Active especially in Italy from the 1930s, he designed buildings such as the Watergate Complex in Washington DC, The Academy of Fencing, and Il Girasole ("The Sunflower") house, both in Rome.

[2][3] He was the natural son of Luigi Rolland (1852–1921), engineer and architect, born in Rome in a Belgian family, whose most important work is Teatro Adriano, and Maria Giuseppina Moretti.

[2][4] In 1929, Moretti graduated with honors, with a project for a college of higher education Rocca di Papa, where he won the Giuseppe Valadier award.

With this grant he worked with archeologist an art historian Corrado Ricci, in the arrangement of the areas east and north of Trajan's Market.

In these years he also worked as assistant for the professorships of Vincenzo Fasolo (architect of Mamiani Lyceum and Duca d'Aosta Bridge, both in Rome) and Gustavo Giovannoni, at the restoration chair.

In those years he participated in the competition for the construction of the Palazzo Littorio (Casa del Fascio), a project harshly criticized by the magazine Casabella and progressive Italian architectural culture in general.

The large building fronting the square was never finished, but after the war the structures already constructed were used for the "Skyscraper Italy (Grattacielo Italia)" by Luigi Mattioni.

He reappeared in 1945, was arrested for his collaboration with fascism, and was briefly imprisoned in the prison of San Victor, where he met count Adolfo Fossataro.

In 1958 Moretti participated with Adalberto Libera, Vittorio Cafiero, Amedeo Luccichenti and Vincenzo Monaco in the project of the Olympic Village in Rome designed for the XVII Olympiad scheduled in 1960.

Moretti was also general project coordinator for urban planning and design of the residential district "Quartiere INCIS Decima" in Zona Z. XXVII Torrino of Rome.

In 1963, he again won the award IN/ARCH 1963 for best achievement in the Lazio region with the study design of two twin buildings for Esso (Exxon) in the EUR in Rome.

In 1965, he began a fruitful relationship with the Consulting Group Le Condotte (later merged with Italstat), taking care of the design and implementation of resettlement Thermal Boniface VIII Fiuggi, the Metropolitana di Roma in the trunk by the Termini station to Via Ottaviano in Prati, opened in 1980.

[2][3][22][23] In 1967–1968, he won the Antonio Feltrinelli Prize's Accademia Nazionale dei Lincei[24] and got the task of designing a Tabgha sanctuary on Lake Tiberias on the Holy Land.

In 1971, he designed new buildings (with Vosbeck, Vosbeck, Kendrick & Redinger), for projects of General Real Estate, including the residential center in Alexandria, Virginia on the Potomac River, a residential center in Rocquencourt by Paris, in Montreal a new skyscraper as attachment to his previous 1961 realization of the Stock Exchange Tower (Tour de la Bourse).