Big Maxx horizontal flue installation

[Scott]

I have one thing left to do on my Mr. Heater Big Maxx installation, conect the flue pipe. I am planning on using a 4ft double wall horizontal vent. My question is, since I am using a double wall flue pipe, how much clearance does it need radially around it when going through the sheetrock and T-111 plywood siding? 0", 1"??

 

[W-Cummins]

I have one thing left to do on my Mr. Heater Big Maxx installation, conect the flue pipe. I am planning on using a 4ft double wall horizontal vent. My question is, since I am using a double wall flue pipe, how much clearance does it need radially around it when going through the sheetrock and T-111 plywood siding? 0", 1"??

your local code guys may have some diffrent ideas you can ask them when they come to inspect but this is what I had to do. Install a wall/celling firestop or sleeve

here is a picture of one but it's not as clear as I would have liked

 

[Scott]

Thanks for the pic. I read on a piece of double wall pipe that it should be 1" clearance for class B. I might try that.