Expanded Polystyrene (EPS) is a lightweight, closed-cell insulation material widely used for its excellent thermal insulation and cost-effectiveness.
One of the key properties that defines the long-term performance of EPS in various applications is its dimensional stability. Dimensional stability refers to the ability of EPS to maintain its original dimensions when subjected to environmental factors such as temperature changes and humidity.
To ensure EPS products can withstand temperature and humidity changes without excessive dimensional change, dimensional stability is tested according to ASTM D2126, “Standard Test Method for Response of Rigid Cellular Plastics to Thermal and Humid Aging”.
Materials are tested for 7 days under the following conditions:
- 158°F (70°C) and 97% RH
- -40°F (-40°C) and ambient RH
Atlas’ ThermalStar® insulation meets the dimensional stability requirements contained within the industry standard ASTM C578, “Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation”.
