Abstract:The Korean government has established a national plan for the promotion of zero energy buildings to respond to climate change and energy crises. To achieve this plan, several energy efficiency policies for new and existing buildings have been developed. The Building Energy Efficiency Certification System (BEECS) aims to promote the spread of high energy-efficient buildings by evaluating and certifying building energy performance. This study discussed Korean building energy efficiency policies and analyzed especially the influence of the BEECS on the actual energy consumption of a residential building and calculated energy performance of non-residential buildings. The BEECS was evaluated to have influence on gas and district heating consumption in residential buildings. For non-residential buildings, a decreasing trend was shown in calculated primary energy consumption in the years since the BEECS has been enacted. Appropriate improvements of the certification system were also discussed by analyzing relationship between building characteristics and their energy consumptions.

Aapartment houses account for more than 60% of the total of residential buildings to be built in South Korea. In particular, a high-rise apartment house with 21 floors or more has steadily increased in densely populated areas. The heating and cooling energy demand of the apartment house is greatly affected by the shape and the thermal insulation of its building envelope. In addition to its functional efficiency, the shape of building envelope in a high-rise apartment house is considered to be an important factor for the urban landscape with diverse construction methods and materials. In this study, we analyzed the heating and cooling energy demand depending on the effective heat capacity of building structure and the installation position of thermal insulation materials as the design conditions of high-rise apartment houses. This study used the ECO2 energy analysis program for the building energy efficiency grading certification system in South Korea.

Thermal insulation materials are among the simplest ways of decreasing heat loss in the buildings. When insulation materials are installed in the walls, floors and roof of a building to prevent heat loss from the building, materials must be used with the appropriate structural and thermal properties. In this paper, a laboratory test of the thermal conductivity and cell structure of building insulation materials was conducted. From the experiment results, the correlation expression between thermal conductivity and density was derived. In the case of the insulation materials that were made of expanded polypropylene (EPP), as the density increased, the thermal conductivity tended to decrease; and in the case of ethylene-vinyl acetate co-polymer (EVA) and polyethylene (PE), as the density of the insulation materials increased, the thermal conductivity tended to also increase.