• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.801-806
• /
• 2008

The best plan is that the insulation performance should be improved because the insulation and airtight of building envelopes have an effect on the energy consumption basically. New insulation materials, which have the high performance and are above insulation standard, have been developed steadily. Because there are not studies on the building energy rating system and economic evaluation considering new insulation materials, these matters should be studied. In result alternatives, which applied 6 high performance material each, influence, reduce the annual heating energy and raise the building energy rating. Applying the vacuum insulation material(Case1,2) and vacuum or triple glazing can retrieves the investment with $120 and $$140{\sim}150$ per barrel each.

• Solar Energy
• /
• v.15 no.3
• /
• pp.119-125
• /
• 1995

Since the using of heating energy associated with infiltration is significant in a building, the efforts to minimize the infiltration while ensuring minimum ventilation rates for various types of occupancy will be beneficial. In constrast to that many efforts have been made to reduce heat loss by improving thermal resistance of building envelope, little has been tried to reduce heat loss from infiltration. For achieving such an objective, measurement of air leakage rate will be pre-requisite as a diagnostic tool. A blower door system, a depressurization/pressurization method, was employed and it demonstrated a good potential for measuring airtightness performance of residential buildings. Based on the test results, annual energy savings for residential heating was estimated by reducing infiltration to a level of reasonably airtight or to a level of ASHRAE Standard 62-1989 for minimum ventilation.

• Journal of the Korea Institute of Building Construction
• /
• v.16 no.1
• /
• pp.9-15
• /
• 2016

The part of a building with the biggest energy loss is the exterior and many studies are actively conducted to reduce the energy loss on that part. However, most studies consider the window frames and insulation materials, but many studies do not discuss the concrete that takes more than 70% of the exterior. In order to minimize the energy loss of buildings, it is necessary to enhance the concrete's insulation performance and studies need to be conducted on this. Therefore, this study used a micro foam cell admixture, calcined diatomite powder, and lightweight aggregates as a part of a study to develop a type of concrete with improved insulation performance that has twice higher thermal conductivity compared to concrete. It particularly secured the porosity inside concrete to lower thermal conductivity. As a result of the experiment, the slump and air capacity showed fair results, but all mixtures containing micro foaming agent showed 14.3~35.1% lower mass per unit of volume compared to regular concrete. Compressive strength decreased slightly due to the materials used to improve the insulating performance, but it all satisfied this study's target strength(24MPa). Thermal conductivity was up to twice higher than that of regular concrete.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.39.2-39.2
• /
• 2011

The new and renewable energy today has a great interest in all countries around the world. In special it has need more limit of the fossil fuel that needs of low carbon emission among the social necessary conditions. Recently, the high-rise building demand the structural safety, the economic feasibility and the functional design. The high-rise building spends enormous energy and it satisfied the design in solving energy requirements. The requirements of energy for the building depends on the partly form wind energy due to the cladding of the building that came from the surroundings of the high-rise building. In this study of the wind energy, the cladding of the building was assessed a tentative study. The wind energy obtains from several small wind powers that came from the building or the surrounding of the building. In making a cladding the wind energy forms with wind pressure by means of energy transformation methods. The assessment for the building cladding was surrounded of wind speed and wind pressure that was carried out as a result of numerical simulation of wind environment and wind pressure which is coefficient around the high-rise building with the computational fluid dynamics. In case of the obtained wind energy from the pressure of the building cladding was estimated by the simulation of CFD of the building. The wind energy at this case was calculated by energy transform methods: the wind pressure coefficients were obtained from the simulated model for wind environment using CFD as follow. The concept for the factor of $E_f$ was suggested in this study. $$C_p=\frac{P_{surface}}{0.5{\rho}V^{2ref}}$$ $$E_c=C_p{\cdot}E_f$$ Where $C_p$ is wind pressure coefficient from CFD, $E_f$ means energy transformation parameter from the principle of the conservation of energy and $E_c$ means energy from the building cladding. The other wind energy that is $E_p$ was assessed by wind power on the building or building surroundings. In this case the small wind power system was carried out for wind energy on the place with the building and it was simulated by computational fluid dynamics. Therefore the total wind energy in the building was calculated as the follows. $$E=E_c+E_p$$ The energy transformation, which is $E_f$ will need more research and estimation for various wind situation of the building. It is necessary for the assessment to make a comparative study about the wind tunnel test or full scale test.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.28 no.5
• /
• pp.511-521
• /
• 2015

The thermal bridge occurring in a building influences its thermal performance and durability. The domestic typical multi-unit residential buildings suffer thermal losses resulting from thermal bridges of the balcony slab. To minimize the thermal loss between inside and outside of the balcony slab, thermal bridge breaker(TBB) systems have been developed and applied in building construction. Although thermal bridge breaker systems for reinforced concrete(RC) wall-slab joints can improve the thermal performance of a building, it is necessary to verify the structural performance of TBB systems whether they provide proper resistance for cyclic loading. In order to investigate the structural characteristics of TBB systems embedded in RC slabs, cyclic tests of wall-slab joints were performed by applying two reversed cycles at each up to 30 cycles. The test results show that the RC slabs embedding TBBS systems can present excellent structural performance and the maximum moment capacity, energy dissipation capacity and ductility of TBBs systems are enhanced compared to those of the typical RC slabs.

