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Interest in sustainability has continued to grow throughout the world. This encompasses a wide range including reduction and eventual reversal of dangerous environmental impacts caused by emissions to the air, water, and land. Sustainable development also includes the husbanding of nonrenewable resources for future generations. In the broadest sense, this involves intelligent planning of land use as well as concern for materials such as organic feedstocks and scarce metals. To maintain a proper balance of people’s needs and available resources requires a simultaneous concern for the demand sector as well as the supply side of the problem.

As rapidly developing countries grow, they will consume a larger share of global resources and could produce damaging levels of emissions. In many countries, these problems are compounded by the concentration of the population in large cities. Densely populated areas accelerate the depletion of land and local resources. Figure 1 shows one estimate of the world consumption of energy and the projected consumption one century hence. Currently, a large portion of the world’s energy is consumed by the relatively modest population in Western Europe, North America, and the Pacific Rim. If present trends continue, China and India will consume a preponderance of the world’s energy by the end of this century. One study projects total energy consumption of the world will increase from approximately 350 EJ (350 × 10 J) in 1990 to 1300 EJ in 2095. China (China, North Korea, Mongolia, Vietnam, Laos, and Kampuchea) alone is projected to consume approximately 500 EJ by 2095, more than the entire current world energy consumption (Edmonds, Wise and Barns 1995). For this reason, it is vital to ensure that new residential buildings in China’s rapidly growing cities are built in a sustainable fashion.

New urban housing in various areas of urban Chinese cities appears at first review to be relatively unsustainable. Poor performance of the building fabric, a lack of responsiveness in the design to the harshness and forces of the climate, and an absence of a relationship of housing areas to an urban transportation infrastructure stay in one’s mind as significant deficiencies in a more comprehensive environmental strategy.

This chapter addresses strategies for responsible materials use and good construction practices for low-energy residential buildings in China. Achieving well-built, energy-conscious designs will be the result of a myriad of diverse efforts from design and engineering professionals. It will also require the commitment of the local, regional, and national authorities. Therefore, issues that range from materials extraction, land use, and construction materials industry standards to the proper detailing of the exterior envelope must all come together to contribute to the making of energy-efficient buildings.

While the reduction of heating energy remains an important goal in China, there is now a pressing need to address cooling energy. The use of air-conditioning is burgeoning as occupants increasingly can afford to purchase and operate cooling equipment. In Beijing, for example, formal surveys as well as first-hand experience of the authors and Chinese colleagues suggest that while many people use air-conditioning, others who are unaccustomed to it or are more careful about shading and ventilating their units are able to remain thermally comfortable without it. This research strengthens an understanding of how housing can be designed and operated to provide a viable (comfortable and affordable) alternative to air-conditioning equipment.

Wind can be a building’s “friend” because it can naturally ventilate the building, providing a comfortable and healthy indoor environment, as well as saving energy. Conventional design approaches often ignore opportunities for innovations with wind that could condition buildings at a lower cost, while providing higher air quality and an acceptable thermal-comfort level by means of passive cooling or natural ventilation. Natural ventilation can be used for cooling in the spring and autumn for a moderate climate (e.g., Nashville, TN), the spring for a hot and dry climate (e.g., Phoenix, AZ), the summer for a cold climate (e.g., Portland, ME), and the spring and summer for a mild climate (e.g., Seattle, WA). Natural ventilation can also be used to cool environments in a hot and humid climate during part of the year (e.g., New Orleans, LA) ().

As the previous chapter demonstrated, if a building is properly designed, natural ventilation can provide both a comfortable and healthy indoor environment as well as energy savings. Most architects and designers know about the principles of passive solar heating and can indicate how they desire small buildings to also take advantage of natural ventilation, as shown in Figure 1. Natural ventilation and thermal comfort, however, are difficult to understand and model, even for simple buildings. It is important that the architects and engineers collaborate early in the design process when key decisions about master planning and building geometry are made.

Daylighting is usually considered an attractive option for illuminating interior spaces in buildings because it is to a large extent cost-free. There is no need to generate electricity, with its attendant emissions of carbon dioxide and other pollutants, and no need for the end user to pay for that electricity to power electric lights. The infrastructure for lighting — from the generation station to the lamp — must be purchased for use at night and perhaps during overcast conditions, with the result that capital costs for electric lighting are unchanged. Daylighting however, can substantially reduce energy consumption for lighting and can also reduce peak electricity demand.

The goal of the Sustainable Urban Housing in China Project was to develop research on sustainable building principles as applied to housing projects within varying urban regions in China. The lessons learned are the result of a direct relationship between research and practice and are grounded in the diverse range of sociological, political, and economic factors of professional practice. Through the collaboration with local design institutes and developers, the MIT Sustainable Urban Housing in China group worked on schematic design schemes for projects in Beijing, Shanghai, and Shenzhen.

The Beijing Prototype Housing Projects, including the 12×12 house and the 12 × 24 prototypes, were designed in 1998 in collaboration with Tsinghua University for the Beijing Vanke Co. Ltd. The goal was to design a modular prototype for sustainable urban housing that could be applicable to various medium-density sites. These prototypical designs were the first projects explored by the Sustainable Urban Housing in China Group.