I used to own a specialty shop selling wood stoves and inserts in ’79 to ’81 and installed a couple thousand of them. Today, a lady called to ask for an estimate to put one in. This middle east situation has oilk prices going up so people are thinking that way again.
I realized driving home that a lot of things have changed since I was in the business so I need to review. Maybe there is new stuff available. Surely it’s a topic others will benefit from discussing too.
So let me tell you what I remember. You tell me where I’m wrong. I’ve got questions too, like what stove pipe is now considered acceptable for up the outside of a wood house wall. (This particular installation will be a through the wall at a gable end)
Stove must be 36″ from a combustible wall unless protected by a heat shield to satisfy local building dept rules.
Non-combustible hearth must extend 18″ to the front of the firebox openning and 12″ to either side.
Single wall stove pipe must be at least 18″ from any combustible surface unless accompanied by an appropriate heat shield.
Stove pipe connections must be secured with a minimum of three fasteners such as sheet metal screws.
Stove pipe laps should be directed so as to contain creosote drips within the pipe. (Think like a drop of tar)
Through roof and through wall connections should be designed to support weight of chimney material and be underwriter labs approved for “Zero clearance” appliocations
Zero clearance installations shall be installed with no less than 2″ clearance to combustibles.
Chimney height should be no less than 3′ above the roog ridge or no less than any point within ten feet of it.
A rain cap isn’t just for pretty.
Talk to me gang
Excellence is its own reward!
Replies
Very thorough, Piffin. I would add only . . . approved thimble or triple wall pipe where it passes through the wall. I found an old property insurance company questionnaire that calls for 6 inch legs, but zero clearance is zero clearance, right ? They also demand a U.L. or I.C.B.O. approved unit.
Anything old is new again !
Greg.
I had the same shop from '80 to '82. NFPA 211 was and still is the bible in these parts. The things you listed are the basics. Most of the changes since the early eighties concern fireplace inserts (they must be directly connected to the flue - bypassing the smoke chamber) and flue size in relation to the size of the outlet on the appliance.
Partly what I was fishing for is this,
New technology has improved plenty of stuff in our lives.
Therre are some things I knowe are new without knowing exactly what they are.
Pellet burning stoves.
More effiecient and cleaner burning coal stoves.
Stoves designed for Mobile homes and modulars are for closer to wals and they have outside air intake.
Catalytic converters are required in some places now.
It seems that I'd heard somewhere along the line of a pipe type that was less expensive for outside the wall but still insulated - just not OK for enclosed attics and in the house.
No - zero clearance never was really zero clearance any more than a two by four actually measures 2"x4" . It is nominal only..
Excellence is its own reward!
That brings up a question I've had for a long time: Anybody here ever used one of those pellet stoves? From what I've seen the pellets are proprietary. The stove is sold cheap to get you to buy the pellets.
Just as I was getting out of the business, the two big trends were the catalytics (which worked well under labratory conditions, but not in the real world and were very expensive) and the mobile home/reduced clearance units.
I was in a hearth shop earlier this week looking for a new chimney brush, and quickly browsed the stoves they had on the floor. I didn't see any catalytics. They had one mobile home unit. Most of what they carried was natural gas units that looked like woodstoves. They didn't have the right size brush, so I've got to go to a better shop. I'll ask some questions and report back.
Two things come to mind that you didn't mention.
First, check local codes. As some mentioned, they may require catalytic converters or something else kinky. You probably have already done that, but hey - You were looking for a review, right?
Second thing would be to have the HO check with their insurance company first. Some companies in Illinois will refuse coverage if you have wood heat. Others jack your rates up quite a bit. Might make a lot of difference to the HO.
I start with the premise that the function of leadership is to produce more leaders, not more followers. [Ralph Nader]
I did have a sideways reference to local codes but didn't make it obvious. That goes without saying in my mind so I forgot to actually list it. since this thread may act as a primer for newburners, it's good to bring up.
Places like Vail, Colorado do have strict controls on that sort of thing because when a temperature inversion sets into a small tight valley, it's like the smokers lounge if all the condos in town light up.
I hadn't thought about fire insurance Co. having a say. Here in Maine, burning wood is as natural as eating seafood. I do review the process and work with people to select a spot tho'
eg
A single woman with kids is not a prime candidate for a wood stove, IMHO
These gals usually run ragged trying to keep up with everything thrown their way and don't need the worry of junior burning himself or of figuring out how to run a chainsaw.
