Masonry, class a pipe or double wall pipe for garage chimney?

I've been having this debate in my head for a week now. After researching I'm still sitting here scratching my head so I figured I would post to get some feedback. My garage is a pole building style structure with pine board and batten siding with a metal roof. I recently bought a wood burning furnace to heat it and now I have to install a proper chimney that is on a budget but safe at the same time. Hard work doesn't bother me but the price of class a chimney pipe does. I've decided to try to avoid going through the roof if possible and run through the back corner wall of the garage and up. This means I need to run through the pine siding and up the wall until I get the proper height for the chimney. I know it's hard to picture this so I plan to post pictures tomorrow. What I had pictured in my mind (to keep costs down) was cutting out the pine siding roughly 4' x 4' and replacing with solid block or brick for the wall pass through. Once that was done I planned to cut a circle out and install a terracotta thimble going outside then run double wall pipe up to the proper height keeping a good 10 inches of clearance from the siding. Out the wall and up seems the best option in the back corner of my garage because there is no overhang on the the back wall because I built the garage for future expansion but that won't be happening for years. The other option is just stacking a masonry block chimney with 8" flue terracotta flue liner instead. This option does not allow me to reuse any materials though if in 5 years I decide to make the garage another 20 ft deeper. Any input is appreciated, I'm looking for any advice I can get. I'm a capable person but don't have much experience with chimney construction.

Grisu said:

Anything outside the garage must be class A chimney pipe, not double wall. The latter is only for inside. Instead of cutting a large hole in the wall and patching it up with bricks you could simply get a proper wall pass through from the manufacturer you buy the class A pipe from. That adds about $50 in cost; not enough, IMHO, to make it worthwhile to go with your plan. Anything else will be the same in both cases. A proper class A chimney is not cheap but the only way you can vent your furnace safely.

If you decide to go the masonry chimney route make sure it has enough clearance to combustibles: http://www.rumford.com/code/clearances.html Talk also to your local building inspector.

Btw. Does your local fire code and your home insurance allow the installation of a solid-fuel burning appliance in a garage? In most places that is a no-no.

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Thanks for your input. Looks like I'll be stuck searching for affordable class A pipe.
Why would it be a no no to put a solid fuel burning appliance in a garage? If a unit is safe enough inside my home why wouldn't I be able to put it in a detached garage?

Thanks for all the suggestions. I might bail on the whole thing now. At this point there is no way I could afford the class A pipe to do it. Coming into winter I get very slow at work (excavating) so I have to watch my money. I'm currently heating with master 135k torpedo heater so I'm not sure how that would be safer than a wood burner. I keep all of my gas, oil and diesel in a commercial flammable liquids cabinet that can be vented outside if need be. I'll have to talk to my insurance company to ok it with them before I make a final decision.

I did not want to go through the roof because the stove would have to sit out too far from the wall to get proper clearance. If I went out the wall it would just be a short horizontal section, 1 90 degree bend and up. It is just one of those tsc hot air furnaces that I picked up for a really low price. We already heat the house with a wood stove and I can't stand buying oil for the garage when I usually have 6-10 cords in stock at all times.

Sorry about the sideways pics and duplicates, first time posting pics on this forum. Anyway the chimney would be all the way on the right of the back of garage which would shorten the vertical distance quite a bit I would think. The wood furnace would sit pretty much where the corner of the workbench is, I can just slide the work bench to the right until clearance is acceptable.

fossil said:

Double-wall stovepipe straight up (or with a jog with 30°'s or 45°'s if needed) to a ceiling support box, through the roof, then Class A as required to daylight. Rick

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Thanks for your suggestion. I'm trying to get a material/price list together now.

begreen said:

You'll need to frame in some support for the chimney support box. And there should be no daylight showing at the gables. That is air leaking.

Here are a couple threads on the topic with pics that you may find helpful:
https://www.hearth.com/talk/threads/installed-englander-30nc.115825/
https://www.hearth.com/talk/threads/englander-30-install.115525/

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Thanks for the links. The Gable trim is my next step to close it up. I have 30 sheets of foam board to insulate too. With 3 kids it's hard to find time to work on it. I just got the back wall battens on last week.

Would this be a good start for my chimney? I noticed today that it's on sale at my local TSC and was wondering if this would be the proper setup to go through my pine sided wall. I would assume I would need a few sections of pipe also to get to the proper height for the 10/2 rule?

http://www.tractorsupply.com/en/store/duraplusreg;-chimney-steel-thru-the-wall-kit?cm_vc=-10005

Sorry, it should have come up
http://www.tractorsupply.com/en/store/duraplusreg;-chimney-steel-thru-the-wall-kit?cm_vc=-10005

Thanks, I'm picking it up in the morning then.