Active comfort controlled bedding systems

A process for changing a firmness property of a viscoelastic foam layer in a mattress assembly, the process comprising:

• providing the mattress assembly with at least one viscoelastic foam layer having a first glass transition temperature greater than 60° F. at 0% humidity, and a second glass transition temperature less than the first glass transition temperature at a % humidity greater than 0, the at least one viscoelastic foam layer comprising a phase change material stratified in a foam structure of the at least one viscoelastic foam layer;
• and
• heating the at least one viscoelastic foam layer comprises heating above the second glass transition temperature and below the first glass transition temperature to alter the firmness property, wherein heating the at least one viscoelastic foam layer comprises generating heat from a thermoelectric fabric comprising layered p-n junction material laminated into a fabric structure underlying the at least one viscoelastic foam layer, wherein the heating is controlled by a feedback system responsive to a plurality of sensors measuring at least a humidity condition and a temperature condition about the at least one viscoelastic foam layer and changing at least one of the humidity condition and temperature condition to alter the firmness of the viscoelastic foam layer.