Most people who havent used wood before have no idea how much trash gets dragged in with the wood to fall on the floor, so placing it on the opposite side of a nice large room from the door, with a long stretch of white carpet in between is not the essence of wisdom.
This particular installation will run thru the gable end wall for a corner install. She wanted it run thru the other wall and asked why I wouldn't do that. "Because this is a steep metal roof and every now and then, a ton of snow will slide off it on that side. You'll be calling me down here again to replace the chimney after the snow puts it on the ground."
.
Excellence is its own reward!
Here in Georgia, with the insurance company I represent, the inspector that we send out to eye-ball the house just runs over a simple checklist on the wood burning stove. Commercially manufactured, installed by a licensed contractor (no DIY installs) stove pipe / flue meets code, just looking for proper installation. He signs off on the form, and the policy gets issued - no additional premium.
Greg.
Piff
Thanks for starting this thread. I was JUST thinking about it because when I move into my new old house on Wednesday I'd like to hook up my old Vermont Castings stove. I ran it in the house before this one I sold. Four years with no other back up system. I had it set on a circular brick platform I put together of old used brick, as well as the two walls surrounding it in the corner it was in. Heat shield behind the stove as well as the single wall black pipe up to the ceiling and the metalbestos triple wall pipe through the attic and as you said to the peak (10' away). I burnt wood but have a coal hopper I can slip in which I used mainly as it burns a whole lot longer then wood if its your primary heat source. I have all the parts ready to move to the next house and will love hearing the new fangled conections. MAINLY because its gonna go into the three car 12-14' high garage (with loft space) SHOP I will be building in the spring. Could be more dangerous in there then anywhere in the house. Something I need to be seriously aware of. Not sure its even a good idea to put one in there but there must be a way.
Be well
Namaste'
AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Notice the time stamp on the last two messages andy.
I was going to put an old stove in my shop. Lots of Maine shops do have barrel stoves and such.
I couldn't bring myself to do it tho' I love wood heat and a shop produces plenty of scrap. But it also produces plenty of dust. I've read enough stories of dust explosions to fear them. The right combination of fine dust, oxygen, and a spark can make a big old boom. It often results in death for the participant..
Excellence is its own reward!
Pretty funny Piff. I feel the same way about a wood stove in a shop although I'd think we might be able to use it under certain circumstances. Like with a sprinkler sytem above them...lol. But really, if ones careful I'd think during certain project we could fire them up as long as we take our compressor hoses and blow em off good between projects. My office will also be up in the loft area of my shop so no problem when I'm up there as long as I'm aware of dusting off the stove and pipes. I'll probably give it a shot and keep a seriously close eye the first couple of months under varies conditions.
If anyone out there has experiance with wood stoves in shops please give a shout.
Thanks and be well
Namaste
AndyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
I wasn't talking about dust on the stove, Andy. It's the fine dust in the air that causes explosions. Sure, if you have shavings up to you r ankles and drop a spark in it from the stove, Well - Darwins law will weed you out sooner or later anyway.
We should have a dust colection systen in a decent shop anyway toi keep airborne particle stoa minimum.
In the grain silos out west, dust explosions are a big thing. I heard one once. It was about twelve miles away. Out of three guys, one lived, one didn't, the other - well, they never knew for sure since he didn't come down. Honestly, they never saw any sign of him..
Excellence is its own reward!
Piff
I figured you assumed the same as I do. I'd NEVER run a wood stove when theres particles in the air. I meant, beyond THAT I'd be sure to keep the pipe and stove clean of dust. Most definatly an air filtration system no doubt. In my shop there will be three garage doors and as long as the wheather permits they'll be open with a giant fan on the opposite side blowing dust out. "Murphy's Law is the one that concerns me! Wasnt Darwin the dude with the two apples? LOL
Be well bro
Namaste'
andyIt's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Ever see a corn stove? They burn shelled corn. Corn is cheap, burns clean and hot. The stove augurs it in as needed, direct vents through the wall too. Saw them at county fairs here in midwest (corn country).
The latest stoves use what is called secondary combustion tubes instead of catalytics. Basically, stainless steel tubes across the top of the fire box (below the firebrick) have many holes, about .5" apart...and fresh air is introduced into these tubes through ductwork in the stove. The high temperatures and air cause much of the vapors to burn. There are no diminishing catalytics to replace, etc. The tubes may burn out over the years, but are relaitively simple to replace...and cheap...maybe $20 or something.
