THE REVISED VERSION OF THE GB TOOL FOR SUBTROPICAL TAIWAN FROM THE BARRIER TO SUCCESS

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1 THE REVISED VERSION OF THE GB TOOL FOR SUBTROPICAL TAIWAN FROM THE BARRIER TO SUCCESS Chang K.F., PhD. Candidate 1, Chou P.C., PhD. 2, Chiang C.M., Dr.Eng 3, Chen I. C., PhD. 2 1 Archilife Environ-Control Research Center, Dept. of Architecture, National Cheng-Kung University, Tainan 70101, Taiwan. daphne@archilife.ncku.edu.tw & daphnekfc@hotmail.com 2 Shu-Te University, Dept. of Interior Design, Yen-chao, Kaohsiung County 824, Taiwan. paul@stu.edu.tw & cichieh@mail.stu.edu.tw. 3 Archilife Environ-Control Research Center, Dept. of Architecture, National Cheng-Kung University, Tainan 70101, Taiwan. Keywords: Subtropical Zone, Sustainable Building, GBTool, Taiwan Green Building Labeling System. Summary Sustainable development is the key goal of the state-of-the-art issue. More and more NGOs, such as iisbe, CIB and SBIS, have been established to offer integrated techniques for building sustainability. A knowledge bank as the exchange platform was announced via the sharing experiences of the worldwide experts accumulated from their own country. During the Sustainable Building Conference 2000 and Green Building Conference 2000, a discussion on sustainable buildings and green building issues was held. In the Sustainable Building Conference 2002, there was one session about the Green Building Tool and practices with an assessment tool that would be revised with time and space changes. This investigation is to explore regional customization of the GB Tool. That is, we want to find a suitable set of Issues and Weights from the general version of the GB Tool for Taiwan. Transfer of regional information from Taiwan Green Building Labeling System, the Construction Law, etc. into the GB Tool could be available to the climate and regulations. Therefore, the study would take one project that is certified with the Taiwan Green Building Labeling System to be assessed by the GB Tool. Comparing and analysis of these data can contribute more to the GB Tool for further research. Then, set up a rough assessment model of the GB Tool for the following operation and practice the previous project by a rough assessment model to estimate. Through comparison and analysis between the before and after assessment results, we would like to present the key factors, aimed to provide a sustainable Building assessment model that suits the sub-tropical characteristics and climate. 1. Introduction The abnormal changes of climate and the global environment that human dependent on have raised the importance of sustainable development issues these years. In addition to pursuing the balance between economic development and environmental preservation, many international institutes and countries have turned this into more specific action plans such as UNEP, iisbe, and CIB. These institutes provide the buildings and the whole environment more interactive information as resources for decision makers to improve the environment. Therefore, the Sustainable Building Conference 2000 defined sustainable building as the sustainable operation of buildings from building materials, buildings, and to the city not only considering the ecological, economic, and social influences, but also building more suitable models with respect to the regional characteristics. In the Sustainable Building Conference 2002 in Oslo, there was one session about the Green Building Tool and practices with an assessment tool that would be revised with time and space changes. Taiwan is a subtropical country with its climatic, geologic, and environmental specifics, the direction and contents of promotion sustainable building should be different from the frigid, temperate, or other OECD countries. Therefore, the study takes a residential project in southern Taiwan as an example assessed by the GBTool 2005 under the guidance of iisbe(international Initiative for a Sustainable Built Environment). During the process, we aim to find the international sustainable building trend, and provide a Sustainable Building assessment model that suits the sub-tropical characteristics and climate for researchers, and decision makers as references in Taiwan

2 2. Method When considering these tools and methods it should be noted that the aim of this analysis is primarily to focus on sustainability concepts, the structure, content and its intended use. Thus, GBTool2005 is made according to an evaluative framework, covering development progress building types, benchmarks and weighting value, performance assessment items, criteria, categories, scoring, results etc. (Baumann et al., 1999; Cole, 1999; Todd et al., 2001; Forsberg et al., 2004). This involves focusing on a variety of viewpoints from participants operating in widely differing environmental, climatic, socio-cultural, economic, and energy use contents to examine national and regional differences in projects (Cole, 2001). This investigation is to explore regional customization of the GB Tool. That is, we want to find a suitable set of Issues and Weights from the general version of the GB Tool for Taiwan. Transfer of regional information from Taiwan Green Building Labeling System, the Construction Law, etc. into the GB Tool could be available to the climate and regulations. Therefore, the study would set up a rough assessment model of the GB Tool by the AHP method. Aimed to provide a sustainable Building assessment model that suits the sub-tropical characteristics and climate. 