What is Ondol?
1.
The traditional floor heating system in Korea. Gravel or water-pipiping beneath the stone board floor. The fire in the kitchen can be used for both cooking and heating up the floor. Heat energy gets trapped under the floor that it can warm up the room with very little amount of fuel.
Ondol is an ancient technology, yet it still remains as the most energy-effective heating system in the winter time.
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