The Standard Houses are the oldest medianum apartments in Ostia, from the early Trajanic period (opus mixtum). On the ground floor four apartments can be recognized, in two blocks completely surrounded by streets. Only the streets to the north, east and between the two blocks were paved with basalt blocks. In the center of each set of apartments was an external, wooden staircase, leading to further apartments on the first floor. The medianum is flanked by two representative rooms. On one long side are two small rooms, presumably bedrooms. On the opposite side is the facade, presumably pierced by windows, that have not been preserved however. Each apartment had a kitchen and a latrine, marked L on the plan. Three of the four apartments have a door leading to the medianum. The medianum of the north-east apartment is the only one facing north-west. The south-east apartment has a door leading to a corridor next to the latrine.
There are a few scant remains of paintings and black-and-white mosaics.
Plan of the houses. After SO I.