In batt insulation, where must the moisture barrier be facing?

The correct placement of the moisture barrier in batt insulation is towards the heated side of the room. This orientation is crucial because the moisture barrier, often composed of materials such as polyethylene, serves to prevent moisture from seeping into the insulation from the interior of the home. By positioning it towards the heated space, it reduces the risk of condensation forming within the wall assembly, which can lead to mold growth, structural damage, and loss of insulation effectiveness.

When warm, moist air from the inside of a home rises and cools as it permeates through walls, it may condense if it encounters cooler surfaces. By having the moisture barrier facing the heated side, it restricts this moisture movement, ensuring that the insulation remains dry and effective.

Understanding this principle is key for home inspectors, as they must be able to identify proper insulation installation practices to mitigate potential issues related to moisture damage in walls.