Greg, I agree with you on the wicking issue however, the NM cable I see lately has no kraft paper anymore. So we are dealing with an outer plastic jacket and conductors that are not rated for wet or damp location. Conventional understanding is that the conductors are THHN/THWN but they are not marked that way on the jacket or on the conductors. The specs say only that they are to be rated for 90 degrees. and suitable for dry locations. So we are down to is the box set in the exterior wall facing the exterior of the building a dry location.
