The cornice of a building very often does duty as a gutter also.

A wooden cornice gutter, sometimes called a box gutter, as shown in Fig. 34, is employed in the construction of the better class of framed buildings. The carpenter completes the cornice and forms the bottom of the gutter with the proper grade. The tinsmith then lines the gutter before the shingles or slates are laid. The lining, like those in Figs. 32 and 33, is nailed to the roof and over the front edge of the gutter with a blind edge, as shown.

Sheet-metal cornice gutters are constructed on the same general principle.