Thermal Insulator

Need a about 4mm thermal insulator for floor of a ripening room whose head space is limited. All sides of the room is 4" Polyurethane except the floor. The room operating temperature is between 13-20 deg. C.maintaining a 95% Relative Humidity.
The room is located in 15th floor of the building and we are worried of condensation at the 14th floor. The concrete floor slab is 8" thick.
Do we need to put an insulation or the 8" concrete floor slab is enough to prevent heat transfer to the 14th floor and avoid the condensation.

 

[TD2K]

There will always be a heat flow between the 14th and 15th floors unless they are at the same temperature. The key question is to answer your question, what is the range of temperatures at the 14th floor relative to the 13 to 20 C range you gave us?