A soffit is an exterior architectural feature, generally the horizontal, aloft underside of the roof edge. Its archetypal form, sometimes incorporating or implying the projection of rafters or trusses over the exterior of supporting walls, is the underside of eaves (to connect a supporting wall to projecting edge(s) of the roof). The vertical band at the edge of the roof is called a fascia. A soffit of an arch is frequently called an intrados.