• Journal of the Korean housing association
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• v.22 no.1
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• pp.115-122
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• 2011

This study aimed at quantifying the impact of envelope insulation on energy consumption for thermal controls in residential buildings in southern part of Korea. A series of parametric simulations for a range of R-values of walls, roof, floor, and windows were computationally conducted for a prototypical Korean detached house. Analysis revealed that the total amount of heat gain was larger than that of heat loss, while the amount of energy for cooling was smaller than that for heating due to the difference of system efficiency; the envelope heat transfer was more significant for the heat loss, thus, the increase of the envelope insulation was more effective to reduce heating load; and there were certain levels of envelope insulation after which the energy saving effect was not significant. These findings are expected to be a fundamental database for the decision of proper insulation level in Korean residential buildings.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.5
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• pp.372-381
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• 2003

This study aims to find out the optimized insulation thickness of refrigerated warehouse with different envelope structures (RC and PC wall) and insulation materials (urethane and icynene). Each of them is compared according to the thickness of insulation (100, 150, 200 mm/50 or 250 mm) and the temperature of cold storage room (0, -6, -15$^{\circ}C$). As results, it is proved to have the best economical efficiency in life cycle cost when PC wall with thickness of 100 mm (0 and -6$^{\circ}C$) and 150 m (-15$^{\circ}C$) urethane, respectively, are applied.

• KIEAE Journal
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• v.16 no.1
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• pp.5-10
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• 2016

Purpose: The energy consumption in buildings has continuously increased in some countries and it reaches almost 25% of the total energy use in korea. Therefore there are various efforts to minimize energy consumption in buildings, and the regulations on building envelope insulation have been tightened up gradually. To satisfy the building regulation, the use of vacuum insulation panels(VIPs) is increasing. VIP is a high performance insulation materials, so that it can be thinner than conventional insulation material. When VIP is applied in a building, it may cause thermal bridge, which occurs due to very low thermal conductivity compared to other building materials and the envelope of VIPs. Method: This study designed the capsulized VIPs using conventional insulation for reduction of the thermal bridge. Then designed VIPs were applied to a wall. The linear thermal transmittance and the effective thermal conductivity were analyzed by HEAT2 simulation program for two dimensional steady-state heat transfer. The result compared with a wall with non-capsulized VIPs. Result: It analyzed that the wall with capsulized VIPs had lower linear thermal transmittance and reduced the difference of the effective thermal transmittance with one dimensional thermal transmittance compared to that of the wall with non-capsulized VIPs.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.6
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• pp.153-164
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• 2019

The presence of thermal bridges in a building envelope cause additional heat loss which increases the heating energy. Given that a higher building insulation performance is required in these cases, the heat loss via thermal bridges is a high proportion of the total heat energy consumption of a building. For the dry exterior insulation system that uses mullions and transoms to fix insulation and exterior materials such as stone and metal sheet, the occurrence of thermal bridges at mullions and transoms is one of the main reasons for heat loss. In this study, a dry exterior insulation system using the truss insulation frame (TIF) was proposed as an alternative to metal mullions. To evaluate the building envelope performance, structural, air-leakage, water-leakage, fire-resistance, thermal, and condensation risk tests were conducted. In addition, the annual energy consumption associated with heating and cooling was calculated, including the linear thermal transmittance of the thermal bridges. As a result, the dry exterior insulation system using TIF achieved the allowable value for all tests. It was also determined that the annual heating load of a building was reduced by 36.7 % when the TIF dry exterior insulation system was used, relative to the dry exterior insulation system using steel pipes without additional insulations.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.2
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• pp.89-95
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• 2017

This study aimed to compare the primary heating energy consumption of regional apartment houses based on the enhanced thermal insulation performance of building envelope standards. The difference of the heating energy consumption based on the enhanced thermal insulation performance of building envelope standards in the southern region, the largest regional difference in primary heating energy consumption, is $10.3kWh/(m^2{\cdot}year)$. The difference of the heating energy consumption based on the enhanced thermal insulation performance of building envelope standards in the central region is $8.0{\sim}8.5kWh/(m^2{\cdot}year)$ and that of the Jeju region is $0.5kWh/(m^2{\cdot}year)$. These energy consumption differences do not result in building energy efficiency ratings changing. The building energy efficiency ratings have the possibility to be changed.

