What Is the Right Insulation for an Attic: Faced or Unfaced?

Loose Fill

• The most common attic insulation is loose fill, which has no facing. It consists of granules or pellets of cellulose, fiberglass, wool or some mineral or slag. It is generally blown in with air pressure and is typically installed during construction. As the name implies, it is loose, piled between roof joists and in cavities at the attic edge.

Rolls or Batts

• An option for attic insulation is rolls or batts, usually made of fiberglass although rock wool and natural fibers may be used in some types. The standard roll or batt insulation, however, is fiberglass, formed into sheets to fit between roof joists. This may be installed initially but usually is added on top of blown-in insulation for additional coverage.

Faced

• Faced fiberglass rolls or batts may be used in initial installation. The facing is a vapor retarder, which will reduce moisture penetration into a ceiling. The facing should be installed down, with the fiberglass side up. Fiberglass roll or batt insulation as a first layer should be laid between roof joists.

Unfaced

• Always use unfaced rolls or batts when adding insulation in an attic. Never install two vapor or moisture barriers. You can buy unfaced fiberglass insulation or use existing rolls or batts by peeling off the paper layer. Install rolls or batts as second-course insulation across the joists. Never place rolls or batts on top of loose fill insulation, where it might depress or condense the loose fill and reduce its insulating efficiency.