Don F. Colvin describes the rooms used for ordinances in the attic story of the Nauvoo Temple.
Don F. Colvin, Nauvoo Temple: A Story of Faith (Provo, UT: Religious Studies Center, Brigham Young University, 2002), 221
Services in the Attic Story
The large central room as divided by canvas partitions was utilized in providing endowment ordinances to thousands of faithful Church members. The altar in Room 1 was used for numerous sealing ordinances and eternal marriages. There is indication that Rooms 2 and 4 were also used for some sealing ordinances. Side Rooms 11 and 12 were used for thousands of washing and anointing ordinances. Rooms 1 and 3 were also extensively used as offices.