Low temperature buildings used for food processing, storage and other applications create one of the most hostile environments to which insulation can be subjected. Such buildings, in order to serve their intended purpose, must maintain interior temperatures that are cool, sub-freezing, or even sub-zero. Under these conditions, it is critical that the building wall, roof and floor insulation possess superior water resistance qualities and stable reliable R-value. These are the attributes that make extruded polystyrene (XPS) the preferred insulation for low temperature buildings—an insulation that will endure the environmental demands while enabling the economical maintenence of a low temperature interior.
The constant low interior temperature in low-temp buildings creates moderate to high temperature differential and moderate to high vapor pressure differential between inside and outside. Temperature differences are the force that drives heat energy into the building, energy that must be removed via mechanical chilling equipment. Vapor pressure differences are the force that drives water vapor (humidity) into the building. The building insulation must be resistant to moisture absorption while under constant exposure to vapor intrusion due to vapor pressure differences between inside and outside.