Comments by "" (@manofsan) on "Essential Craftsman" channel.

@essentialcraftsman - would be interested in seeing your observations on the traditional heating system used in Korean homes, which is called "Ondol". It's got an external facing fireplace/hearth built into the exterior base/foundation of the home, and a flue leading under the main floor which channels hot gases underneath the floor to heat it, ultimately reaching a vertical flue on the other side. There are videos of this setup on youtube, and I found the concept fascinating, as it's a very ancient system.
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