The 1950s restoration of the Sala delle Asse was part of a larger project for the refurbishment of the Castle museums. Costantino Baroni, the then acting director of the Civic Museums of the Sforza Castle, awarded the job to a group of architects known as BBPR (Gian Luigi Banfi, Lodovico Barbiano di Belgioioso, Enrico Peressutti, Ernesto Nathan Rogers).

Works in the hall began in 1954 with the removal of the wallpaper and wooden benches designed by the architect Luca Beltrami. With their removal, traces of a preparatory drawing in monochrome on the north and west walls reappeared. In 1955 Ottemi della Rotta was commissioned with restoring the painted decoration, a complex task given Rusca’s previous restoration, which had completely covered the original late 15th century decoration.

Ottemi della Rotta opted to keep the scheme adopted in 1901, only softening the intense colours used by Rusca so as to give the decoration an antique and abraded quality.

Della Rotta left a few sheets of drawing paper on the lunettes, as testimony to the type of restoration carried out, and on which were painted the result of the work. Under these, to this day, remain well preserved sections of Rusca’s restoration.