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Discussion Starter · #1 ·
hey all,

I am working in the basement of my cottage and would like to put in a woodstove. I am just wondering if it is possible and if it is ok to tie in the chimney pipe from that stove with the one upstairs?

The stove upstairs is a simple black pipe that goes through the roof and out. I am thinking about doing the same with the basement stove, but merging the two pipes (if it's possible)

thanks,
John
 

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No. It is against any code I've ever heard of.

Two stove (or two of any appliance) cannot use the same chimney (aka exhaust pipe).
 

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No. It is against any code I've ever heard of.

Two stove (or two of any appliance) cannot use the same chimney (aka exhaust pipe).
Code for both oil, and gas allow it.

Code allows both a gas and oil appliance to use the same chimney.

Wood, coal, your asking for trouble.

Soild fuel, use separate chimneys.
 

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It's called fire protection. If you have a single wall flue, properly assembled and surronded by air', it is considered non-combustible. If that same pipe touches ANY combustible product; wood, paper, plastic, gas, cloth, fur, etc. you won't have a cottage to work in very soon. THAT is why.
 

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may i ask why?
All pipes, stoves, or anything that carries hot gases has a clearance rating. Clearance is the minimum safe distance from combustibles. Violation of that distance means you run the risk of fire.

The clearance is usually listed in inches, varying from few to many inches. Double walled chimney pipe, wall thimbles for instance have very low clearance around 2 inches. Single wall chimney pipe has much larger clearances, and I've never seen it recommended for use when passing through a roof/ceiling or wall.

If that's your situation you need to correct it yesterday! Your local codes office should be a nice resource for doing it right.
 

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All pipes, stoves, or anything that carries hot gases has a clearance rating. Clearance is the minimum safe distance from combustibles. Violation of that distance means you run the risk of fire.

The clearance is usually listed in inches, varying from few to many inches. Double walled chimney pipe, wall thimbles for instance have very low clearance around 2 inches. Single wall chimney pipe has much larger clearances, and I've never seen it recommended for use when passing through a roof/ceiling or wall.

If that's your situation you need to correct it yesterday! Your local codes office should be a nice resource for doing it right.
Not only that but you will get more creosote build up in a single wall pipe when there is cold air around it. Also I have seen people install them the wrong way. Besides that they are thin and flimsy.

Gary
 

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Discussion Starter · #8 ·
ok, so to add a second wood burning stove I would have to run a chimney up the outside of the structure?

I am pretty sure the chimney is double walled. It goes up through the ceiling roof. the area above the woodstove is an open space/loft, about 20 feet up to the roof.
 

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ok, so to add a second wood burning stove I would have to run a chimney up the outside of the structure?
Yep, unless the original was sized for both.
I am pretty sure the chimney is double walled. It goes up through the ceiling roof. the area above the woodstove is an open space/loft, about 20 feet up to the roof.
Round here it is tripple wall:thumbsup:
 

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Double wall pipe is not legal for solid fuel (wood, coal) due to temperature and most double wall is aluminum inside pipe. Triple wall is stainless steel.
Double wall piping cannot be run up the exterior of the structure without being insulated and boxed in.
 

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Everything here is double wall
My soapstone stove was installed with 2x wall & inspected
Single pipe to the ceiling thimble, 2x after that

This is what I have seen installed, 2x wall stainless

http://www.northlineexpress.com/category/6Simpson.asp

DuraTech is a double-wall all-fuel chimney system with both U.S. and Canadian approvals for specific applications and is UL-103 HT listed
Double wall pipe is not legal for solid fuel (wood, coal) due to temperature and most double wall is aluminum inside pipe. Triple wall is stainless steel.
Double wall piping cannot be run up the exterior of the structure without being insulated and boxed in.
I've never seen 2x wall boxed in here
Plenty of installations up the outside walls
 

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I think he was thinking of B vent.

They make double stainless steel for wood stoves.

