Exposed Flue Pipe Stairwell

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ctmatt

New Member
Apr 9, 2017
2
Connecticut
We are a design/build company and working on a project in Norwalk, Connecticut.

We are looking to run exposed Class A flue pipe from an existing wood burning fireplace through the center of a stairwell up through the roof. The stair structure will be at least 6" clear from the wall of the flue pipe, but within reach to touch. We have seen exposed flue pipe in bedrooms and other occupied spaces without a chase, but would like some input on code compliance.

I have attached a rendering of the concept. Adding a chase would really close in the space and we are really hoping to come up with a solution for the exposed flue pipe. There is an existing clay liner in the masonry chimney shown which will be terminated and connected to the new flue pipe going up.

Any suggestions critiques or comments would be appreciated!

Thanks, Matt

[Hearth.com] Exposed Flue Pipe Stairwell
 
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This will probably take working with the local inspecting authority. A metal chase may be permissible, especially if it is ventilated at the top and bottom. The chase could be cylindrical as shown. Locally a friend was in a similar situation. He was permitted to create a guard out of perforated stainless steel on standoffs to protect the chimney pipe from touch. It looked and worked great.
 
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Yes like begreen said it needs some sort of chase. The ones you saw exposed in bedrooms were not code compliant.
 
What would be the issue if this was double wall insulated pipe?
 
What would be the issue if this was double wall insulated pipe?
It can still get hot enough to burn someone. And it is required by code regardless so you have to do it. The crazy thing is that it would be fine by code if you met clearances and didnt go through a floor or wall to run single wall there. But code is code snd you have to follow it.
 
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Thanks you for the input so far on this. So it sounds like if we made the case to the inspector that it is really a Cathedral space with class a double wall to meet code, and since it is within reaching distance to touch, we would also provide heat shields in those areas on standoffs or collar rings from the flue pipe.

Something like this attached.

Do you think that makes a good case for approval from the inspector?

Thanks again
 

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Thanks you for the input so far on this. So it sounds like if we made the case to the inspector that it is really a Cathedral space with class a double wall to meet code, and since it is within reaching distance to touch, we would also provide heat shields in those areas on standoffs or collar rings from the flue pipe.
I would have to check to be sure but I believe that class a chimney in the living space needs to be in a chase of some sort.
 
Ask the inspector. We've seen exposed chimney pipe in some installations here. Quite a while back someone had it run directly to their stove instead of using stovepipe. Can't find that thread right now. Another case might be where with certain cathedral support boxes the class A pipe does hang down, unchased into the room.
 
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Ask the inspector. We've seen exposed chimney pipe in some installations here. Quite a while back someone had it run directly to their stove instead of using stovepipe. Can't find that thread right now. Another case might be where with certain cathedral support boxes the class A pipe does hang down, unchased into the room.
Yes that would be the only way to know for sure what the inspector will allow. I personally don't see much of a safety issue with exposed class a in this case really but that does not mean it will pass inspection.
 
I'm guessing that the thinking may be that if the pipe is in the same room as the burning stove/fireplace, one knows the pipe will be hot. When it passes through another room or area above the fire, one does not know if it will hot or cool. Also the pipe needs protection to maintain proper clearance so that nobody puts something against it.

In the OP's customer's circumstance it seems like the main caution is to protect curious hands. The Class A will be cooler than stove pipe so it seems like a reasonable inspector would understand this.
 
I'm guessing that the thinking may be that if the pipe is in the same room as the burning stove/fireplace, one knows the pipe will be hot. When it passes through another room or area above the fire, one does not know if it will hot or cool. Also the pipe needs protection to maintain proper clearance so that nobody puts something against it.

In the OP's customer's circumstance it seems like the main caution is to protect curious hands. The Class A will be cooler than stove pipe so it seems like a reasonable inspector would understand this.
Yes i totally agree it is important in other situations to keep people from leaning things against it ect. But obviously no problem in this case.