In Genesis, Noah’s Ark had three stories, or levels.
Genesis 6:16 gives instructions for the Ark’s design, mentioning a lower, second, and third deck. The vessel is therefore described as a multi-level structure rather than a single open boat. These levels would have provided separate interior spaces for Noah’s family, stored provisions, and the animals.
The biblical text does not provide a modern architectural plan or explain exactly how the decks were divided. Later paintings, models, and films have filled in those details imaginatively, so reconstructions can look very different from one another.
This fact is distinct from the Ark’s measurements. Genesis also gives its length, width, and height in cubits, but the three-story detail describes its internal arrangement. The account does not say that the Ark had engines, sails, or a rudder; its purpose was survival during the Flood, not navigation to a destination.