What does R-Value measure?

R-Value is a measure of thermal resistance, specifically indicating how well a material insulates against heat transfer. The higher the R-Value, the more effective the insulation is at resisting the flow of heat. This means R-Value directly correlates with the material's ability to keep heat in during the winter and out during the summer, making it a crucial factor in evaluating insulation effectiveness.

Understanding R-Value is essential for making informed decisions about insulation materials in building projects. This measurement helps in assessing the energy efficiency of a structure; greater insulation resistance leads to lower energy costs and improved comfort levels within a space. Other options, while important in their own right, do not capture the primary function and significance of R-Value in evaluating insulation properties.