Imbrex and tegula

In Rome, they replaced wooden shingles, and were used on almost every type of structure, from humble outbuildings to grand temples and public facilities.

Like bricks, they were formed of wet clay in a four-sided mould, often shaped with a piece of wire, and then baked in an oven or kiln.

[citation needed] Tegulae were originally made perfectly flat, or with nothing more than a ridge underneath the upper border, which allowed the tile to be "hung" upon a sloping roof so that it would not slide to the ground.

In formal architecture the canalis had a plain or ornamented frontal piece set atop the entablature, immediately above the cornice.

The semicircular opening at the front of the lowermost imbrex was often capped with an ornamental fronton, and the spouts which drained the gutters were frequently decorated with lions' heads (capita leonina) or other fantastic or grotesque faces.