somewhere between 90 and 99.8% porosity. Aerogels have a porous solid network that contains air pockets, with the air pockets taking up the majority of space within the material.

Aerogels are good thermal insulators because they almost nullify two of the three methods of heat transfer - conduction (they are mostly composed of insulating gas) and convection (the microstructure prevents net gas movement). They are good conductive