Basic Question on how much space three flues will take

[peakbagger]

I am slowly designing a future house, whether its get built is another story. One detail is what is the minimum size pipe chase for three 6" flues?. What sets the minimum spacing of the outer wall between various prefab systems, is it the pass through the ceilings or is there a hard and fast minimum air gap between adjacent outer walls? Since its a clean sheet design I want to minimize the size of the chase. I think the optimum would be three six inch flues in a triangular pattern with a minimum clearance between each pipe and the exterior of the chase. It will be tall chase, my guess from the basement floor to the flue outlet adjacent to the ridgepole will be 32' with the Jotul's one floor up from the basement. The Jotuls will be on wide hearth next to each other (one of them is a 404 cookstove).

The other issue is durability. Is there any prefab system with the longest durability I should design around? The primary flue will be a Tarn boiler, with a couple of small jotuls (that are actually setup for 5" pipe but I figured I would standardize at 6".)

 

[gthomas785]

I assume you are talking about some kind of double wall class A chimney pipe. I don't know the answer to your question but think about how the pipes will terminate above the roof, you don't want them too close together both because of interference with each other's draft and also the size of caps you will need for each one.

 

[Bad LP]

I assume you are talking about some kind of double wall class A chimney pipe. I don't know the answer to your question but think about how the pipes will terminate above the roof, you don't want them too close together both because of interference with each other's draft and also the size of caps you will need for each one.

I've seen this flue issue mentioned a few times. In my own case all three flues exit at the same elevation in a space 32X36. No issues to date but I just had a full cap installed. Only ran the insert last weekend so I don't know more at this time.

 

[bholler]

I would leave 4" in-between each of the flues. 2" on either side. So 24 for the 3 chimneys themselves and another 12" for spacing.

As far as brands excell ventis or jerimiahs would be my choice.

 

[brenndatomu]

I would leave 4" in-between each of the flues. 2" on either side. So 24 for the 3 chimneys themselves and another 12" for spacing.

Curious why this is...for future service accessibility? Obviously not for CTC...

 

[bholler]

Curious why this is...for future service accessibility? Obviously not for CTC...

So you can use all of the stock supports firestops etc without interfering with each other. As well as allowing room at the top for caps etc. If you want to allow service later you need to allow room for a person to get down inside next to the chimneys

 

[brenndatomu]

So you can use all of the stock supports firestops etc without interfering with each other. As well as allowing room at the top for caps etc. If you want to allow service later you need to allow room for a person to get down inside next to the chimneys

There it is...makes perfect sense.

 

[Jay106n]

Just for reference, I have three standard rectangular 12”x8” clay flues. My total chimney foot print is 64”x32”.

 

[bholler]

Just for reference, I have three standard rectangular 12”x8” clay flues. My total chimney foot print is 64”x32”.

He is asking about chase size for 3 6" prefab chimneys.