An R-value measures the thermal resistance of a material. Meaning the R-value describes the property of the material to transfer thermal energy from one region to another.
In simple terms, the more R-values come in different types of foams and insulation materials, and the more effective they are at insulating a building. But, there are many types of R-values, and not all classes are equally effective in keeping buildings warm. To be sure that you are getting the best kind of material for your needs, you will need to know about the types of R-values of different types of materials and then compare them against each other to see which ones would be best for your building.
To get an idea of how effective the insulation is for specific types of R-values, you should first know the three types of R-values commonly used in insulation evaluations – surface-acoustic-wave (SAT), positive pressure-armature (PAT), and radiant barrier. Generally, these three types of R-values are used to measure insulation effectiveness. However, the surface-acoustic wave is the only type that is recommended for measuring insulation effectiveness.