Started my austral install

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KindredSpiritzz

Minister of Fire
Oct 31, 2013
798
appleton, wi
and already I need advice. i want to stick the stove in this corner and build a shield so i can tuck it in there closer to the walls. I have a warm air vent (black flex piping) going into the back bedroom right where i envisioned the chimney pipe going up thru the roof. Theres also a cold air return pipe (silver) in the wall there that is galvanized.
If i run the chimney thru there how far away does the ceiling box have to be from that galvanized cold air return piping in the ceilng/attic area? It's be about a foot away im thinking. I plan on moving the warm air vent so that won't be an issue. I'd like the chimney to go thru the roof as i think it would look nicer and work better but maybe i'd be wise to go thru the wall instead? I'd like the stove to sit in the corner so i think it'd look funny with the pipe going sideways out the wall to the right.

ok so this is what i had in there, a fake electric fireplace that i just ripped out this past weekend.
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and this is whats behind it. the cold air return pipe is in the ceiling just above the light and then comes down the wall into the other room.

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and heres an outside view. The chimney would come out between the windows where im missing that little chunk of siding, either thru the roof or thru the wall.

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So my questions are. How close can the chimney box be to the galvanized cold air return piping. Should i go straight up thru the roof or take the easier route thru the wall? Any advice or words of wisdom would be appreciated.
 
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If you have room to run mount your ceiling support box directly above your stove, do it. As long as you don't have to cut into the cold-air return duct, I wouldn't worry about how close it is. You're going to have a minimal amount of chimney as it is, so you might as well make it a straight run. You stove will draft better. Most stove manufacturers call for at LEAST 14 feet from the hearth pad to the cap, & you will probably have to have HALF of that in Class A above the roof. HTH...
 
12 ft is the minimum chimney height for this stove. I'll make it as high above 12 ft as is feasible. What sucks is i have to ripe a good chunk of the ceiling down to work and theres only about a foot of attic space above the ceiling to work in. Worst case, i have to rip the cold air return out completely for that back room but im hoping i can miss it with the chimney or reroute it a bit. Whoever built that add on room should be slapped for how he did it.
 
Looks like a gnarly location. The proximity of the duct to the support box is not an issue. Ceiling support boxes have the 2" clearance to combustibles built in. But you will need to have at least 6" of double-wall connector clearance to combustibles below the support box.
 
But you will need to have at least 6" of double-wall connector clearance to combustibles below the support box.

not sure i understand. The support box will come thru the ceiling and from the stove to the support box the double wall stove pipe has to be at least 6 inches from the walls??
 
That's correct. 6" is the minimum clearance for double-wall pipe to the nearest combustible, in this case the walls. Your stove clearance requirements take this into account by providing separate clearance requirements for single or double wall connector pipe. The stove clearance will be different depending on whether the stove is installed parallel or diagonal (corner install) to the walls.

What are you planning to do with the large plastic flex duct?
 
stove pipe shouldnt be a problem as the stove has to be 16 inches from combustibles or 8 inches with wall shielding. Im going to put it at 10 inches just to be safe.
The flex piping i'll move back into the room more so its out of the way and reroute it back into the other room and install a new vent for it. Looks like the galvanized cold air return piping should be out of the way enough as to not interfere with the chimney. For some odd reason i have two cold air returns for that room 3 ft apart along that wall.
 
stove pipe shouldnt be a problem as the stove has to be 16 inches from combustibles or 8 inches with wall shielding. Im going to put it at 10 inches just to be safe.
Are you referring to "C" clearance in the OM for corner install? If so the 50% reduction that they show in the table for "wall sheild" can only be reduced to a min. of 12" not any closer according to NFPA 211. They don't seem to include that stipulation in the OM. Unless there is some other local code you are going off. Just wanted to throw that out there before you get too far along.
begreen- I'm not missing something else am I?
 
yes, that is what im referring to. This whole OM is hard to follow. On page 11 It says the clearance for single wall pipe is 16 inches and below it double wall is 17 inches. which makes no sense to me. Why would double wall be farther away? Page 14 says you can reduce clearances with shielding, brick or ceramic tile spaced out 1 inch by 50%. I admit i suck at math but isnt 50% of 16 inches 8 inches?? And why put that in there if its not applicable because of NFPA 211??
This is turning into a headache and i barely just begun.
Anyways, appreciate the heads up as i'd rather not have any surprises later after im "done"
 
That wall to the right under the dry wall is all cement block. Would i have any clearance issues if i ripped that dry wall off and stuck it along that wall?? Couldnt i have it 6 inches away from that wall as long as nothing combustible was within 16 inches of the stove anywhere around it? Just looking for different options.
 
yes, that is what im referring to. This whole OM is hard to follow. On page 11 It says the clearance for single wall pipe is 16 inches and below it double wall is 17 inches. which makes no sense to me. Why would double wall be farther away? Page 14 says you can reduce clearances with shielding, brick or ceramic tile spaced out 1 inch by 50%.
Anyways, appreciate the heads up as i'd rather not have any surprises later after im "done"

The reduction of clearances to combustables chart they show in the OM is odd. Usually 4"brick with a 1" Ventilation space is a 66% reduction by NFPA 211. they show a 50%, and they show other ways to reduce by 67%.As well as the larger clearances when using double wall pipe for both the C and F distances. When going off codes the OM usually prevails, but your local inspector really has final say (your insurance company will also like insurances). If it were me I'd want to get clarification for sure by by local building inspector. You can view the NFPA 211 online free at www.nfpa.org ,I'd take a copy of that with the owners manual to him/her and ask him/her for a decision. Is it required to get a permit for the installation in your town? Either way to prevent having to re install because the inspector/insurance company have a problem you should IMO get it clarified. You can always just go off the further of the variances to be safe as well. Have you called SBI and ask them if those reductions are correct? But as far as the 12" that is the code according to NFPA 211 12.6.2.1.2
"Unless the appliance is specifically listed for lesser clearance, the clearance after reduction shall be not less then the following:
12 inches to combustable wall
18 inches to combustable ceilings"
and that is to the combustable wall not the brick itself so

That wall to the right under the dry wall is all cement block. Would i have any clearance issues if i ripped that dry wall off and stuck it along that wall?? Couldnt i have it 6 inches away from that wall as long as nothing combustible was within 16 inches of the stove anywhere around it? Just looking for different options.

