Foams :

Polystyrene foams are good thermal insulators so frequently can be used as building insulation materials, same as insulating concrete forms and structural insulated panel building systems.
Polystyrene incorporating graphite has superior insulation properties.
They are also used for non-weight-bearing architectural structures (such as ornamental pillars).
PS foams also show good damping properties; so it is can be used widely in packaging process.

Extruded closed-cell polystyrene foam is sold under the trademark Styrofoam .
This method is frequently used informally in North America for other foamed polystyrene products.