Comparison Criteria and Certified Scores between G-SEED and LEED Certification Systems in Office Building Cases Speakers: Mok, Seon-Soo (KICT) 1 ; Cho, Dong-Woo (KICT) 2 ; 1 Korea Institute of Civil Enginerring and Building Technology, Gyeonggi-Do, South Korea 2 Korea Institute of Civil Enginerring and Building Technology, Gyeonggi-Do, South Korea Abstract: This study aims to compare certification system and grade results by analyzing on reclasification of the criteria and achieved credits from the four office buildings which certified two systems, Green Standard for Energy and Environmental Design (G-SEED) and Leadership in Energy and Environmental Design (LEED). Archived credits in both certificationof four office buildings bring similar grade results included high considerations of evaluation categories such as energy saving and indoor environment even thought they have difference rating methods And each certification has own characters such as ecological environment in G-SEED, Innovation in Design and regional priorities in LEED through regional environmental condition and policy. From the study, it discovers that comparative sustainable building evaluation system should compose with the criteria for domestic standard with local environmental consideration and with the compatible criteria for global standard.then participated countries could agonized over global concerns together with same mesurements. Keywords: G-SEED, LEED, Office Building, Certification Criteria, Archived Credits Propose of Study Green Standard for Energy and Environmental Design (G-SEED) is Korea Green Building Certification System, which was introduced targeting multi-residential buildings to be cosupervised by the Ministry of Land, Infrastructure & Transport and the Ministry of Environment, Korea Government in 2002, for certify 10 difference building types included multi-residential building, office, school and commercial building. The status of G-SEED certification (as of September, 2013) takes 30.7% of multi-residential housing, 34.75% of school and 12.94% of office buildings, is increasing continuously due to expanding mandatory and supporting federal and state incentives. Leadership in Energy and Environmental Design (LEED) was founded by US Green Building Council, in 1993, is a certification system to the environmental-friendly building certification in the USA. However, LEED certificates for office buildings, owned by global companies are increasing currently in Korea. In this study, it is intended to suggest the direction of G-SEED certification criteria in order to respond to the global standard criteria in future through the re-constructed LEED evaluation criteria and credit rates for office building cases. 1585
Research Method G-SEED and LEED reclassified criteria in order to compare the certification criteria credit rate for office buildings. And four case studies in Korea, which certified G-SEED and LEED, were analyzed the archived credits through the re-constructed criteria to find the differences and similarities. Theoretical Review G-SEED is a domestic certification system evaluating the environmental-friendly buildings for residential building types as multi-residential housing and detached house and nonresidential building types as office, school, retail, hotel and other buildings divided with new and existing constructions. G-SEED certification system is divided into 7 categories, that are Land Use & Transport, Energy & Environment Pollution, Materials & Resources, Water Management, Management, Ecological Environment and Indoor Environment with minium credit required in mandatory criteria into four grades. LEED evaluates by dividing the areas into new construction,existing buildings:operation management,core & shell,commercial interiors, school, healthcare, retail, homes and Neighborhood. The certification criteria of LEED divided into the following 6 categories, that are Sustainable Sites(SS), Water Efficiency (WE), Energy & Atmosphere (EA), Materials & Resources (MR), Indoor Environmental Quality (IEQ) and Innovation &Design Process (ID) with the minimum performance criteria by satisfying the prerequisites. And an average grade is decided by totalling the evaluated scores from each item and the final scores are divided into 4 grades. Objective G-SEED New Building: Multi-residential hosing, Residential complex, Office, School, Retail, Hotel, Home, and the other Building LEED New Construction, Existing Buildings, Operation Management, Core &Shell, Commercial Interiors, School, healthcare, retail, homes, Neighborhood Assessment Categories 7 Categories: Land Use and Transport, Energy and Pollution, Materials andresources, Water Management, Management, Ecological Environment, Indoor Environment 6 Categories:Sustainable Sites, Water Efficiency, Energy & Atmosphere, Materials & Resources, Indoor Environmental Quality, Innovation &Design Process, Rating 4 grades:green1,green2,,green3,green4 4 grades:platinum,gold,silver,certified Significant Request minimum credit in mandatory criteria Figure 1 Introduction of G-SEED and LEED Request prerequisites in each category Comparison of Certification Criteria Credits between G-SEED and LEED The evaluation criteria of LEED were reclassified based on the detailed certification criteria of each among 7 categories of G-SEED certification criteria in order to compare the certification criteria credit rate of G-SEED 2008 version with the average rate of LEED NC2.2, 2009 and CS 2.0 as below. 2586
