The real estate industry takes an important part in social daily life. Generally, real estate portal agents only provide limited information that would not suit the increasingly complex requirements of customers. In this paper we propose a method to measure parameters like thermal diffusivity and noise proof to evaluate real estate properties. We have been developing IoT sensor systems for this real estate evaluation. With our IoT sensor system, we measured multiple environmental data in 109 apartments in main cities across Japan. Based on the data, we quantified the performance of thermal diffusivity and noise proof.