• KIEAE Journal
• /
• v.11 no.6
• /
• pp.139-149
• /
• 2011

This study focuses on design tendencies in office buildings of public institutions after tightening up Korea's building energy performance criteria. Important office design criteria and recommendations pay attention to the issues such as building orientation, greening buildings, building form, space and envelop by intensifying building energy performance related laws, government guidelines and evaluation systems. The design tendencies explored in this research are as follows. Office buildings mainly face south and have various types of indoor and roof green spaces not for ecological reasons but for the rest. Building depth becomes thinner and atria are inserted into office buildings to improve daylighting and natural ventilation. Building cores are located on north or west and east sides acting as buffer spaces to reduce heat loss and to block solar radiation. Office building envelop design includes various creative ideas to control or utilize solar energy as like three dimensional or double structured skin and window size variation to cope with the intensity of solar radiation. Further, solar energy generation systems are integrated with building component such as roofs, sun screens and windows. This study demonstrates that government's reinforcement of the building energy performance criteria drives the change in design methods and approach.

• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.857-862
• /
• 2008

Window is the most demanding design component in the building design. Recently, window area in the building surface has been increased significantly in the office building. As window area increased significantly, however, the thermal load has been increased significantly due to lack of thermal performance of the outside wall. In this paper, we discussed the energy consumption of the buildings according to window area ratio. Two types of building for energy consumption analysis were made by Designbuilder v.1.4 and Energyplus v.2.0. Window area ratio was five different types ($30%{\sim}70%$) in each building. As a result, the cooling energy consumption has been decreased as window area decreased in each building. Whereas the heating energy consumption has been increased window area decreased.

• Journal of the Korean Solar Energy Society
• /
• v.26 no.1
• /
• pp.81-89
• /
• 2006

Building integrated photovoltaic (BIPV) system operates as a multi-functional building construction material. They not only produce electricity, but also are building integral components such as facade, roof, window and shading device. On the other hands lots of architectural considerations should be reflected such as Installation position, shading, temperature effect and so on. As PV modules function like building envelope in BIPV, combined thermal and PV performance should be simultaneously evaluated This study is on the combined thermal and PV performance evaluation of BIPV modules. The purpose of this study is to investigate a temperature effect of PV module depending on the ventilation type of PV module backside. Test cell experiment was performed to identify the thermal and power effect of PV modules. Measurement results on the correlation of temperature and power generation were obtained. Those results can be utilized for the development of optimal BIPV installation details in the very early design stage.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.25 no.2
• /
• pp.49-54
• /
• 2013

In field of apartment housing currently, insulation technology is the most effective way because it is common to improve the thermal performance, therefore, it is contributed to energy saving as several regional insulation standards and legal mandate method. In addition, by applying of building energy efficiency rating certification system, it has inspired voluntary energy conservation commitment for the building owner or facility manager by making a plan to evaluate and verify building energy performance. However, these circumstances are not enough to acquire a grade 2 of higher information. Therefore, in this study, we analyzed the impact of building energy efficiency rating and confirmed reduction ratio compared to the standard housing on the basis of recent our nation building law when we had changed the shape of windows and wall insulation performance and shapes of housing.

• Journal of the Korean Wood Science and Technology
• /
• v.43 no.6
• /
• pp.876-883
• /
• 2015

Han-green project, which pursues Korean style post and beam timber house with traditional construction technique of Han-ok, has been carried out in KFRI (Korea Forest Research Institute) since 2006. Recently, the improvement of its building energy performance was studied with energy-saving elements. This study was conducted to provide the insulation details of building envelopes in a post-beam timber house for recent enhanced insulation standards and following effect on building energy performance. The level of thermal transmittance (U-value) values of building envelopes was composed of two stages: present Korean insulation standards and passive house. To evaluate building energy performance, the building airtightness values of two stages was ACH50 = $3.0h^{-1}$ for common domestic timber house constructed recently, and ACH50 = $0.6h^{-1}$ for passive house. Consequently, four cases of the building energy performance according to the combination of U-value with airtightness were evaluated. The test house for evaluation was located in Seoul and its energy performance was evaluated with CE3 commercial building energy simulation program. The result showed that enhanced insulation from level I to II reduced $14kWh/(m^2{\cdot}a)$ of annual heating energy demand regardless of airtightness.