If building material R-values or thermal conductivities are determined by testing, one of the following test procedures shall be used:
- ASTM C 177
- ASTM C 236
- ASTM C 518
For concrete, the oven-dried conductivity shall be multiplied by 1.2 to reflect the moisture content as typically installed.
If assembly U-factors are determined by testing, ASTM C 1363 shall be used. Product samples tested shall be production line material or representative of material as purchased by the consumer or contractor. If the assembly is too large to be tested at one time in its entirety, then either a representative portion shall be tested or different portions shall be tested separately and a weighted average determined. To be representative, the portion tested shall include edges of panels, joints with other panels, typical framing percentages and thermal bridges.