Ezekiel 42:7-9
42:7 As for the outer wall by the side of the chambers, toward the outer court facing the chambers, it was 87½ feet long.
42:8 For the chambers on the outer court were 87½ feet long, while those facing the temple were 175 feet long.
42:9 Below these chambers was a passage on the east side as one enters from the outer court.