Did you know how density impacts the performance of expanded polystyrene (EPS) foam?
Density describes the weight of materials within a given volume of foam.
EPS insulation is a rigid, closed-cell material formed by expanding and fusing polystyrene resin into a continuous structure. As more expanded polystyrene resin is incorporated into the same volume, the foam becomes denser. Density is typically expressed in pounds per cubic foot (pcf) and is calculated by dividing the weight of the EPS sample by its volume.
Higher density EPS contains more polymer and less air per unit volume, which generally results in increased strength, durability, and resistance to damage. Lower density EPS contains more air, making it lighter while still providing effective thermal insulation.
Density and EPS performance
There is a connection between density and the physical properties of EPS
Compressive Resistance |
Increases significantly as density increases |
R-value per Inch |
Increased slightly as density increases; remains relatively stable because EPS insulates primarily with air. |
Flexural Strength |
Increases significantly as density increases |
Water Absorption |
Decreases as density increases |
Dimensional Stability |
No impact with changes in density. |
Durability |
Increased resistance to product damage as density increases |
Please refer to ThermalStar TechData for complete details on the properties of ThermalStar EPS products.