1. Land use and Transport In G-SEED criteria, Feasibility of the measure to prevent interference of daylight right (+1.77%) and Proximity to public transportation (+2.67%) are higher than evaluation rate of LEED criteria and in LEED criteria, Land of the ecological value of the existing (+5.68%) is higher than evaluation rate of G-SEED criteria. In G-SEED criteria, Building coverage ratio and high level of information and communication equipment have a total of 41.67% with independent standards. In LEED criteria, Development Density & Community connectivity, Alternative Transportation and Maximize Open Space have a total of 39.53% with independent standards. As an criteria showing the topographical characteristics the most, LEED shows the characteristics with which the status of the outskirts of land is comprehensively evaluated as well as the land use within a site is evaluated. 2. Energy and Pollution G-SEED and LEED both Energy consumption criteria represents the difference ± 0.03%, and mandatory or pre-requisites to specify the minimum score to be obtained. In G-SEED criteria, Saving lighting energy (+19.02%) and Preventing use of OZone depletion materials (4.84%) are higher than evaluation rate of LEED criteria and In LEED criteria, Renewable Energy (9.2%) is higher than evaluation rate of G SEED criteria. In G-SEED criteria, 10.34% of Carbon dioxide emissions has independent standard and In LEED criteria, Measurement and Verification, Heat Island Effect and Lighting Pollution Reduction have a total of 22.28% with independent standards. Although there are some differences in the aspect of the calculation criteria of the categories, Energy and Renewable Energy between G-SEED and LEED, it is necessary to revise and develop the criteria and to strengthen the certification criteria under the concept of the Life Cycle Assessment (LCA) since this category is the specialty ones having the importance with the highest evaluation scores. 3.Materials and Resources In G-SEED criteria, Use of environmental-friendly products (+3.75%), Saving resource by reusing structure of existing building (+10.24%) and Saving resource by reusing nonbearing walls of existing building (+3.93%) are higher than evaluation rate of LEED. In LEED criteria, Recycled Content, Rapidly Renewable Materials (+10.57%) is higher than evaluation rate of G SEED criteria. In G-SEED criteria. New technology industrialization process and the environment and Saving consumption goods in toilet have a total of 33.34% with independent standard. In 3587
LEED criteria, Regional Materials, Certified Wood and Construction Waste Management have a total of 39.88% with independent standard. G-SEED has shown its high performance as the system for saving materials and resources by evaluating based on the installation of the facilities. It is necessary to introduce the evaluation criteria evaluating the usage rate of local materials and resources to develope compatible criteria. 4. Water Management In G-SEED criteria, Rainwater use (+6.35%) is higher than LEED evaluation rate and in LEED criteria, Storm water Design (+3.17%), Water Use Reduction (+1.58%) and Water Efficient Landscaping (+1.58%) are higher than in G-SEED evaluation rate. The major difference of both evaluation systems are evaluating based on whether the facilities installed or the usage rate. 5. Management In G-SEED criteria, Appropriateness of provision of operation / management (+23.33%) is higher than evaluation rate of LEED criteria and in LEED criteria, Enhanced Commissioning (+63.33%) is higher than evaluation rate of G-SEED criteria. Modifiability of space and system plan for users (40%) has an independent standard in G-SEED criteria. It should be revised in order to seek the operation and management of buildings which obtained a G-SEED certification and to be evaluated based in the monitoring for managing continuously and the evaltion criteria for the existing buildings are needed to be expanded. 6. Ecological Environment Only the ecological environment as a separate category in G-SEED with Ratio of natural ground (36.84%)> Ecological Environment considering to apply the artificial environment landscaping technique (31.58%)> bio-top composition (31.58%) are appeared. 7. Indoor Environment In both G-SEED and LEED criteria, prevent residents being exposed to smoking (9.68%) and the outside air vent design (9.68%) represent mandatory or pre-requisites to specify the minimum score to be obtained. And design introduced natural ventilation and comfortable indoor air environment shows only the differences ± 0.13%. In LEED criteria, Low-Emitting Materials (+16.21%), Outdoor Air Delivery Monitoring (+3.39%), Indoor Chemical & Pollutant Source Control (+6.58%) and Controllability of Systems (+15.59%) are higher than evaluation rate of G SEED criteria. In G-SEED criteria, acceptable room for external noise, Providing an indoor rest and recharge space for residents, comfortable indoor environment for the residents and 4588
