Rigid Insulation: What Is It and How to Use It?

Rigid insulation, a type of thermal insulation, is primarily designed to resist heat flow and provide a protective barrier between the external environment and a building’s interior. Comprised of panels made from various materials, such as expanded or extruded polystyrene, polyisocyanurate, and fiberglass, rigid insulation offers a high insulation value with relatively thin materials.

Rigid polystyrene insulation panels loaded for delivery.

Primary Uses of Rigid Insulation:

  1. Wall Insulation: Rigid insulation panels can be applied to both the interior and exterior walls of a building. On exteriors, they provide continuous insulation that reduces thermal bridging and improves energy efficiency.
  2. Roof Insulation: For flat or low-sloped roofs, rigid insulation is an excellent choice. When installed above the roof assembly, it can protect the building from heat gain and loss, reducing energy consumption.
  3. Foundation and Slab Insulation: Installing rigid insulation beneath slabs or around foundations helps in preventing heat transfer between the ground and the building, ensuring more stable indoor temperatures.
  4. Basement Insulation: Rigid panels can be applied to basement walls to prevent the loss of heat and reduce the risk of moisture-related problems.
  5. Cavity Wall Insulation: Rigid insulation can be inserted into wall cavities to increase a wall’s thermal resistance.
  6. Soffit and Eave Insulation: In areas where there’s a risk of moisture accumulation, rigid insulation provides both insulation and a moisture barrier.

Benefits of Rigid Insulation:

  • High R-Value: Rigid insulation typically offers a higher R-value (thermal resistance) per inch compared to other forms of insulation.
  • Moisture Resistance: Many types of rigid insulation are water-resistant, making them ideal for places prone to moisture.
  • Durability: Rigid insulation panels are less susceptible to damage and can last for a long time without degrading in performance.
  • Ease of Installation: With their firm and sturdy nature, these panels can be easily cut to fit various spaces and can be quickly installed.

Rigid insulation is a versatile and efficient solution for various insulation needs in construction. Its diverse applications and benefits make it a popular choice among builders and homeowners aiming for energy efficiency and protection against the elements.

Types of Rigid Insulation We Have:


Closed-cell, rigid foam board insulation that is faced with either a composite material, or foil. Polyiso insulation is very thermally efficient. LTTR-values for polyiso insulation can range from 6.0 to 6.5 per inch. Its High R-value, leads to improved energy efficiency.


Closed cell, moisture-resistant rigid foam board for a wide variety of building applications XPS foam panels are typically used for below-grade applications such as foundations, beneath slabs, and below grade environments where moisture can be present.  Superior stable insulating properties, regardless of moisture content.


Expanded polystyrene is a rigid and tough, closed-cell foam. It is usually white and made of pre-expanded polystyrene beads. Sheets are commonly packaged as rigid panels, which are also known as “bead-board”. Closed-cell panels, provides a lightweight panel, with minimal moisture absorption and low vapor permanence. A more economical option compared to XPS.

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Our inventory is very diverse. Please contact us for your specific needs.