The role of long-life buildings in protecting the global environment

In addition, architecture often loses value due to "functional factors" among "social factors." With the rapid changes in lifestyles and work styles, the demands on architectural space have become more diverse and sophisticated, and the skeleton of architecture up to now can no longer accommodate them. Electrical and mechanical equipment are also becoming more complex and unable to meet the demands of diversification.

From the perspective of the global environment, it can be said that a long lifespan of a building generally leads to a reduction in greenhouse gases (CO2). If we consider the lifespan of a building as about 50 years, depending on the purpose, it is said that the amount of CO2 generated during construction is about 1/5 to 1/3 of the amount of CO2 generated until demolition, which shows how much CO2 is generated during construction. Looking at the operation stage, technological innovation for energy conservation has progressed dramatically in recent years. The exterior walls, which are the "skeleton," have seen improvements in solar radiation suppression technology around openings, such as the use of low-E glass at openings and the installation of double skins and eaves, as well as the high insulation of exterior walls. The environmental performance of newly constructed buildings has improved significantly due to the improved performance and efficiency of the equipment, which is the "infill," and the spread of LED lighting equipment, which contributes to reducing CO2 emissions.

These technologies are being incorporated not only in new buildings, but also in the renovation of existing buildings. In long-life buildings, the "infill" parts will be renewed, and as technological innovation is expected in the future, the environmental performance of buildings will improve with each renewal. Architectural Design must work to improve the environmental performance of buildings when they are newly built, and must continue to study in order to further improve their environmental performance. They must also take into consideration future renewal design. This includes devising ways to minimize "work accompanying renewal" as much as possible, and securing space for bringing in and replacing equipment. These also affect construction costs and efficiency, so it is natural that they must obtain the full understanding of the client. Architectural Design designers design spaces in building designs, and at the same time, they are always considering the design quality and performance of the building as a whole, but they are also required to further raise their awareness of environmental quality. When a building is completed, it begins to operate with the performance and quality set at the time of design. Designers must understand that the environmental quality they set is one of the major factors that determine the value of a building.

Since the Great East Japan Earthquake, awareness of energy conservation has increased, and public understanding of the environment has also progressed. International environmental trends must be constantly monitored. At the 18th Conference of the Parties to the United Nations Framework Convention on Climate Change (COP18), held in Doha, Qatar, last December, it was recognized that the gap between the amount of greenhouse gas reductions actually required to keep the global temperature rise to within 2 degrees Celsius compared to pre-industrial revolution levels by 2020 and the reduction targets of participating countries is widening, and that measures to close the gap must be found. Long-life buildings are one solution to this reduction, and I hope that the necessity of this will be understood.