The Sustainable Strategy of Chinese Quadrangles

The sustainable strategy of Chinese quadrangles

According to Central Intelligence Agency (2016), China (without disputed areas) ranks as the third largest country among all countries in the world. Such geographic conditions bring different and various climatic conditions to the land. China has developed different cultural and living habits between the southern and northern areas. However, people can find common factors in both cultures regarding one of the traditional vernacular dwellings: Chinese quadrangles. Most of the time, Chinese quadrangles refer to the type of residences in Beijing, China, which people usually call "siheyuan" (四合院). Chinese quadrangles have a long history. The first quadrangle emerged in China about 2000 years ago (Wang, 2011, pg. 122). This paper focuses on discussing the sustainable perspectives of siheyuan.

Although climate conditions are totally different in southern and northern China, the quadrangle residence type has been accepted by people in both areas. The Chinese government divides China into five thermal climatic regions (Gong, Akashi, and Sumiyoshi, 2012, pg. 47). In Figure 1, Beijing is located in a cold region. Thus, the main purpose of building a compound

residence was to offer a comfortable thermal environment and living spaces for people who lived without modern technologies.

Significantly, the siheyuan has allowed the community to live sustainably for centuries (Chen, Glicsman, and Scott, 2007). Siheyuan is a residence with one courtyard surrounded by rooms at all four sides; see Figure 2. All rooms are connected with pathways. According to Li (1996), the Chinese believed that the shape of the land was square, but the sky was a circle. Consequently, people built the courtyards in a square shape. The shape of the Siheyuan is a key feature that grants the residents protection from windy winter and gets enough sunshine for human needs. First of all, the square shape allows the residents to have the front facing south and the back facing north. In winter, the worst condition is that wind comes from the northeast with an average speed of eight meters per second (Shi, 2013). Shi (2013) points out that, "high wind speed which exceeds the wind comfort threshold of people will decrease both the indoor and outdoor thermal comfort, meanwhile put negative influence on people's activities" (pg. 495). Thus, in order to protect themselves from the strong wind, windows were usually not installed in the outside layer of the wall. All of the windows and doors face the courtyard.

Additionally, Sun (2013) mentioned that the enclosure layout effectively protects people from strong winds, as confirmed by Shi. Shi indicates that the wind cannot blow into any room of the Siheyuan even if all of windows and doors remain open (2013). Shi (2013) also proved that the temperature difference between the inner courtyard and open environment is 36.5 Fahrenheit (see figure 5). Without using air conditioners or heaters, which consume electricity and gas, Siheyuan is able to maintain the temperature as well as protect residents from strong wind. In the summer time, Siheyuan allows for ventilation. According to Shi (2013), in figure 3, rooms H1 and H2 will have cross-ventilation between them, meaning the wind can blow into all other rooms within Siheyuan as well. Importantly, in summer, Siheyuan will help reduce the temperature. Shi (2013) suggests that "the majority of the indoor and central courtyard area is about 35.6 Fahrenheit lower than the outside (see figure 4)." Without any energy consumption, the Siheyuan can provide natural ventilation and effectively reduce the temperature to create a comfortable thermal environment for residents.

Meanwhile, Siheyuan never sacrifices its cultural beliefs to achieve the goal of a sustainable living environment. Rooms located at the four sides all represent different identities in the family. People cannot live in whatever room they want. All family members must follow the rules, which are found in Confucian ethics (Mu, 2012). Bedrooms that face south are for the