All about an Insulation Products R-Value

The R-Value of an insulation product such as spray foam, measure how heat resistant the insulating material is. This may also be called the materials thermal resistance. The R-value depends on the type of material and is measured per inch. To determine the R-Value of an insulating material, experts at the American Society of Testing and Materials perform a series of rigorous tests. Factors that help determine the R-Value include the materials type and thickness.

Insulating Materials and their given R-Values:

• Closed-Cell Polyurethane Spray Foam: 6.3
• Open-Cell Polyurethane Spray Foam:   3.9
• Cellulose Wall Spray:  3.8
• Dense-Pak Cellulose:   3.8
• Blown-in Cellulose:     3.7
• Fiberglass:      3.2
• Cotton Fiber:  3.2

Keep in mind, R-Values are based and tested in an absolute zero wind and a zero moisture environment. These are not real life circumstances therefore the R-Value of insulating materials can be misleading. Please consult professionals like the ones at Virginia Foam, to get an expert’s opinion on the type of insulation perfect for your home.