ABSTRACT
Per capita, CO2 emissions in Japan in 1995 were 2.72 tons2 per year, approximately one-third of which emitted from the building sector. The results of a life-cycle analysis of buildings show that 8 per cent of all CO2 emissions are related to the construction process, including CO2 emissions from manufacturing and transporting building materials, as well as emissions at construction sites. Some 23 per cent of total CO2 emissions are related to the operation of buildings such as air-conditioning, lighting and heating water. A few more emissions are related to maintaining and demolishing buildings. Approximately two-thirds of the damaging environmental impact of a building comes from the building operation; therefore, saving energy during its operation is critical in reducing the environmental impact of buildings.
