The Conservatory (Room 21) features a new chequered marble floor, and it includes a small stairway. Large windows with all new materials throughout open up to the west courtyard. A small balcony in marble with iron balustrade, overlooking the courtyard, was added.

The wooden stairway between the two levels of the room has an iron balustrade. The entire floor structure is new, featuring iron beams and reinforced concrete with glass fan lights and iron bars. The floor consists of black and white marble tiles.