Furnace in attached garage?

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

tjcole50

Minister of Fire
Oct 5, 2013
509
Ohio
had a thought, may be stupid. But has anyone put an add on furnace in an attached garage and say ran your ducts up above the ceiling of the home and then dumped them down into the house? We have a new home being built. This thohght randomly came to mind. The one issue i see is not getting a proper return air and pulling it from the garage with a filter box. Would offer heat to the garage and home which would be nice. Yes insurance is fine with wood burning appliance in the garage sounds crazy but they do not care. They claim todays stoves are safe enough now... which is great hearing from an insurance company. Anyway fire away
 
Neighbor down the road did this, but his house was a split level. His supply and return lined up pretty well. If memory serves me correct he had to 90*down 6" then 90* horizontal his hot air to get it to line up with existing duct work.

Sent from my SM-G950U using Tapatalk
 
I expect it would be fine if you permanently sealed off the garage doors so the garage could not be used as a garage. Otherwise its a perfect way to fill the house with carbon monoxide. Plus would increase the chance of fire in the garage spreading into the home.
 
Air is not a good medium for transferring heat for long distances.
 
  • Like
Reactions: mike van
I have a friend who did this and he is happy with it and I think it works fairly well. It was a retrofit though, and the home is a mini and garage was new so his home doesn't take a whole lot to heat. But new construction has so many opportunities to do things differently, easily & 'right' from the get go that I don't think I would consider it building new, mostly for reasons already mentioned.

EDIT: Also going up then down with a supply run off a furnace is usually not the best idea - potential for bad things to happen if the power goes out when burning.
 
Last edited:
i would be reading the fine print real close on that. Local code around my parts require minimum 4ft above floor level for any heating appliance in a shop or garage. ( could even be national code)
 
I would really question the person you talked to at the Ins Co...I bet they don't know what they are talking about, I bet company policy says otherwise on this...pretty rare that wood burners are allowed in the garage unless sealed off separately. Might wanna check with local building code too.
Also, ductwork going up into an attic area and then down again usually doesn't work out too well for wood burners...can be a lot of heat loss in the attic, and if the power goes out it becomes a heat trap...wood heaters need to be able to be cooled by gravity air flow if needed.
I just bought a wood furnace from a guy that had this setup...he said it worked OK...but then he got rid of it...so how well did it work really?
If I were building new, I would design the house around the wood burner of choice...not "retro-fit it in there"
In the case of a hot air wood furnace, put it toward the middle of the basement, then build a "bump out" area into the foundation covered by a Bilco door...open doors, dump wood pile in, close doors, done.
 
wood burner furnace in basement- code says 2" clearance to combustables on first 10 ft of duct run-there after 1" when using solid fueled appliance, most homes with a conventional heat furnace oil or gas are not constructed this way. this being for forced hot air of course running a heat exchanger off a wood boiler in basement not sure.
 
  • Like
Reactions: brenndatomu
why not use radiant hydro floor heat if you are building from new? I am putting my wood boiler in my garage since I only have one flue in the basement and i'll have a nice heated garage all winter. water is way easier to move around and heat with.
 
why not use radiant hydro floor heat if you are building from new? I am putting my wood boiler in my garage since I only have one flue in the basement and i'll have a nice heated garage all winter. water is way easier to move around and heat with.

One reason might be the insanely expensive equipment required. EPA furnace is maybe 1500$. Gasser boiler, pumps, storage, manifolds, expansion tanks, etc. will be approaching 15000$!!!!
 
yep if don't want something around either tax it to death or regulate it into a black hole. Hot water systems were insane enough price wise before the current Epa regulations ( Those prior units were exempt from stove regs )