Question: What were heated floors in ancient buildings called?
About the article "South Korea", section "Architecture".

Candidate passages:
Because of South Korea's tumultuous history, construction and destruction has been repeated endlessly, resulting in an interesting melange of architectural styles and designs.
Korean traditional architecture is characterized by its harmony with nature.
Ancient architects adopted the bracket system characterized by thatched roofs and heated floors called "ondol".
People of the upper classes built bigger houses with elegantly curved tiled roofs with lifting eaves.
Traditional architecture can be seen in the palaces and temples, preserved old houses called "hanok", and special sites like Hahoe Folk Village, Yangdong Village of Gyeongju and Korean Folk Village.
Traditional architecture may also be seen at the nine UNESCO World Heritage Sites in South Korea.
Western architecture was first introduced to Korea at the end of the 19th century.
Churches, offices for foreign legislation, schools and university buildings were built in new styles.
With the annexation of Korea by Japan in 1910 the colonial regime intervened in Korea's architectural heritage, and Japanese-style modern architecture was imposed.
The anti-Japanese sentiment, and the Korean War, led to the destruction of most buildings constructed during that time.
Korean architecture entered a new phase of development during the post-Korean War reconstruction, incorporating modern architectural trends and styles.
Stimulated by the economic growth in the 1970s and 1980s, active redevelopment saw new horizons in architectural design.
In the aftermath of the 1988 Seoul Olympics, South Korea has witnessed a wide variation of styles in its architectural landscape due, in large part, to the opening up of the market to foreign architects.
Contemporary architectural efforts have been constantly trying to balance the traditional philosophy of "harmony with nature" and the fast-paced urbanization that the country has been going through in recent years.
In ancient Rome, the insulae (singular "insula") were large apartment buildings where the lower and middle classes of Romans (the plebs) dwelled.
The floor at ground level was used for tabernas, shops and businesses with living space on the higher floors.
Ancient Roman insulae in Rome and other imperial cities reached up to 10 and more stories, some with more than 200 stairs.
Several emperors, beginning with Augustus (r. 30 BC-14 AD), attempted to establish limits of 20–25 m for multi-storey buildings, but met with only limited success.
The lower floors were typically occupied by either shops or wealthy families, while the upper stories were rented out to the lower classes.
Surviving Oxyrhynchus Papyri indicate that seven-story buildings even existed in provincial towns, such as in 3rd century Hermopolis in Roman Egypt. 
Ancient shrines were constructed according to the style of dwellings (Izumo Taisha) or storehouses (Ise Grand Shrine).
The buildings had gabled roofs, raised floors, plank walls, and were thatched with reed or covered with hinoki cypress bark.
Such early shrines did not include a space for worship.
Three important forms of ancient shrine architectural styles exist: "taisha-zukuri", "shinmei-zukuri" and "sumiyoshi-zukuri".
They are exemplified by Izumo Taisha, Nishina Shinmei Shrine and Sumiyoshi Taisha respectively and date to before 552.
According to the tradition of ", the buildings or shrines were faithfully rebuilt at regular intervals adhering to the original design.
In this manner, ancient styles have been replicated through the centuries to the present day. 
Ancient shrines were constructed according to the style of dwellings (Izumo Taisha) or storehouses (Ise Grand Shrine).
The buildings had gabled roofs, raised floors, plank walls, and were thatched with reed or covered with hinoki cypress bark.
Such early shrines did not include a space for worship.
Three important forms of ancient shrine architectural styles exist: "taisha-zukuri", "shinmei-zukuri" and "sumiyoshi-zukuri" They are exemplified by Izumo Taisha, Nishina Shinmei Shrine and Sumiyoshi Taisha respectively and date to before 552.
According to the tradition of ", the buildings or shrines were faithfully rebuilt at regular intervals adhering to the original design.
In this manner, ancient styles have been replicated through the centuries to the present day. 
Ancient shrines were constructed according to the style of dwellings (Izumo Taisha) or storehouses (Ise Grand Shrine).
The buildings had gabled roofs, raised floors, plank walls, and were thatched with reed or covered with hinoki cypress bark.
Such early shrines did not include a space for worship.
Three important forms of ancient shrine architectural styles exist: "taisha-zukuri", "shinmei-zukuri" and "sumiyoshi-zukuri" They are exemplified by Izumo Taisha, Nishina Shinmei Shrine and Sumiyoshi Taisha respectively and date to before 552.
According to the tradition of ", the buildings or shrines were faithfully rebuilt at regular intervals adhering to the original design.
In this manner, ancient styles have been replicated through the centuries to the present day.