In the urban mid layer office building, in order to construct 40m×40m open office space, large prestressed concrete slabs whose parts had vacancy layer and void had used. By using these vacancy layer and void as return air flow route on air conditioning mode and as thermal storage material on non-air conditioning mode, integrated system between structural material and air conditioning system was designed. Previously, indoor thermal environment and energy consumption of the system were evaluated using heat ventilation network calculation. In this report they are verified using BEMS and measurement equipment at the actual building
