In contemporary sources, Sardi is described more often as acting in the capacity of a capomastro or master builder rather than as an architect. He designed and executed only one church from scratch, that of Santa Maria del Rosario in 1712 in the Colonna family fiefdom of Marino, in the Alban Hills outside Rome. The interior is centrally planned and has an unusual and elaborately decorated dome. This is also his first known work. His work as capomastro is documented on the building sites of Santa Maria in Trastevere, Santa Maria in Monticelli and at Santissima Trinità dei Pellegrini. Sardi is also credited with one other minor work, the refurbishment of the baptistery of San Lorenzo in Lucina, executed between 1713 and 1721. Although Sardi's name has been connected with several churches in and around Rome, one of the mostly securely attested of his commissions is the addition of a new façade to the church of Santa Maria in Cosmedin in the Foro Boario in Rome. This façade was erected in place of the previous Romanesque façade in 1718, and destroyed in 1896 – 1899 but its appearance is recorded in Giuseppe Vasi's Magnificenze di Roma as well as in photographs. Also confirmed is Sardi's authorship of the façade of the Trastavere church of Santi Quaranta Martiri . This façade appears to have been modelled on that by Francesco Fontana for the church of Santa Maria ad Nives, Rome, located near the Colosseum, and erected around 1708. More contentious are Sardi's contributions to two other churches that had new façades finished in the period between 1720 and 1740. The first of these projects was the construction of a new façade for San Paolo alla Regola, a church which had been erected around 1687 to a design of Father Giovanni Battista Bergonzoni, a teacher of theology at the college attached to the church. Vasi claims that the façade was the design of Giovanni Battista Conti, while Titi attributes it to 'Ciacomo Ciolli’ and Sardi jointly. In sum, there is no scholarly consensus on how exactly the work should be divided. A similar problem concerns the attribution to Sardi of the facade of Santa Maria Maddalena which is significant as one of a limited number of facades in Rome displaying the Rococo style, The facade was begun in the late seventeenth century and was still unfinished in 1734. Rossini's Mercurio errante and the 1745 edition of Roisecco's guide book do not mention the designer, although they do draw attention to the façade. The first mention of Sardi's involvement is in the 1750 edition of Roisecco's guide book. Scholars have long been undecided who should be credited with this design which has also been attributed to Emanuele Rodriguez Dos Santos. Too little of Sardi's work survives to permit attribution on stylistic grounds.