It's kinda neat to watch a modern stove burn...I just bought a Lopi Liberty for the new house. Big glass door that stays pretty clean...it really does...and the cermaic (not glass of course) is as clear as can be...so you can watch the fire. I can do this for hours it seems. Anyways, when you close down the air flow, you can see the secondary buring in the tubes...kinda looks pretty. The efficiency is way up these days...the engineering has actually done quite a bit of good.
Now, need to building this into the outdoor boilers and things will be moving right along!
Duravent is a major manufacturing of the insulated double wall chimney. Duravent Plus (I think it is) is even nicer, I believe it maybe a triple wall pipe with insulation in the inner cavity as well. Of course the insulation keeps the pipe cool, but also keeps the inner flue pipe hot to prevent creosote problems.
Also, you might want to consider supplying outside air for combustion for any new installs. Prevents the drafts and such associated with makeup air. Many stoves are plumbed for this from the factory now...a little pipe adapter to your 4" PVC or whatnot and your pulling outside air.
Basic clearances all sound right to me piffin. Have to be careful with that up the wall stuff for exterior runs...as it can lead to cool flue temps and more problems with creosote. But most importantly of course, seasoned wood.
I understand the drawbacks of exterior metal pipe but this house has some other major peculiarities. This is the only location I would install any chimney, unless, of course, she had the money for a masonry chimney, which she doesn't.
To review for others - the exhaust byproduct of burning wood includes carbon, ash, water vapour, and tars. These combine as a condensate in the chimney, generally at temperatures below about 475°F or 450°F. A masonry chimney has enough mass to retain a lot of heat, reducing the amt of creosote buildup by keeping the vapours hotter. Stove design that is intended to remove as much heat as possible before it leaves the house is efficient from an energy view but far more dangerous. Metal chimneys are of two types, both lined with stainless steel on the inside to resist the corrosive action of the stuff in the smoke. One type is the solid fill insulated with mineral fiber (Once called Metalbestos because of the asbestos fibres used in its construction.) It keeps the smoke a little warmer than the other type in the same manner as masonry, albeit with less mass. The other is called triple wall pipe, which has two chambers, about an inch wide each. the inner one, close to the smoke flue, is warmed by the smoke and the air in it rises, drawing replacement air from the outer chanber, which gets it's replacement from cold air outside so air flow is down in the outer and up in the inner. This type cools the flue smoke more so it is subject to greater condensation of creosote, IMO I have seen these virtually free of creosote in the portion that runs up through the house and suddenly becomeing full of it in the laast three or four feet outside the house envelope where temps drop to -40°F Once upon a time, these triple wall were considered safer though because there were instances of collapsed interior walls of the solid pack mostly in chimney fire situations. That risk has mostly been disolved through better design and production. Higher test temp ratings are now required also.
I think the new chimney type that is nudging my memory is one that is proprietary for connection to certain stove and fireplaces. It is a double wall similar to power vent hookups and has the cold air intake for combustion follow the outer chammber down to cool the chimney and the smoke runs up the inner flue. They work only with units designed for them, to make use of the air intake..
Excellence is its own reward!
hullo.
i installed a Scan stove last march. (contemporary scandinavian design, like a rais.) i chose it over all else partly for it's design, largely for it's smaller clearances. this stove has integrated heashields. allowing it to be 8" from the back wall, and 16" (?) or so from the sides. however, when installing in a corner, which i did, the back corners of the stove need only be 6" from the two walls, which works well in the room.
code/common sense req'd: stuff you mentioned, plus 3/4" non-combustible hearth, regular black pipe to the ceiling, double insulated pipe ($65 per36" section!) through the ceiling and from that point all the way up. tied off attic floor joists allowing 2" clearance all the way around. chimney is supported at roof with adjustable angle flashing collar/bracket rig, then it had to rise 24" above anything within 10'. wish they had told me it's good to make a chicken wire net around the rain cap to keep birds from nesting in there. got birds in the fireplace 4 days in a row before i could rig it up.
it cranks. from the minute i fire it up, the furnace stays off until about 3 hours after the fire dies out. only burns about 1-2 sixteen inch logs per hour. the re-burners really look like they're working. the glass stays clean. cost 3 grand. expensive, but you pay for what when you get, and it's a good design. coulda/shoulda spent another $500 on soapstone all the way around to disseminate the heat all night, but seemed like a lotta money for stone. maybe i'll rig up my own. gotta go stoke it, good luck.
