Ancient Korean Heating System Still Warms Homes Today
While heating in many parts of the world is mainly associated with radiators, stoves, fireplaces, and warm air from air conditioners flowing through a room, in South Korea, centuries ago, they knew how to heat an entire room without a stove in it. While the outside temperature dropped to minus 20 degrees, stone floors were so warm that it was pleasant to sit on them. The secret lay beneath the floor, in a system called ondol (“on-dohl”, which literally translates to “warm stone”).
TL;DR
- Ondol is an ancient Korean underfloor heating system that uses smoke from fires to warm stone floors.
- The fire is lit outside the room, and hot smoke travels through channels under the floor, heating stone slabs.
- This system allowed traditional Korean homes to remain warm even after the fire was extinguished, crucial for a culture where people lived and slept on the floor.
- The design of the ondol channels was carefully engineered to maximize heat transfer and efficiency.
- The ondol system dates back at least 1,600 years and has been a significant part of Korean housing culture.
- Modern ondol systems have evolved, replacing smoke channels with hot water pipes, making them adaptable for multi-story buildings.
- Similar underfloor heating concepts existed in ancient China (kang), Rome (hypocaust), and Spain (gloria castellana).
- The Korean government plans to designate ondol as a national intangible cultural asset.