Roofing and roof coating specified for the UC Merced Library/Information Technology Center were confirmed by the manufacturer to have an emissivity of 0.9 (as well as the required Energy Star reflectivity). However, the design team recently discovered that the testing method used for determining the emissivity was ASTM C1371, rather than the ASTM E408 method that is referenced by LEED. According to the team\'s correspondence with a manager at the Cool Roof Rating Council (coolroofs.org), the use of the C1371 standard is very common; furthermore, the CRRC recognizes both of these ASTM testing methods as equivalent and accepts both methods\' emissivity data for inclusion in the CRRC\'\'s roof products rating directory. The CRRC also said that this issue has been brought to the attention of the relevant USGBC Technical Advisory Group for discussion. Please confirm whether the USGBC will accept the ASTM C1371 emissivity testing standard for roof products that have not undergone ASTM E408 testing.
ASTM C1371 will not be accepted in place of ASTM E408 to test emissivity. SSc7.2 CIR dated 12/15/2003 states that "To meet the requirements, 75% of the roofing material must meet both the reflectivity requirements of Energy Star based on testing using ASTM E903 and the 0.9 emissivity requirement based on ASTM E408 testing." The metrics used for this credit are currently being reviewed for potential revision in Version 2.2. Until a revised requirement is approved through USGBC membership ballot, the current credit language must be upheld." Please note that ASTM C1371-98 is used for determination of emittance of materials near room temperature, making it a more appropriate test method for the emissivity of interior materials such as foil and other reflective insulations. ASTM E408 measures total normal emittance of surfaces. ASTM itself states that "this Test Method (C1371) does not supplant