venting wood stove pipes out a window?

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I live in a rented house which has a gas furnace. I was thinking of buying a wood stove and venting the stove pipes out a window when the power goes out. Is this safe? How could it be done safely? Has anyone tried this? Could the sparks coming out of the pipes set the house on fire? Any suggestions?

Thank you, Dawn

-- Dawn A. (dawn1@cnx.net), November 13, 1998

Answers

A bad idea. You might well set your house on fire. Flues must be carefully sited for a number of reasons. You are probably better off with a kerosene heater and a 55 gallon drum of fuel (about $75).

-- R. D..Herring (drherr@erols.com), November 13, 1998.

It is my understanding that the stove pipe must be 36" from a combustible material(that is, single walled pipe). Triple walled pipe can be installed within inches of " " . Cost of triple walled pipe is approx. $20 per ft. Sheet metal is probably the most cost effective barrier to install between single pipe and combustible mat. Approx. cost, $20 per sht.( 4'x 8') .....So..heres one suggestion; take both sashes out of window...Cut sheet metal to fit opening....Cut hole in center of sheet metal to accomadate TRIPLE WALL pipe...Put pipe thru hole and join to TRIPLE WALL "T" section outside...Use only triple wall pipe outside....install to approx. 5' above roof line...You may also get advice from your local fire dept.

-- Type r (Sortapreparin@polly.anna), November 13, 1998.

Having done this, it CAN be done. Now, there are a NUMBER of caveats here. First, the outside chimney pipe MUST extend ABOVE the roof- line of the house. The outside chimney pipe must be anchored securely a safe distance from the wall of the house (about 24 inches +/-). The pipe, as it passes through the window frame needs a fireproof, insulated pass through pipe, and the window should be replaced with sheet metal. The pipe MUST always have an upward slope from the stove to the top of the pipe. The vertical connection should be accomplished with a T (rather than an elbow) with a cap on the bottom of the T. (Picture this T laying on it's side, the long side coming from the window, the cap on the bottom, and the top going up to above the rooftop.

we supplemented the in-house heat system this way when I was in Potsdam one rather COLD winter.

chuck

-- Chuck a Night Driver (rienzoo@en.com), November 13, 1998.


As my bride just pointed out, you need to have a metal and asbestos pad UNDER the stove for floor protection, and METAL ash bucket. Please don't laugh. I truly did watch someone try to empty a fireplace ashes into a plastic pail. they said the fire had been out for the night, what can be wrong? Then the bottom fell out of the bucket onto the white carpet!! It was all I could do NOT to split a gut laughing!!!!

C

-- Chuck a Night Driver (rienzoo@en.com), November 13, 1998.


Oh my!!!! I was gonna do the wood stove thing too. I would have been the one to watch the house go up. Back to the kero heater I guess. They are on sale now at home depot. But, what about the kero fumes? Where CAn I get the drum and fuel? Thanks

-- consumer alert (private@aol.com), November 13, 1998.


And don't forget to put a spark catcher on top of the pipe.

-- Paul Davis (davisp1953@yahoo.com), November 13, 1998.

I'm just learning about this myself (please keep that in mind) so some of you more seasoned pros may want to jump in here if any this info below is wrong or needs a caveat or two (no offense taken:-). A couple things to keep in mind...

You need to learn the difference between hardwoods (oak, elm, cherry, et al.) and softwoods (pine, et al). Always burn hardwoods if possible (more BTUs, less ash and less kreosote buildup).

Just as important is learning the difference between 'green' (here not meaning 'live wood' but rather any wood having a high moisture content) and 'seasoned' wood. Seasoned wood is basically wood which has been cut to appropriate lengths (16"-20") AND split, then stacked and left to dry for a year. It's very easy to tell if it is seasoned by looking at the ends -- it will have lots of small cracks referred to as 'checking'.

If you are forced through circumstance to use softwood or unseasoned wood, clean your chimney religeously (once a week or more frequently depending upon the fuel source) to get rid of the kreosote buildup, lest a chimney fire burns your Y2K insurance to the ground.

If you go with a cast iron stove (cheaper), plan for taking it completely apart every 3-5 years to completely replace all the gaskets. You'll need tools, gasket and gasket sealant. If you go with the more expensive model (steel with fire bricks) you'll avoid this but be advised that the glass fronts on models that have them, should they be broken by accident/carelessness, are very expensive to replace. The 'ceramic glass' on one model that I've looked at was $325 just for the glass. Can't afford to keep too many replacements in stock. Heat will not break the glass but slamming the door on a chunk of wood will. The firebricks however, if broken, are cheap.

-Arnie

-- Arnie Rimmer (Arnie_Rimmer@usa.net), November 14, 1998.


check with the stove manufacturer to make sure the pipe is long enough. aside from safety, if the pipe isn't high enough, your fire won't burn properly.

-- Jocelyne Slough (jonslough@tln.net), November 14, 1998.

Arnie

Taking apart the cast Iron stove is probably not going to be needed. We have a RR Potbelly in the wife's family fishing shack which gets pretty heavy use and it hasn't been disassembled in a coon's age.

c

-- Chuck a Night Driver (rienzoo@en.com), November 14, 1998.


As I used to work for an Extension office in a conservation program, I read this thread with interest; a couple of points to add: the reason for extending the chimney three feet above the roof peak is to ensure good draft up the chimney. As for an asbestos pad and metal under the stove, I believe that what you're aiming at is something that a) won't of itself burn, and b) won't allow the floor to burn...a layer of bricks might do the trick; you could have a tray made of sheet metal to contain the bricks.

Whatever kind of stove you buy, try to get the most efficient one you can afford. Jotul, for example, makes some stoves that are fairly compact, and there are others out there of as good quality.

-- Karen Cook (browsercat@hotmail.com), November 15, 1998.



Chuck: you may well be right - I spoke to the owner of a Vermont Castings stove today (one of the better cast-iron models). He said he's had his operating several years without re-gasketing.

I guess it probably has more to do with the overall quality of the stove.

Thanks for adding that.

-Arnie

-- Arnie Rimmer (Arnie_Rimmer@usa.net), November 15, 1998.


I believe there is a rule of thumb that says the top of a chimney must be two feet above the peak of a roof *at the peak*, and it must retain a certain height as you move it any number of feet away from the peak. That is, down the roof but a horizontal distance of say 8 ft from the peak, it must still be a certain height. I believe something like that for every two horizontal feet, you can reduce the height by one foot.

Also when you are putting up anything to protect your nearby wood walls from the heat of a woodstove, be sure there is no metal conducting heat through that backing and into the wall. Not even nail heads showing towards the stove. The heat will travel down the nail and into the 2 x 4 and crystalize it to the point where it will fire up. It takes some time for this to happen, maybe months or years depending on the situation, but it can happen.

Me

-- Floyd Baker (fbaker@wzrd.com), November 15, 1998.


I think what is safe and what is legal may rather different. In the 70's I lived in a house heated by a potbelly wood stove that was vented out of a window. The kind of window that has one large upper pane, and one lower. Someone had replaced the upper pane with a sheet of metal and cut a hole for the plain old-fashioned stovepipe to pass through. No special insulations, no gasket on the stove door. A big flat stone under the stove. Period. Worked just great. (Except the couple of times I tried to burn unseasoned wood it it, and the pipe began to drip goo that caught on fire. Oops.)

-- Shivani Arjuna (odnsmall@aol.com), March 30, 1999.

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