Unfaced insulation installed in wall cavities will do all of the following except:

Unfaced insulation installed in wall cavities will do all of the following except:

• A. Fire barrier
• B. Sound barrier
• C. Vapor barrier
• D. Reduce heat/cold transfer

Answer: (C)

Unfaced insulation is meant to slow heat flow and, to some extent, reduce sound transmission through wall cavities. It provides thermal resistance, so it helps keep interior temperatures steadier and can dampen sound between rooms. However, it does not function as a vapor barrier because there is no low-permeance layer to stop moisture diffusion. A vapor barrier requires a material specifically rated to block moisture movement, such as plastic film or certain faced insulations. Fire performance in walls comes from the overall rated assembly (not just the insulation), so unfaced insulation alone isn’t a formal fire barrier, even though it can contribute to fire resistance as part of the assembly.

Unfaced insulation is meant to slow heat flow and, to some extent, reduce sound transmission through wall cavities. It provides thermal resistance, so it helps keep interior temperatures steadier and can dampen sound between rooms. However, it does not function as a vapor barrier because there is no low-permeance layer to stop moisture diffusion. A vapor barrier requires a material specifically rated to block moisture movement, such as plastic film or certain faced insulations. Fire performance in walls comes from the overall rated assembly (not just the insulation), so unfaced insulation alone isn’t a formal fire barrier, even though it can contribute to fire resistance as part of the assembly.