Windows in new buildings in Korea are equipped with double or triple glazing, a low-E coating, and gas injection between the panes of glass, in accordance with the regulations for the reinforced insulation of windows. However, these windows have certain issues, such as thermal transmittance variations and injected gas leakage. In this study, we investigated the current status of double-glazed windows filled with argon gas and analyzed the actual deterioration degree in terms of insulation performance via field experiments and simulations. Accordingly, we manufactured a 26-millimeter low-E double-glazed window test specimen and conducted tests in accordance with the KS F 2278 standard. The test results indicated that the thermal performance decreased by 10.9% when the argon gas filling rate was reduced from 95% to 0%. The simulation results showed that the thermal performance of windows that were insulated using only glazing decreased by 22.6% with the decrease in the argon gas filling rate; the thermal performance of the double-glazed windows also decreased by 13.6%. A comprehensive analysis of the field surveys and simulations predicted a 92% probability that the argon gas filling rate of double-glazed windows would be below 65% by two years after completion, in addition to a ~4.3% decrease in thermal performance.

G-SEED(Green Standard for Energy and Environmental Design) is operating in Korea as a certification system to evaluate the environmental friendliness of buildings. Buildings are generating loads such as carbon dioxide emission, energy consumption, the consumption of resources, destruction of natural ecosystem, change of global climate, pollution of indoor environment, and waste generation. For this purpose, a green building certification system has been introduced. In the green building certification system, evaluation of buildings through methods such as utilization of natural energy, adoption of energy saving system, rainwater management, etc., is induced to reduce environmental load. These certification systems are operated by each country. The level of the certification system is different according to the characteristics such as climate environment. BREEAM in the UK and LEED in the US are operating a version for international certification as well as domestic certification. In this study, analyze the certification system which operates the global version such as BREEAM, LEED. And to investigate the differences between domestic and international versions of each version of the certification system. Certification items classified as reflected by climate characteristics, national characteristics reflected items, general items, such as attempts to analyze the rating system. And certification items were grouped into general “Global certification items” having no specificity for locality and “Local certification items” that differ by each locality according to social, environmental, and political factors. Using the analysis results that comparison of LEED and BREEAM, the study then aims to ascertain the possibility of whether the G-SEED can be used to certify international buildings. And explore the possibility of developing international version of the G-SEED and indicate the direction of G-SEED amendments that may arise in the future. The study results would be available as basic data at the development of G-SEED for international version.

G-SEED is a system that comprehensively evaluates the eco-friendliness of buildings. As a carbon reduction strategy in buildings, the role of G-SEED system is becoming increasingly important. In this study, the main revisions of G-SEED since 2016 are reviewed, and data related to certification results of multi-residential buildings are analyzed in detail. In addition, considerations for future revisions are reviewed. G-SEED has been reorganized six times since the 2016 revision, and only the 2016-2 version and 2016-6 version have been upgraded in difficulty. In particular, certification items for materials and resources have been strengthened. In the analysis of the certification results of multi-residential buildings, the score analysis by specialized field and the acquisition rate by certification items were analyzed. Energy and environmental pollution scored highest in the score analysis, while the ecological environment scored the lowest. Acquisition rate analysis revealed that 17 items were acquired at a level of 90%, and the lower five items were acquired at less than 30%. In addition, 17 items with a biased specific grade were identified through acquisition rate analysis. Based on these observations, the following issues need to be addressed in future revisions: 1) set the final grade and review the target score according to the level of difficulty for each specialization 2) review the existing required items or the mandatory items. 3) review whether to maintain certification items low acquisition rate. 4) review the level of difficulty adjustment within the underweight or overweight items with a specific grade.

In this study, the certification status and scoring trends of nonresidential buildings that received the Green Standard for Energy and Environmental Design (G-SEED) certification between 2016 and 2023 were analyzed. The aim was to identify trends and areas for improvement within the certification system. Certification data were examined based on various factors, including year, rating, region, certification version, building area, and public/private classification. Further, certification scores were analyzed by final grade and specialized field scores. The analyses revealed key characteristics and trends in the evaluation of nonresidential buildings under the G-SEED system. First, significant differences were identified in building area, public/private ratios, average scores, and specialized field scores depending on building use. Future revisions to the G-SEED system should consider refining the classification of building use and adjusting the evaluation criteria accordingly. Second, private buildings exhibited a higher proportion of certification acquisition than that of public buildings. To further encourage certification in the private sector, policy support and incentives (e.g., tax benefits) are recommended. Third, school facilities exhibited different trends compared to other building types, with relatively low scores. This finding underscores the need for evaluation criteria and policies that address specific characteristics of school facilities. Fourth, the analysis of specialized field scores indicated that the operation and maintenance (O&M) field contributed the most to overall scores, highlighting the need for revisions to balance the difficulty and discriminative power of certification criteria. Enhancing the evaluation framework and redefining the direction of each specialized field are crucial for improving the G-SEED system.

In this study, we analyzed the certification status and scoring trends of residential buildingsparticularly multi-residential and general housing-that received Green Standard Energy and Environmental Design (G-SEED) certification between 2016 and 2023. The study aimed to identify trends and areas for improvement within the certification system. Certification status was analyzed across multiple factors, including year, rating, region, certification version, number of units, and public/private classification. Certification scores were reviewed by final grade as well as by scores in specialized fields. The findings revealed the characteristics and trends in the evaluation of residential buildings under the G-SEED system. First, most certifications were at the [Green 4] level, with a notably low rate of [Green 1] certifications, suggesting a need for enhanced design and technical support, as well as stronger incentives. Second, the certification data showed that certified buildings were concentrated primarily in the metropolitan area, highlighting the need for regional cooperation and locally tailored policies to promote green building certification in other regions. Third, a higher proportion of certified buildings in the private sector compared with those in public sector indicated a rising interest and demand for green construction within the private sector, suggesting that policy support and tax incentives could further encourage participation. Lastly, an analysis of specialized fields revealed that the "5. Maintenance" category contributed significantly to overall scores, suggesting the need for differentiated approach and adjustments to difficulty levels for this category in future G-SEED updates.