Double wall for wood stoves should be a sealed double wall, to aid in preventing creosote formation/deposits.
 

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hey all,

I am working in the basement of my cottage and would like to put in a woodstove. I am just wondering if it is possible and if it is ok to tie in the chimney pipe from that stove with the one upstairs?

The stove upstairs is a simple black pipe that goes through the roof and out. I am thinking about doing the same with the basement stove, but merging the two pipes (if it's possible)

thanks,
John


If you are going to tie these 2 together. .. the vent pipe after the tie in would have to be large enough to handle 2 stoves at the same time & handle the x tra heat


single wall vent is 6'' clearence to combustible material is not to be conceald or used in uncondition space. ie, attic crawl space etc,
 

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Discussion Starter · #14 ·
im gonna be honest, I don't know what the pipe is. Next time I am there I will find out. I know for sure that it goes through the ceiling but that's about all i know.
 

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I see it is a double insulated pipe which is OK for your application. It still requires to be boxed it per the I&O manual.

Cold Climates: In cold climates, chimneys mounted on an outside wall
should be enclosed. Exterior chases reduce condensation and creosote
formation, and enhance draft. Include an access door by the Tee Cleanout
Cap for chimney cleaning. See the detailed drawing on page 18.

See figure 23 on page 18.
http://www.northlineexpress.com/Images/Pdf/Dura-Plus-Chimney-Instructions.pdf
 

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Having plenty of wood stove experience, try not to run the chimney on the outside of the house if you can... obviously sometimes it just has to happen. Chimneys on the outside naturally flow in reverse (outside chimneys have a natural flow of cold air coming down them into the house). Trying to get a fire going with air flowing down the chimney is difficult and often very smokey. My aunt with an outside chimney used a hair dryer pointed up the flue to get things going in the right direction and then she could light a fire without smoking herself out. Some people light pieces of paper and jam it in the flue to get the flow turned around before they attempt to light a fire. It doesn't matter masonry, stainless, insulated, all outside chimneys experience this it's physics (though some suffer worse than others).

Because of the same phyics chimneys on the inside of the house always have flow in the right direction which makes starting fires easy and burning great.

Usually todays stoves don't recommend (or may not allow) single wall pipe. Often the reason is because todays stoves are so efficient they let just enough heat escape to create draft. Approx. 80% efficiency (combination of combustion efficiency & transfer efficiency) is the maximum a wood stove can be without needing a fan to supplement its exhaust. They once made an 80%+ efficient wood stove but it no longer let enough heat escape to draft. They added a fan to the exhaust but eventually canned that idea it was extremely difficult to figure out how to moderate the fan speed since burning wood is so inconsistent and their research showed no one wants to buy a wood stove you have to plug in for it to work... their claim to fame is they don't require electricity. Instead they modified it to let more heat escape and it started naturally drafting. That's why there isn't stoves over 80% total efficiency (combo of combustion & transfer) they tend to be 72-75% and why pellet stove being over 80% need a fan to exhaust (their burn is controlled so it's easy to figure out their exhaust fan speed to the rate of feed).

Anwyay, the whole point is todays stoves only let enough heat escape to draft and single-wall pipe can reduce the amount of heat escaping out the chimney below 20% and cause poor burning, draft & creosote issues.

I should also add that the warmer it is outside the lower the power of a stoves draft since it depends on temperature difference. When it's 5F outside stoves burn & draft great even single-wall ones but if you want a fire when it's 50F+ outside you need as much draft as you can muster. That's when a single-wall pipe or/and outside chimney is really gonna cause trouble and you may not be able to get a fire going. Chimney height helps with that (the taller the chimney the stronger the draft so extending your chimney may let you burn when it's 50F+ outside if you have troubles). Catalytic converter wood stoves hinder draft and usually not recommended with outside chimneys. Probably more info about wood stoves than you ever wanted to know *:eek:P
 
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