This is a very plain building that evidently had a utilitarian function. It consisted of barrel-vaulted rooms on two levels placed around a rectangular courtyard paved in opus spicatum. A wooden balcony connected the rooms of the second story. Off the courtyard on the southwest side was a large 15-person latrine. The building may have provided housing for the service staff, store rooms for equipment and supplies, or both. The building dates to Phase I (118-125 CE).