This article introduces the current situation of LCA for buildings. The research and development on LCA method of buildings started in 1990 as an activity of the Architectural Institute of Japan, and it became LCA guideline of buildings. By using of this guideline, the cost effectiveness evaluation tool to mitigate climate change was developed and applied by national and local government, and widely used by many private companies. As well as simplified LCA method was developed and introduced into the comprehensive assessment system for built environment efficiency named “CASBEE: Comprehensive Assessment System for Built Environment Efficiency” for all kind of buildings such as detached houses and large-scale commercial buildings. Furthermore, the human health impact assessment methods associated with indoor environment including indoor air pollution are conducted.
The simplified method of LCCO2 assessment and the environmental labeling for Comprehensive Assessment System for Built Environment Efficiency（CASBEE）are outlined as the practical application of LCA for buildings in this report. At the same time, the definition and the evaluation method of “Zero Energy Building” which is the latest environmental trend in the architectural design field are described.
Houses are designed and built to order, so they are not identical. Also, each house consists of many kinds of components which are manufactured by multiple companies, so it is difficult for housing designer to estimate its life cycle environmental load. However, the life cycle environmental load is an important index to evaluate a house, some estimating tools have been developed and used. In this article, two types of tools for detached houses are introduced.
This paper introduces a housing LCA and Environmental Load Database for building LCA. The Architectural Institute of Japan（AIJ）has developed the housing LCA as the open source software. The database is then derived mainly from the Japan Input/Output Table, which is not only for building but applicable to all the LCAs. Additionally the practical LCA which aims to contribute effective reductions in emissions from housing is discussed. Further the expansion of a housing LCA towards a comprehensive Social-LCA and the further efficiency by Hot Spots Analysis are also discussed.
Housing serves as an important basis for human life, and the establishment of a residential environment that promotes the health of residents is a pressing issue. In this social context, a large-scale nationwide questionnaire survey was conducted to examine the residential environment of detached houses and the residents’ health status. The Comprehensive Assessment System for Built Environment Efficiency（CASBEE）Health Checklist was used to assess the overall residential environment throughout Japan. The CASBEE Health Checklist covers residential environmental factors such as thermal condition, air quality, sound environment, lighting, sanitation, safety, and physical obstacles. Respondents were also asked about their current health status and that of their family members. The questionnaire results were cross-tabulated, and odds ratios and significance probabilities（Fisher’s exact text）were calculated. Results show that the overall residential environment was likely an important determinant of health and was associated with disease prevalence among residents. Odds ratios tended to be less than 1.0 in all cases, indicating that low disease prevalence was associated with a good residential environment. Furthermore, lower odds ratios were found for residents living in much better residential environments.
This paper reports on the recent trend in the use of quantified environmental information on the life cycle of buildings. In Japan, the use of the EcoLeaf Environmental Labeling and the Carbon Footprint of Products（CFP）Program to disclose the quantified environmental information on building materials is growing. The CFP declarations for a number of buildings are also already made, and this is expected to promote the development of lower-carbon materials and more efficient construction methods through the assessment of all the life cycle stages other than of the use stage alone. Quantified environmental information is actively used in policymaking abroad. The latest version of the Leadership in Energy and Environmental Design（LEED）, a scheme developed in the USA to assess the environmental performance of buildings, uses Environmental Product Declarations（EPDs）to assess building materials. The Construction Products Regulation（CPR）in Europe recommends the use of EPDs to assess the sustainable use of construction materials and the impact of construction works on the environment. In Europe and the USA, the number of construction companies utilizing supplier EPDs to implement eco-design is growing and this trend appears to be influencing the international standardization. According to the results of a questionnaire survey for building practitioners in Japan, approximately 70% of the practitioners found the topic interesting. This indicates the current assessment methods and the lack of take-up are some of the major issues in the construction sector in Japan.
Objective. Since 2011 great East Japan Earthquake, operating ratio of coal-fired power generation has been increasing and the amount of emission of fly-ash which is by-product of operation also has been increasing. Therefore, recycling of fly-ash needs to be accelerated to consider the environmental responsibility. Fly-ash is used as a supplementary cementitious material in the production of cement concrete. A well-proportioned fly ash concrete mixture will have improved workability of fresh concrete and long term strength and mass transfer resistance of hardened concrete when compared with a normal cement concrete. Currently, some concrete plant has been shipping fly-ash concrete positively in Shikoku Island in Japan and giving satisfactory results of shipping. In future, informing the effect of concrete quality improving effect and Life Cycle Cost (LCC) reduction effect due to quality improvement of usage of fly-ash. This research aims on developing life cycle model of infrastructure used concrete used fly-ash as binder and calculating LCC for investigating the effect of LCC reduction of fly-ash used concrete. Results and Conclusions. In the study of chloride damaged road bridge and caisson constructed by steel reinforced concrete, LCC of fly-ash used concrete calculated higher than normal concrete, though LCC per year of fly-ash used concrete is much lower than normal concrete due the life time of fly-ash concrete estimates much longer than normal concrete. In the study of carbonation effected road bridge constructed by steel reinforced concrete, life time of both structures are the same, therefore both LCC and LCC per year is the most lowest in case of normal concrete due the materials cost of fly-ash used concrete is more expansive than normal concrete. Therefore, fly-ash using for concrete to reduce LCC of infrastructure is effective for chloride damaged structures or combined carbonation and chloride damaged structure.
Meta-analysis is a method that integrates multiple existing studies through statistical processing and is typically used in academic fields such as medical care, psychology, and education surveys. Some studies exist in which they apply meta-analysis to Life Cycle Assessment（LCA）results of automobiles, but the vehicle types and target life cycle stages are limited. In this study, we applied the meta-analysis method to the life cycle of automobiles classified by vehicle type and energy sources to estimate greenhouse gas（GHG）emissions. A literature review of 27 peer-reviewed articles was conducted to extract the LCA data that were used in this study. The life cycle stages were classified into four stages: Battery, Other production, Use, and Disposal. The results showed that GHG emissions during the use stage represented approximately 80% of the entire life cycle for gasoline, diesel, and hybrid vehicles. For plugin hybrid vehicles and electric vehicles charged with electricity from electricity mix or fossil fuel generation methods the use stage accounted for approximately 50-70% of the entire life cycle. Moreover, the results showed that GHG emissions could be reduced by approximately 75-80% if gasoline and diesel vehicles are replaced by electric vehicles that are powered by electricity generated from renewable energy. However, when electric vehicles are powered by electricity generated from fossil fuels, the GHG emissions can be equivalent to gasoline and diesel vehicles. The results also showed that the amount of GHG emissions depend significantly on the travel scenarios and the source of electricity generation. Therefore, the selection of these factors are of major importance when conducting an LCA study of automobiles.