Ezekiel 42:3-5

3Facing the twenty cubits that belonged to the inner court, and facing the pavement that belonged to the outer court, was gallery against gallery in three stories.

4And before the chambers was a passage inward, ten cubits wide and a hundred cubits long, and their doors were on the north.

5Now the upper chambers were narrower, for the galleries took more away from them than from the lower and middle chambers of the building.