-m
There's nothin' like a good hot stovepipe to lay your cheek on when you've been out in the wind all day!.
Excellence is its own reward!
Ahhhh, you have chosen a great subject , and its so timely . So, we have crossed paths in our history again. Permission to ramble ,... , since you have the dimensions all down. Stainless steel fiber filled installed directly over a stove containg the "S" flow has reportedly no creosote in our area providiing the wood is preheated , of proper moisture content . I brought this up , in my previous post with no hits , so I didnt go further . This is one of the greatest home comfortable values we can enjoy in appropriate climate. Since we are sitting by the fire talking anyway , let us cus and discuss it.
A room is needed to both warm and dry the wood from out side elements before being placed in the stove . Hence the example of a garage living room wall being the best place. What is known down here in the south as a moon pie and an rc cola . The ultimate place . Of course basements are good also. The best luck in a state that burns what they grow is that the wood must be properly seasoned , and of proper value to be useful. All these things mentioned supports wood heating principals.
Beach woodfires are bright and clear , if logs are kept a year . Chesnut is only good they say , till it is laid away. But ash new or ash old is fit for a queen with a crown of gold .
Birch and fir logs burn to fast , blaze up bright , and do not last. It is said by the Irish said, hawthorn bakes the sweetest bread .Elm wood burns like churchyard mold , even the very flames are cold . But, ash green or ash brown is fit for a queen with a golden crown.
Popular gives a bitter smoke, fills your eyes and makes you choke. Applewood will scent your room , with an incense like perfume . Oaken logs , if dry and old , do the best job on old man winters cold . But ash wet or ash dry , a king may warm his slippers by.
Ash has the lowest content of moisture green , but Live oak is the heaviest hardwood king , followed by hickory. If you didnt have a lot of time to cut for the queen , ash would do, but if you had done your work well in advance oak and hickory housed at least one year dry would be the choice for those all night burns with low temps out side.
Tim Mooney
I installed a Lopi Liberty three years ago with Metalbestos pipe. We selected it because it didn't have a catalytic afterburner. The catalytic systems have to burn fully dried hardwoods, to fussy for me. In northern Michigan I wait for the utilities to come through and do their clearing, they cut everything to 8 foot, I just come behind with a trailer. We use it as a primary heat source in a 2000+ sq. ft. A frame cottage with little or no insulation. Sizing is real important, the Liberty puts out so much heat even shut down it's hard to use on mild days. The Liberty only requires 10" to back wall if you use a double wall pipe or 16" if you use a single wall and 16" from the side. I think the real trick is to avoid horizontal runs at all costs. If you need to go through a wall use 45's instead. Soot and creasote builds up on the horizontal areas and causes chimney fires. The stove I replaced had a small horizontal section that had flamed up and charred the surrounding structure. I checked with my insurance agent on any premium increases on adding a wood stove and AAA said no.
Hey Master, Do you like the Liberty? Just bought one...can't wait to get her in and fired up.
Has everything held up well over the past 3 years? Glass stay clean?
I love it, but it's like I said, it kicks out a lot of heat even with the air shut down. We burn everything green, wet, rotten and otherwise. I was just up at the cottage, the outside temp ranged from high 20's at night to high 40's during the day. We had to be careful not to get the place above 70. I would burn large logs at night and during the day when we were out. This place is on a slab and has little or no insulation and is 2000+ sq. ft. The Liberty could blast us out with no problem. The only time the glass smokes up is if we are burning something a little green or wet at night when I have the air shut down, but as soon as I open it up in the morning it cleans itself.
Thanks master. I am building a very open 2800 sq ft place...gambrel roof...25' peaks...3 ceiling fans.
I think the libery will keep us warm! Sounds great...can't wait to watch the snow fall on the spruces surrounding the house as I gaze into the fire...
I am a little worried about controlling my radiant heat system with the Liberty blasting away as well. I must say, the folks over at heatinghelp.com on the wall are great guys...I have learned much...and I think it is now under control (Tekmar 363 controller fits the bill). Sorry for the aside...