stove. I figure if i put a fan in that duct to pull hot air from the warm upstairs to the cold downstairs it will maybe help add A little heat to the shop.

Is this not going to work and I’m wasting time and potentially upstairs heat? I can always try it and then fill the duct with insulation and close it off later too.

Yes, it's not going to have a significant effect downstairs; the heat will stay near the ceiling, and even if you would add a ceiling fan in the shop to mix the air, the heat will drain through the noninsulated walls. So the little (if any) heat you'll get downstairs will simply heat the great outdoors.
 
not to mention you're introducing an avenue for cold air to seep up to the ground floor from the basement when the stoves not on or has died down.
 
Btu/hr = CFM * 1.08 * tRise
Air temp coming from the stove area = 80deg
Temp downstairs = 68deg
6" round duct typically handles around 100cfm

100cfm =BTU/(1.08 x (80-65))
BTU = 1620btu, or 475Watts

It may help some. 475watts for 700sqft is tiny though. And not nearly enough if the place down there is unfinished/uninsulated, or with cement walls. An electric heater on low, at 900watts, would cost about 22cents an hour, be convenient, quite, with nothing to install, and would be twice the heat, but still probably wouldn't heat the place to 68. With the midwest climate currently at below zero for the past 2 weeks, far more than 1620btu/475watts would be needed any way you look at it..
 
Btu/hr = CFM * 1.08 * tRise
Air temp coming from the stove area = 80deg
Temp downstairs = 68deg
6" round duct typically handles around 100cfm

100cfm =BTU/(1.08 x (80-65))
BTU = 1620btu, or 475Watts

It may help some. 475watts for 700sqft is tiny though. And not nearly enough if the place down there is unfinished/uninsulated, or with cement walls. An electric heater on low, at 900watts, would cost about 22cents an hour, be convenient, quite, with nothing to install, and would be twice the heat, but still probably wouldn't heat the place to 68. With the midwest climate currently at below zero for the past 2 weeks, far more than 1620btu/475watts would be needed any way you look at it..

Thats helpful to think about it that way. The shop area is actually only 400 sq-ft so thats a bit better. I do have an electric heater in there and on cold days it doesn't do much. Really i just need it in the 40s/50s to be comfortable on days when its 20s outside.
 
IMO if you need to move heat you need to do it with water,. My friend has done it for 20 years with a Fisher Clone with home made heat exchanger and hydronic piping. He even has a fan forced unit heater for a heat dump. His backup is electric heat and it rarely goes on
 
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IMO if you need to move heat you need to do it with water,. My friend has done it for 20 years with a Fisher Clone with home made heat exchanger and hydronic piping. He even has a fan forced unit heater for a heat dump. His backup is electric heat and it rarely goes on
I'd like to see pics of this system. Curious.
 
Heat to go down, and cold to go up, is not normal convection. Even with stoves in the basement heat won't rise well, with out pushing cold air down.
 
Throw a small rocket stove heater in the garage, a nice one cost about a grand, or you can make one very inexpensively..
 
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