• KIEAE Journal
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• v.12 no.6
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• pp.85-92
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• 2012

The Korean government has introduced building regulations with improved energy conservation measures, including higher insulation levels for building envelope. However, there are many existing buildings that tend to consume more energy for heating and cooling than new buildings, as they were built under the former regulations with relatively higher U-values of walls and glazing. In order to improve energy efficiency in existing buildings, green remodelling of building envelope and building services are required. For existing buildings, building services improvements have been achieved through energy service company(ESCO), but much attention has not been paid to building envelope improvements with various reasons, such as uncertainty of energy saving effect design issues and costs. The aim of this study is to evaluate the impact of building envelope improvements in a typical commercial building on its heating and cooling energy loads. The results show that the improvement of glazing with lower U-values has the highest energy saving effects, followed by wall, roof and floor, under the condition of same level of insulation improvements. However, high insulated glazing increased LCC because of higher initial investment costs.

• KIEAE Journal
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• v.5 no.1
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• pp.27-33
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• 2005

Global efforts have made to reduce energy consumption and $CO_2$ gas emission. One of the weakest parts for energy loss through the whole building components is building envelopes. Lots of technologies to increase the thermal performance of building envelopes have been introduced in recent year. Transparent Insulation Wall(TIW) is a new technology for building insulation and has been function both solar transmittance and thermal insulation. A mathematical model of a Transparent Insulation Wall equipped with south wall was proposed in order to predict thermal performance under varying climates(summer and winter). Unsteady state heat transfer equations were set up using an energy balance equation and solved using Gauss-Seidel iteration solution procedure. The thermal performance of the TIW determined from a wall surface and air layer temperature, non-airconditioned room temperature and air conditioning load. As a result, this numerical study shows that the TIW is effective in an air conditioning load reduction. Further experimental study is required to establish complete TIW system.

• KIEAE Journal
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• v.13 no.2
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• pp.53-60
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• 2013

This study examined the building envelope structure used in small housings near urban area which have not good energy source in relation to the application of passive design for energy saving of small-sized architectural design firms in local cities and aimed to provide the basic materials of future design direction of designers and housing owners by analyzing economy of a project in order to know the amount of energy saving and additional expenses depending on the building envelope pattern. As a result of comparing and examining the energy saving cost from the period of use compared to investment by the thickness of insulating materials based on building envelope pattern for energy saving, it was found that the thicker the insulating materials are, the more energy saving amount is. While the current bead-type insulating materials have short payback period due to low initial investment, extruded insulating materials show the difference of five years compared to bead-type insulation because of its high initial investment.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.846-856
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• 2017

The aim of this study was to develop the details of cross-laminated timber (CLT) envelops for satisfying the design standard for energy saving (DSEA) and passive standard in South Korea. When the same thickness of 180 mm concrete or CLT was used and the same materials for other layers were used for the roof, wall, and interlayer floor, the required insulation thickness for the different building envelopes in central, southern, and Jeju island was evaluated. As a result, compared to the concrete envelop, about 43 mm of insulation thickness was reduced for wall and roof with the CLT envelope. When the CLT envelopes were modified to protect the CLT from moisture based on FPInnovations (2011), the insulation thickness was further reduced by 12 mm. When the modified CLT building envelops satisfied with a passive standard are used for 10-story building, the required insulation was decreased by $40.89m^3$ for a floor ($105.27m^2{\times}2.3m$ in height) compared to concrete building. As the number of floors increases, about 3.58 m3 of insulation per floor was additionally saved.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.11
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• pp.1156-1164
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• 2001

This study aims to suggest envelope structure which can improve the insulation performance of cold storage warehouse with cost effectiveness. Envelope structures are classified and economical efficiency of each type is evaluated to the model warehouse. As results, type 3 (PC wall) and 4(sandwich panel wall) have benefits to the middle/large (lifetime of 25 years) and small (lifetime of 12∼13 years) warehouse, respectively.