Albert Barnes Commentary Ezekiel 41:15

"And he measured the length of the building before the separate place which was at the back thereof, and the galleries thereof on the one side and on the other side, a hundred cubits; and the inner temple, and the porches of the court;" — Ezekiel 41:15 (ASV)

The description of certain details is introduced by a summary statement of what had already been done.

Galleries - On either side of the eastern front of the building on the separate place, was a gallery of ten feet. Under this gallery was an approach to the building. Through this approach, refuse was to be carried in through openings in the north and south, and then carried out by a western postern.