Heat Loss Through Single Wall vs. Double Wall Stove Pipe - When Not Burning

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wjohn

Burning Hunk
Jul 27, 2021
242
KS
I installed single wall pipe when I put my stove in several years ago. My typical use case with the climate here is make a big fire in the evening to heat the house up overnight (let's say lows around 20 degrees, on average) and then during the day if it's 35 degrees or warmer, with some sun, my house will hang out at 60 degrees or so. I only load the stove in the mornings if it's going to be cloudy, colder, and/or windy. Of course we have weeks where it's colder and I burn 100% of the time, but on average that is not what I have to deal with.

I have been pondering how much heat loss I have from the house interior through the single wall pipe, and up the chimney, when I am not actively burning in the stove. Basically I have a column of cool air hanging out in the chimney separated from my house interior temp by the thin sheet of metal stove pipe, correct? And a hole in the ceiling where the heat would go up and out. I am wondering if there is a noticeable advantage to double wall stove pipe in preventing heat transfer. We always talk about keeping the flue temps up on here, but does it also reduce heat loss when not burning?

Has anyone ever had the same thought? I did some searching on here with no luck, and I doubt I am going to find any university research on this.
 
Since most modern stoves always have at least some airflow, I think most of the time there is a small active draft going up the chimney all the time. At least that’s the case for my chimney. I know my son’s is different, and he has to use a hair dryer to warm the flu — exterior masonry chimney. If yours is like mine, interior temp in the stove pipe is room temperature when the stove is out. It’s pulling room air up the chimney, so no heat transfer through the stove pipe, which would be room temp with the stove out.

If it’s a solid plug in the cold chimney, no air movement, then it’s room temperature in your interior stove pipe as well.

If it’s a negative draft, with cold air coming down the chimney, your interior stove pipe is the least of your problems I’d say.