Horizontal Attic Radiant Barrier Installations
RIMA-I acknowledges the placement of a radiant barrier on top of mass insulation in attic spaces subject to the following conditions:
- The mass insulation and ceiling building materials should be checked for any evidence of moisture accumulation. Any existing moisture problem should be corrected before installing the radiant barrier.
- Radiant barriers used for this application must have a water vapor transmission per of at least five (5), as measured by ASTM E-96.
- Installation should be accomplished by laying the radiant barrier materials on top of the attic insulation without stapling or taping, so that it has very loose contact with the material below.
- Radiant barriers for this application should meet a Class A, Class 1 flame spread and smoke development rating as determined by ASTM E-84.
- The potential for contamination of the top surface by dust or dirt must be considered in specific applications where applicable.
- As with all building materials, local building codes should be considered.
This replaces the 1988 position paper on this application.