3. System Description of GBTool 2005 Sustainable Building Assessment Suitable for the local circumstances is characteristic of GBTool 2005 applied to different countries and regional characteristics. This software tool was developed by iisbe on behalf of the countries participating in the Green Building Challenge process. The evaluation is mainly through the complete assessment calculations. This system is split into two parts: Module A and Module B. It can not only deal with new built and regeneration projects, but also apply to different process during the construction work from the predesign phase, the design phase, the construction phase, and to the operations phase according to different results coming from various data inputs. The building types it can apply to include hospital hotel or motel, industrial office, public institutional, public assembly, restaurant or food service, retail, school or university, supermarket, mixed-use project and etc... Three basic steps covering Input, Assessment and Output, have been used to compare the process of using the two assessment systems. The GBTool process requires that a third party (an organization or group not having a vested interest in the assessment results) should establish weighting values and benchmarks that will allow the system to reflect regional factors of building, technologies and even social and cultural factors. A second and separate step requires persons who are undertaking the assessment to complete worksheets that describe a specific building and associated factors in some detail. Assessments are then carried out by relating the weights and benchmarks previously established by the third party, to the specific characteristics of the building. The following, this paper will set up a weighting value model of the assessment issues and categories by the AHP method. The assessing procedure of GBTool2005 is shown as table 1. The Input step of GBTool 2005 is: inputting the basic background according to the site and environment by the developers, deciding benchmarks, and setting values for Issues and categories to reflect the varying importance by occupancy type in each region. Then, designers provide the design information and operating technologies to explain the architectural design, system, technology, materials, and emissions. We can get relative performance results from the weights of the factors through the evaluating calculations. From the analyses of the GBTool process, the results differ from the chosen weighting values, issues, categories, and benchmarks. The worksheets inputs are mainly divided into two parts. The first part from the developers, includes the project basic Information (Basic), the evaluation issues in the building life cycle (Issues), the weighting values of the assessment issues (Weight), the building site and urban data (context). The second part includes the design information of the buildings (DATA), the building emissions (Emission), calculation of consuming energy (Embodied) from the designer inputs. The Second Assessment step: The system provides consistency in the high-level Issues, the second-level categories and the third-level criteria. The high-level issues have seven assessment issues: A. Site Selection, Project Planning and Development; B. Energy and Resource Consumption; C. Environmental Loadings; D. Indoor Environmental Quality; E. Functionality and Controllability of Building Systems; F. Long-Term Performance; G. Social and Economic aspects. The second-level includes 29 categories and the third-level covers 109 criteria. The assessment scores are derived through the weighting of the scores at the lower levels, i.e. criterion scores are obtained through aggregating the weighted scores of constituent sub criteria. The overall building score is obtained through the weighted scores of issues. The weighting value, from the lower levels to the overall building, is a total of 100%. The Third Output step: The building assessment result covers absolute performance results and relative performance results. The scores range from -1to 5. 0 means acceptable practice, 3 is good practice, 5 is best practice.

3 Table1. The assessing procedure of GBTool2005 and the Inputs from developers and designers Process of assessment First step: Input The environment and the building complex from the related inputs Inputs from Developers Inputs from Designers regional customization remark Site basic data(basic) Module A The building life cycle(issues A) Module A Benchmark (Bmk A), (Bmk B), (Bmk C).. Module A Weighting values of issues(weight) Module A Building site and environment data (context) Module A& B Design information of the building (DATA) Module B Building Emissions (Emission) Module A& B calculation of consuming energy (Embodied) Module A& B Second step: Assessment (Ass A), (Ass B), (Ass C).. Module B Assessment Final weights(issues B) Module B Third step: Absolute Performance Results Module B Output Relative Performance Results Module B 4. The local adaptation of weighting values by the AHP method 4.1 The investigation process This paper adopts the AHP method (Analytic Hierarchy Process) to perform a sustainable expert choice for the local adaptation of weighting values. From the expert of sustainable building field, it covers three main part groups: designer & industry, government and academic & authorities. We send out 50 copies to investigate the different groups and get back 43 copies, which obtainable rate is 95%. But, there are 36 copies pass through C.I. (Consistence Index). The distribution data of the investigated experts is shown in Figure 1. Academic & authorities, 18, 50% Government, 9, 25% Figure 1 The distribution data of the investigated experts Designer & Industry, 9, 25% 4.2 The investigation result of assessment weighting values From the AHP method, it performs a sustainable expert choice for the local adaptation of weighting values. Tables 2 shows the statistics result of assessment weighting values by the different field experts: designer & industry, government, and academic & authorities. An average value is a geometric mean counted up by the assessment weighting values of the three groups, the figures as shown in Tables 2. Table2. The statistics result of assessment weighting values by the different field experts Assessment issues Designer & Industry Government Academic & authorities Average A. Site Selection, Project Planning and Development B. Energy and Resource Consumption C. Environmental Loadings D. Indoor Environmental Quality E. Functionality and Controllability of Building Systems F. Long-Term Performance G. Social and Economic aspects