Design for barrier-free have a total of 35.48% with independent standards. In LEED criteria, Construction IAQ Management Plan-During Construction, Construction IAQ Management Plan-before occupancy have a total of 12.59% with independent standards. As a category showing similar purposes of both certification criteria, the importance of the indoor environment among the living environments for domestic residents is increasing rapidly. So, the evaluation criteria suggesting the design & management methods considering the indoor environment from the design stage is needed. 8. Innovation in Design, Regional Priority Credits Innovation in Design and Regional Priority Credits are only categories used by LEED. The credits are given by making a higher level of suggestion than a standard evaluation criteria and by suggesting and evaluating some innovative designs which still are not suggested based on the current criteria and also through the participation of LEED AP (Accredited Professional). The additional credit is regional priority for adjusting regional environment condition. An Anaysis of Archieved Credits of G-SEED and LEED from Office building Studies G-SEED and LEED archieved credits of four office buildings in Korea reclassified evaluation criteria by total 9 categories included 7 categories, base on G-SEED and sparated LEED categories Innovation and design and Regional Priorities compared with acquiring sector as below. The categories, higher credits archived in G-SEED are Energy and pollution (average 19.93%), and Materials and resources (5.62%). The categories, higher credits archived in LEED are Land use and transport (32.33%)> Management (21.48%)> water management (4.76%)> indoor environment (4.12 %). However, the difference in percentage grades is acquired criteria of the two evaluation systems but in the certification criteria, the final total score obtained by comparing the ratio showing the difference only 1.78%. The difference of two evaluation certification standards respond for each regional sector weights of the living environment and the built environment-related policy measures. As the comparison of percentage of the total score results does not obtain much difference. 5589
Figure 2 Comparsion of G-SEED and LEED criteria in office building cases Conclusion In this study, G-SEED and LEED grade rate were compared through the re-classification of LEED criteria. Four office building cases obtained by comparing the acquisited score results were analyzed based on the similarities and differences. Land use and transport of each certification systems found significantly difference in average, which is the difference in geographical conditions and the environment caused by traffic features identified. Energy and pollution criteria is similar between G-SEED and LEED but evaluation methods and aeverage rate are different. Then the archieved grades in the two obtained by building the differences can be found. Materials and resources shows differences in assessment methods such as LEED evalates using the usage rate of materials and resources in local supply. Water Management of both evaluation is similar to the average amount of the certification criteria and evaluation purposes. Management, which shows the difference between the overall certification standards such as reported-oriented in G-SEED and Commissioning evaluation in LEED. Indoor environment is similar to the purpose of the certification standards and also independent criteria distributed in the form of a variety in category. 6590
Therefore, Energy and pollution and Materials and resources are higher proportion of G- SEED and Land use & transport, Management, Water management and Indoor environment are higher proportion of LEED in terms of overall score results through the analysis of comparing rates. The difference in percentage grades is acquired criteria of the two evaluation systems but in the certification criteria, the final total score obtained by comparing the ratio showing the difference only 1.78%. Generally, many criteria details of the G-SEED and LEED ratings are identical or similar to the target based on an independent assessment form to operate. And it also found the major difference such as G-SEED related to planning and installation of the evaluation items and criteria of evaluation, LEED is actually installed in accordance with standards to evaluate efficiency. The difference of two evaluation certification standards respond for each regional sector weights of the living environment and the built environment-related policy measures. The sustainable certification systems currently in operation each location, country expect in accordance with the regional characteristics and institutional environment to promote the development. Further more, the implementation of the standards for International concerns such as environment and sustainable architecture can prevail by taking advantage of the mutual evaluation and integrated assessment and global standard based on the results of the current responses to climate change and environmental pollution research and development proposed measures are expected to pursue together. Reference G-SEED Certification Criteria, MOLIT Notification No.2010-301 G-SEED Certification Data (Sep. 2013), homepage: www.molit/go/kr LEED, USGBC, www.usgbc.org 7591