This study develops a hybrid triple glazing technology that combines vacuum and carbon dioxide (CO2) gaps to help store CO2 in buildings. We determine the optimal thickness of glazing and calculate its thermal transmission (U-value). The amount of energy saved by using the proposed glazing system is then compared with that when using conventional insulating gases (air, argon, and krypton). Therm & Window, a modeling and analysis program for glazing, and EnergyPlus, a building environment and energy evaluation program, were used for the analysis. The optimal thickness determined for the vacuum and CO2 sections is 6.2 mm and 19 mm, respectively. The latter section comprises a 15-mm CO2 gap and 4 mm of glass. The total thickness of the glazing is 25.2 mm and the U-value is 0.259 W/m2ĚK. The energy performance of the triple glazing using vacuum and CO2 gaps is between that of glazing using vacuum and air and that using vacuum and krypton gas gaps. Further, its performance is comparable to that of triple glazing using vacuum and argon gas gaps. Therefore, the hybrid triple glazing proposed in this paper represents an advanced glazing technique that can absorb CO2 and reduce energy consumption in buildings.