In northern China, heating is represented by kang. The kang is a living and sleeping platform, a heated bed. It is constructed of brick, adobe or stone and consists of three parts: a fireplace, a kang proper and a chimney. Beneath the flat surface of the kang are flues, which conduct hot air from the fireplace through to the room. The kang allows energy to be conserved; its surface temperature of about 40 degrees C can largely be maintained overnight. It is used as a bed at night; bedding is laid out for sleeping but is put away in the morning. During the day it provides a large warm platform upon which people undertake many household activities. The kang usually occupies from one-third to one-half of the area of a room; but the entire floor of a room can be constructed and heated in this manner, in which case it is called dikang, literally a heated floor (di meaning floor). The heated bed and the heated floor are technically similar, but each developed in conjunction with a distinctive way of life, either sitting on the floor or sitting on furniture.