What is Ondol?

As the winter in Korea is very chilly, Koreans have used a unique method of heating for centuries.

A traditional heating system 'Ondol' conducts the flue gases of a fire under the floor of a living space.

The Ondol means "warm stone". An historic ondol floor is usually made of granite blocks, about 5cm thick,

supported by columns of brick or stone. The space between the supports provides the path for the hot flue

gases. On top of the granite blocks is a clay or concrete surface for smoothness

Development of Ondol (Radiant floor heating system)

Ondol, Korean Traditional Floor heating system for houses,has undergone many changes over the years,

and has used as the radiation panel heating system for most residential buildings until now.

The biggest change to Korean ondol was the introduction of the hot water ondol system with pipes in the


The structure and heat-supply principle of the ondol system greatly changed, and comprehensive and

systematic studies have been conducted to improve the technologies related to the design,construction

and operation thereof.

Ondol, Korean traditional floor heating system for houses, has undergone many changes over the years,

and has been used as the radiation panel heating system for most residential buildings until now.

Currently most high-rise apartments has the district heating system or the local heating system using city gas,

and the heating system most widely used for houses in Korea is the hot water circulating Ondol. This is a

wet type. That is, an insulating resilient layer is installed at the bottom. After the filled layer based on

autoclaved light weight concrete is installed above the insulating layer, heating pipes are installed and

mortar is applied. Then boards, room carpets or ondol floors are laid.

Green Ondol System

Advanced technology of underfloor heating system for house which modernized

Korean Traditional Underfloor heating system

It is the standardized and scientific floor heating system. The function of Green Ondol system was proved by Korea

Institute of Construction Technology and Samsung Construction company.

Green Ondol system offers the latest energy efficient technology and environmental friendly installation.

The energy efficiency was maximized by increasing the radiation area and radiation capacity per unit area. And the

main component of this system was made of recycled polypropylene for protecting nature.

Green Ondol system makes the residential area more comfortable and environmental space.