| Increasing the thickness of an insulating layer increases the thermal resistance. For example, doubling the thickness of fiberglass batting will
double its R-value, perhaps from 2.0 m²K/W for 110 mm of thickness, up to 4.0 m²K/W for 220 mm of thickness. Heat transfer through an insulating
layer is analogous to adding resistance to a series circuit with a fixed voltage. However, this only holds approximately because the effective thermal
conductivity of some insulating materials depends on thickness. The addition of materials to enclose the insulation such as sheetrock and siding
provides additional but typically much smaller R-value. |
