A
soffit is the horizontal underside of a roof overhang, an archway, a staircase,
a ceiling or a similar architectural component. From the Italian soffitta for
under and figgere, to fix, the word soffit dates back to early Palladian
architecture. Typical soffits on today's houses include the flat area under the
eaves where vents provide attic ventilation; the lower perimeter of a drop
ceiling; and the ceiling mounted to the underside of a staircase.