The aim of this study is to evaluate the actual insulation performance of the apartment building PC (precast concrete) envelope to which steel tying materials are additionally installed between structures and hollow-core slabs are applied. Through three-dimensional steady-state heat transfer simulation, the energy performance and condensation risk of each envelope composed of RC (reinforced concrete) and PC having the same legal U-factor and insulation method were compared and analyzed. As results, it was found that the effective U-factor and temperature difference ratio of the RC and PC envelopes were very similar, indicating that the energy performance and condensation risk were almost the same. The effective U-factor of both the RC and PC envelopes was about 30 to 90% higher than the legal U-factor, indicating a large heat loss due to thermal bridges. Therefore, in order to improve energy performance, it is necessary to remove thermal bridges in both the RC and PC envelopes.
- Precast concrete