Yes you would measure from the stove to the combustable ....cement block is a non combustable.
 
Sometimes when a stove is tested they find that the clearances go up with double-wall pipe. That is the stove ran a bit hotter and thus the increased clearance requirement. This is less common with stoves that have side and rear shields built in like the Baltic. In this case the final say on clearance reduction should be with the inspecting authority. If they go by the manual then you should be able to reduce clearances. A pure cement block wall is non-combustible and will not need shielding to reduce clearances. Sketch out a top down view for the inspector that illustrates your plan and get it approved in advance to avoid later surprises.

What is on the other side of the cement block? If it is outdoors you probably want to insulate it or it will be a perpetual source of serious heat loss.
 
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Sometimes when a stove is tested they find that the clearances go up with double-wall pipe. That is the stove ran a bit hotter and thus the increased clearance requirement.
BG-That is understandable and I agree but what makes the 24 gauge sheet metal with 1" ventilation a 67% reduction and not a 66%? you don't think that could be a misprint do you? and why only a 50% reduction in using a masonary wall with the 1" vent because it tested hotter with a brick wall? And do you think the 12" rule wouldn't apply to that brand stove for some reason? I defer to you BG as you work with other brands more often I was just wondering for myself. I know in the end the AHJ has final say I was just curious in case I run into this myself. Thanks BG
 
Manuals sometimes seem like a bewildering assemblage of boilerplate facts and legal docs. I haven't delved deeply into the anomalies in Drolet's manuals, but this could just be a case of poor documentation.
 
when i measure rear clearances do i measure off the rear heat shield or the stove body itself ?? And do i have to account for the rear blower assembly in clearances??
Im thinking i have to measure from the heat shield and yes on blower assembly but just want to make sure.
 
Clearances are measured from the outer most surface of the combustable to closest point on the stove. You are doing a corner install so from the closest edge on the corner of the stove to the 1st point of a combustable material.
 
Well i got the wall shield done. The stove will be more than 16 inches from the wall so the shield is more for peace of mind than clearance concerns. It rises above the top of the stove by 20 inches like its supposed to. Not sure on the side clearance where its supposed to be 18 inches past stove on the sides but its a moot point since its 16+ inches away from the wall. Im going to put stone tiles on the shield, not sure yet what way i'll go on the top dry wall. May tile it or paint it.

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I mortared the stone tiles on the cement floor. First time i ever worked with stone tiles so it didnt come out the greatest but im not picky. Not sure what im gonna do with the sides yet, need to fill in that one inch gap, probably use some type darker stone tile to accent the edges and use bull nose along the top edges and i have to grout yet.
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Attic insulation shield was a pain til i figured out it had to sit on TOP of the support box. Next up is cutting a hole in the roof and running the insulated stainless pipe down and doing the flashing and all that jazz. Im assuming i have to cut the hole the same size as the support box ? Once i get that done it should be all downhill from there hopefully.
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Whoa, get the installation instructions for this chimney pipe before proceeding. That does not look like a typical ceiling support box, but it may be the camera angle? It almost looks like the roof flashing is installed in the ceiling. Again, this could just be the camera angle so my apologies in advance if this is the issue.
 
its the attic insulation shield which sits on top of the 2x4 support frame i built. I havent cut the hole or did anything with the roof yet. I been following the instructions, altho some sections aren't as clear as i'd like. The insulated stainless pipe drops right down thru there and connects to the stove pipe adapter and ceiling support box once i get to that point. I think im ok but im not positive about anything.
 
OK, that makes sense. Looking at it from that angle without the support box is an unusual view. After you explained it now it makes visual sense.
 
Im happy to have your eyeballs checking things out cause i'll admit this is the first time experience for me. I will end up pulling a permit and having it inspected for peace of mind but hopefully this is one of the few things in my life I can do right the first time around.
 
Today i cut the whole in the roof to start the chimney process. Of course 5 minutes after i took this picture it started raining. Thankfully it didnt last real long. So this is the top of the attic insulation shield.
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Got the flashing on, sealed and nailed down. Shoot, reminds me i forgot to seal the nail heads with silicon.
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The i got the pipe in and put the storm guard on. Had a hell of a time figuring out that storm guard, the tab and long screw didnt make sense so i just drill it thru and bolted it and sealed the inside edge
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And theres the finished product. Anyone see any issues or problems??
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Next up finishing the inside
 
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Maybe it's just me . . . but I think I would want a support or two attached to the chimney for more support on those windy days.
 
I'm a bit concerned about the flashing because of the flat roof. Was there a bead of silicone or roofing tar run around the underside perimeter before nailing it down? The nail heads should get a dab of silicone and so should the circumference of the storm collar where it meets the stove pipe.
 
yes, I plan on adding a support to the chimney just to be safe, it's 5 ft tall so i don't think I really need one tho.
And yes i ran 2 beads of silicon around the flashing and another bead around the edge and did the storm collar as well. I just forgot to do the nail heads.
Im really trying to do this job right so im leaning towards doing more than whats necessary.
 
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