In 1489, a columned vestibule and octagonal sacristy, designed by Simone del Pollaiolo, known as Il Cronaca, and Giuliano da Sangallo respectively, were built to the left of the building.
ɪn wˈʌn θˈaʊzənd fˈoːɹhˈʌndɹɪd ˈeɪɾi nˈaɪn, ɐ kˈɑːlʌmd vˈɛstɪbjˌuːl ænd ˈɑːktɐɡənəl sˈækɹɪsti, dɪzˈaɪnd baɪ sˈɪmoʊn dˈɛl pəlˈeɪəlˌoʊ, nˈoʊn æz ˈɪl kɹənˈɑːkə, ænd dʒɪjˈuːliˈɑːnoʊ dˈɑː sæŋɡˈæloʊ ɹᵻspˈɛktɪvli, wɜː bˈɪlt tə ðə lˈɛft ʌvðə bˈɪldɪŋ.