"A private toilet cubicle was very rare in antiquity, and to date, only a few have been found, mostly in the City of David," said Billig in a statement.
"Only the rich could afford toilets. In fact, a thousand years later, the Mishnah and the Talmud discuss the various criteria that define a rich person, and Rabbi Yossi [suggests that] to be rich is [to have] a toilet near his table.'"
IAA director Eli Eskisiod said it was fascinating to consider how something so common today would be considered a luxury to people during the reign of the kings of Judah.
Leaving no stone unturned, the team also dug into the septic tank and found several animal bones and pottery.
The study of such objects and materials could help shed light on the diet, lifestyle and diseases of people living during this period.
Further afield from the toilet, archaeologists also found evidence of a garden that had ornamental trees, fruit trees ad aquatic plants. These findings supposedly add to the impression that a well-off family had resided at the estate.
According to Billig, the estate may have been a residence of a king of Judah,
In March, dozens of pieces of a Dead Sea Scroll containing biblical text were discovered in the Judean Desert by archaeologists.
It had been around 60 years since the last fragments of the Dead Sea Scrolls had been found, in a cave where Jewish rebels had hidden from the Roman Empire around 1,900 years earlier.
The team from IAA plan to present their findings at the conference taking place in Jerusalem this week called "Innovations in the Archaeology of Jerusalem and its Surroundings."