1 Kings 6:8

Then Hezekiah ordered them to prepare rooms in the house of Yahweh, and they prepared them.

And He built His sanctuary like the heights, Like the earth which He has founded forever.

“Go to the house of the Rechabites and speak to them and bring them into the house of Yahweh, into one of the chambers, and give them wine to drink.”

The side chambers were in three stories, one above another, and thirty in each story; and the side chambers extended to the wall which stood on their inward side all around, that they might be fastened, and not be fastened into the wall of the house itself.

The side chambers surrounding the house were wider at each successive story. Because the structure surrounding the house went upward by stages on all sides of the house, therefore the width of the house increased as it went higher; and thus one went up from the lowest story to the highest by way of the second story.