แนวทางในการปรับปรุงผนังอาคารเดิม เพื่อลดการถ่ายเทความร้อนเข้าสู่อาคาร / กัญจน์ พิเชษฐศิลป์ = A guideline for building wall system to improve thermal performance / Kan Pichetsilpa
The building wall is a part of building's covering that is directly and indirectly affected by sun radiation. This can cause higher temperature within the building. Therefore the building wall should be improved. There are many possible ways to improve the building wall system. The use of thermal insulation is one of the most interesting and easily applicable ways. Thermal insulation is used in the research. The masonry wall and the lightweight concrete wall, which have become popular in current construction techniques and will continue to be popular in the future are also studied. The purpose of this research is to find the ways of installing various sizes of thermal insulation in both types of test walls in the 4 directions. The buildings are air-conditioned building. The thermal variable ,the payback period and the life cycle cost are also considered in order to find out the walls' appropriate thickness and possibility. The research is divided into 2 parts: first, in order to selec the most appropriate thick,ness of thermal insulation 1,2 and 3-inch-wide thermal insulation is installed inside and outside the air-conditioned building in all 4 directions-north, east, west and south. Second, the most possible and appropriate way of installing thermal insulation is selected. The result indicates that thermal insulation helps reduce inside surface temperature swing. After thermal insulation is installed, the average temperature of the building throughout the day seems to be quite static Three-inch-wide thermal insulation is the most static. As for heat transmission, the research indicates that the inside and outside installation of 1,2 and 3-inch-wide thermal insulation can reduce heat transmission by 75%, 85% and 90%, respectively. Then, after considering payback period and life cycle cost, it was found that the 3-inch-wide thermal insulation is more cost effective than the 2 and 1-inch-wide since the 3-inch-wide thermal insulation has the shortest payback period (less than simple payback period 3.5 years). Three-inch-wide thermal insulation also has the most effective ability in reducing electricity rates. It has the lowest life cycle cost, as well. According to the research, thermal insulation installed outside the building wall is more suitable than the thermal insulation installed inside the building wall. Due to the nearly static temperature throughout the day and longer thermal time lag, inside installation can delay the heat transfer for 4 hours whereas outside installation can delay the heat transfer for 5 hours. This helps reduce heat transmission. The installation of the outside thermal insulation can also prevent thermal bridge and condensation will not occur. The building's area will still be used. It can be concluded that the most suitable way to improve the walls of the air-conditioned building is by utilizing the 3-inch-wide thermal insulation outside the building in all 4 directions in order to reduce heat transmission, condensation, and thermal bridge problems. This helps reduce the air-conditioning's cooling load as well. This result considered, the thermal insulation could be applied for all types of building walls.
