No. Use only unfaced fiber glass insulation with no vapor retarder. A facing acts as a vapor retarder, which helps reduce the amount of moisture entering a wall, ceiling, or floor. In heating climates, your original layer of insulation should already have a vapor retarder facing the "warm-in-winter" side (living area) of your home.
If you add a second vapor retarder with another layer of faced insulation, any moisture that does get through the first layer may condense on the second. This might cause water stains on the ceiling and could lead to severe structural damage.
Install the second layer of unfaced insulation perpendicular to the first, covering the wood ceiling joists to reduce heat loss through the wood. (NOTE: Apply the second layer of insulation perpendicular to the first layer only when the joist cavity is full. Otherwise, apply the second layer right on top of the first layer, between the joists.)


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