EPS Insulation

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EPS Insulation

What is EPS Insulation?

EPS insulation is a rigid foam board made from expanded polystyrene, used for thermal insulation in walls, roofs, and foundations.

Description

EPS insulation, or expanded polystyrene insulation, is a rigid foam board insulation material made by expanding polystyrene beads with steam and molding them into panels. The result is a lightweight, closed-cell material with consistent thermal performance and moisture resistance.

In construction, EPS insulation is widely used in walls, roofs, foundations, and under concrete slabs. It is also a common component of insulated concrete forms (ICFs) and EIFS assemblies. EPS is valued for its durability, ease of handling, and ability to provide continuous insulation that reduces thermal bridging.

From a performance and code standpoint, EPS insulation offers stable R-values over time and performs well in below-grade and moisture-prone applications. Proper thickness, installation, and protection from UV exposure are important to ensure long-term effectiveness. EPS is recognized by building codes and is often used to meet or exceed energy code requirements.

FAQs

  • What is EPS insulation used for?

    It is used for thermal insulation in walls, roofs, foundations, and slab applications.

  • What does EPS stand for?

    EPS stands for expanded polystyrene.

  • Is EPS insulation water resistant?

    Yes, EPS resists moisture absorption and maintains insulation performance when exposed to water.

  • How does EPS compare to XPS insulation?

    EPS typically has a lower cost and stable long-term R-value, while XPS offers higher initial R-value per inch.

  • Is EPS insulation allowed by building code?

    Yes, EPS insulation is code-approved when installed according to manufacturer guidelines.

Fun Fact

EPS insulation is over 95% air by volume, which is what gives it its effective insulating properties.

CSI Code

07 21 00

NAHB Code

710