The R-value per inch of blanket insulation, commonly made from fiberglass, typically ranges from R-2.9 to R-3.8.
Understanding Blanket Insulation R-Values
The R-value is a measure of thermal resistance, indicating how well an insulation material resists the conductive flow of heat. A higher R-value signifies better insulating performance. For blanket insulation, which includes batts and rolls, the overall R-value of a product depends directly on its thickness.
Factors Influencing R-Value
While the per-inch R-value offers a general guideline, the actual insulating performance can be influenced by several factors:
- Material Density: Denser fiberglass insulation tends to have a slightly higher R-value per inch within the typical range.
- Installation Quality: Proper installation without compression, gaps, or voids is crucial to achieving the rated R-value.
- Temperature: R-values can slightly vary with the temperature differences across the insulation.
Typical R-Values for Blanket Insulation Thicknesses
To illustrate how the per-inch R-value translates to overall insulation performance, consider these common examples for fiberglass blanket insulation:
| Insulation Thickness | Approximate Total R-Value | Implied R-value per Inch |
|---|---|---|
| 3 ½ inches | R-11 | ~R-3.14 |
| 12 inches | R-38 | ~R-3.17 |
These examples demonstrate how the total R-value increases proportionally with the thickness of the blanket insulation. When selecting insulation, it's important to consider the recommended R-value for your specific climate zone and the area being insulated, such as walls, attics, or floors.
For more general information on insulation and R-values, you can refer to resources from the U.S. Department of Energy.