4 Figure 2 presents the statistics result distribution of weighting values by the different field exper ts. The weighting values of all performance issues by different field experts: designer & industry, government, and academic & authorities were weighted close to the average values, with the standard deviation at virtually ± 5%. The three higher average weighting value of assessment issues are: B. Energy and Resource Consumption is 19%; C. Environmental Loadings is 21%; D. Indoor Environmental Quality is 16%. weight values Designer & Industry Government Academic & authorities Average A. Site Selection, Project Planning and B. Energy and Resource Consumption C. Environmental Loadings D. Indoor Environmental Quality E. Functionality and Controllability F. Long-Term Performance G. Social and Economic aspects issues Figure 2 The statistics result distribution of weighting values by the different field experts 5. Taking a Multi-unit Residential Building in the South of Taiwan 5.1 Background of this Project The evaluated target in this study is a new building. Therefore, during the operation process of GBTool 2005, it mainly focuses on the Design Process. The location of this project is in the metropolitan city of southern Taiwan Kaohsiung. The tall building is for residential use. The site faces a 60-meter road in the south and 8-meters street in the north. There is a lager 2 Art and Cultural Center nearby. A basic data of this project is: site area is m ; building area is m 2, 27 floors above grade, and 3 below grade, as shown in table3. Table2 The Basic data of this project Site Area/ Building Area m2/ m2 Total Floors 27 floors above grade/ 3 floors below grade Environment and Climate Sub-tropical climate (hot and wet) Annual Average temperature 25.1 Annual total rainfall mm /per yr Annual total sunshine hour hour 5.2 Input th e design information of this Project The users are responsible for inputting the project basic Information (Basic), the assessment phase and the evaluation issues during the building life cycle (Issues), select weighting values, as the above finished weighting values (Weight), Urban and Site Context (context), Design Data, and so on. The inputs of Basic Design Data of the Building from designers include Site-related information; General Project Information; Cost and Economics, Information on existing structure(s) on the site that are re-used; Information on new construction; Information on occupancies by type, by net area, and areas with natural or mechanical ventilation and cooling; Stormwater, potable water and effluent; Performance calculations for operating energy consumption; Planned and Actual on-site Renewable Energy and electrical demand; Estimated operating emissions; Information on the excavated materials re-used and recycled materials, Daylighting, Information on building technical systems (optional). But seven items are unavailable: Information on existing structure(s) on the site that are re-used; Performance calculations for operating energy consumption; Planned and Actual on-site Renewable Energy

5 and electrical demand; Estimated operating emissions; Information on the excavated materials re-used and recycled materials, Daylighting, Information on building technical systems (optional). As shown in table 4. Table4 Building Design Data Input Available or in this Project Design Data Available Unavailable Site-related information General Project Information, Cost and Economics Information on existing structure(s) on the sit e that are re-used Information on new construction Information on occupancies by type, by net area, and areas with natural or m echanical ventilation and cooling Storm water, potable water and effluent Performance calculations for operating energy consumption Planned and Actual on-site Renewable Energy and elec trical demand Estimated operating emissions Information on the excavated materials, re-used and recycled materials Daylighting Information on building technical systems optional 5.3 The Result of the Project From an assessment result, it shows that B. Energy and Resource Consumption, C. Environmental Loadings, D. Indoor Environmental Quality, and F. Social and Economics are available, but needs more data or unavailable. The analysis of local adaptation utilizing GBTool 2005 is as shown in Table 5. But the assessment issues of B. Energy and Resource Consumption, C. Environmental Loadings, and D. Indoor Environmental Quality are the three higher weighting values by Taiwan expert choice. Therefore, from the second-level categories, it displays not all the categories are unavailable or but needs more data. When analyzing the causes of issues in this project we consider the lack of complete investigations and statistics data of the detailed data in Taiwan, such as Total Life Cycle Primary Non-Renewable Energy in the Energy and Resource Consumption ; Greenhouse Gas Emissions and Other Atmospheric Emissions in the Environmental Loadings ; Daylighting and Illumination and Electro-Magnetic Pollution in the Indoor Environmental Quality Cost and Economics in Social and Economics, shown in Table 6. Therefore, now we can operate the system by re-distributing the weighting values of assessment issues, exclude unavailable and re-count the relative performance results. 6. Conclusion and Implications As the result of the above analysis of the local adaptation of weighting values by the AHP method, it presents the three higher average weighting value of assessment issues are: B. Energy and Resource Consumption is 19%; C. Environmental Loadings is 21%; D. Indoor Environmental Quality is 16%. This paper takes a multi-unit residential building in the south of Taiwan through the operation of GBTool In the General Project Information, it includes Design Data (DATA), the Building Emissions (Emission), and Calculation of Consuming Energy (Embodied). These three parts are unavailable to input the technical figures exactly, especially the Building Emissions (Emission) and Calculation of Consuming Energy (Embodied) because we lack of the related information and data in Taiwan. Besides, it obviously shows that two assessment issues are the emphasized direction in the international sustainable building development. Then, B. Energy and Resource Consumption, C. Environmental Loadings, D. Indoor Environmental Quality, and F. Social and Economics are unavailable to show actual performance results are the reasons for the incomplete database in Taiwan. Therefore, this paper has indicated the GBTool2005 system can adjust weighting values and assessment issues to suit local or conditions by the regional participants. From the operating and assessing an actual example, it can find which issues and techniques should be improved in design areas, construction industry for subtropical Taiwan. Acknowledgement Support from the National Science Council of ROC through grant No. NSC E in this study is gratefully acknowledged. And the support of Nils Larsson (iisbe) in clarifying certain issues relating to GBC and GBTool is acknowledged.

