This study investigated whether the combined use of rice hull and carbonized rice hull (CRH) can offset the negative aspects of each other, and can deliver an optimum indoor environment performance. To achieve this goal, the CO2 emissions of rice hull and the economic feasibility of CRH were considered simultaneously to deliver a mix ratio, and the fundamental properties of the material were analyzed to verify its performance. Full-scale mockups were constructed, and the effect on the indoor environment was verified through monitoring and a comparative analysis. Analysis showed that the heat capacity of the experimental mockup was larger than that of the control, and therefore it was effective in controlling indoor temperature in winter. The application of complex insulation material is also effective in controlling indoor humidity in winter and spring, and a humidity control plan that follows either a moisture-proof plan or ventilation is required to control humidity in summer and autumn. The CO2 level of the experimental mockup was high due to the anaerobic fermentation of the rice hull in the complex material. Therefore, a moisture prevention plan using water-proof and moisture-proof materials and a ventilation plan need to be considered in advance.