A material with a higher R-value is a better insulator.
The R-value is a measure of a material’s (such as a layer of insulation) resistance to conductive heat flow. Materials with higher R-value indicate better insulating properties or effectiveness. Certain factors such as the thickness, density and the type of insulation determine the R-value of most materials while for some insulation, it is also determined by aging, temperature and moisture accumulation.