6 A Site Selection, Project Planning and Development B Energy and Resource Consumption C Environmental Loadings Table5 Actual performance results are available during Design Phase Assessment Description of Assessment Assessment list Number Available, but Available need more data unavailable A1 Site Selection N.A. A2 Project Planning N.A. A3 Urban Design and Site Development 17 76% 34% 0% B1 Total Life Cycle Primary Non-Renewable Energy 2 0% 100% 0% B2 Predicted electrical peak demand for building operations 1 100% 0% 0% B3 Renewable Energy 2 100% 0% 0% B4 Commissioning of building systems 1 100% 0% 0% B5 Materials 7 86% 14% 0% B6 Potable Water 3 67% 33% 0% C1 Greenhouse Gas Emissions 2 0% 100% 0% C2 Other Atmospheric Emissions 3 0% 100% 0% C3 Solid Wastes 2 100% 0% 0% C4 Rainwater, Storm water and Wastewater 4 50% 50% 0% C5 Impacts on Site 4 100% 0% 0% C6 Other Local and Regional Impacts 7 43% 14% 43% D1 Indoor Air Quality % 37.50% 0% D2 Ventilation 4 75% 25% 0% D Indoor D3 Air Temperature and Relative Humidity 2 100% 0% 0% Environmental D4 Daylighting and Illumination 3 33% 67% 0% Quality D5 Noise and Acoustics 4 75% 25% 0% D6 Electro-Magnetic Pollution - not yet active 1 0% 0% 100% E1 Efficiency of space utilization 1 100% 0% 0% E Functionality and E2 Design for maintenance of core functions Controllability of 1 100% 0% 0% during power outages Building Systems E3 Controllability 4 100% 0% 0% F1 Maintenance of building envelope F Long-Term performance 1 100% 0% 0% Performance F2 Flexibility and Adaptability 5 80% 20% 0% F3 Maintenance of Operating Performance 5 100% 0% 0% G Social and G1 Cost and Economics % 67% 16.50% Economic aspects G2 Social Aspects 7 86% 0% 14% Table6 Explanations on Evaluation issues are unavailable Reason during Design Phase Assessment Evaluation issues Categories Unavailable Reasons Energy and Resource Total Life Cycle Primary Non- Lack complete data in Taiwan Consumption Renewable Energy Greenhouse Gas Emissions Environmental Loadings Lack complete data in Taiwan Other Atmospheric Emissions Daylighting and Illumination Need more data Indoor Environmental Quality Electro-Magnetic Pollution Not yet active & Lack complete data in Taiwan Social and Economic aspects Cost and Economics Need more data References GB C Green Building Tool 2005, International Initiative for a Sustainable Built E nvironment (iisbe). Sustainable Building 2002 Conferenc e (SB 02), Oslo, Norway, Nils Larsson, Review of GB-Tool and Analysis of GBC 2002 Case-Study Projects, Cole, R.J. (1998) An Analysis of the GBC 98 Assessment Process, Proceeding of the GBC 98 Conference, Vol. 2, October, Natural Resources Canada, Ottawa, 251. Chiang, C.M., Chou, P.C., Lai, C.M. and Li, Y.Y. (2001) A Methodology to Assess the Indoor Environment in Care Centers for Senior Citizens, Building and Environment, 36,