A fauces mosaic from Casa del Centenario (Pompeii).
The absolutely splendid wall decorations of the fauces leading into the Casa del Fauno (Pompeii).
It’s time to get to the point, what is an atrium house? This is a dilemma that have occupied historians for the last 300 years and there’s still not full consensus, thus a difficult matter to explain in a few short lines. I would summarize it as a type of upper class house that was in use between ca 300 Bc and 100 Ad. It should follow a certain plan, possibly not in detail but at least in general (a standardized plan of the atrium house).
The first room you would enter is the thin corridor that is normally called fauces (it was however not called fauces during antiquity). The word means “jaws” in Latin. This room would, as it gave any visitor a first impression, be decorated when possible and there are many so called facues mosaics preserved.