A series of experiment for building thermal mass storage system was carried out using the real-scale experiment unit which can reproduce the real condition. The experimental condition varies direction of blowing, flow rate, installation density of diffuser and flow temperature in order to clarify their characteristics of charging and discharging thermal storage into the slab. The result shows that the rate of charge to the building materials including slab is between 70% from 80%. And uniformity of supply air blowing is effective for charging to the slab.
