He moved to Venice by 1716, where he began collaborations that spanned over four decades with Giovanni Battista Tiepolo and his son Giandomenico.
[1] It is presumed that the two latter artists collaborated in decorating the octagonal room of the Villa Morosini Vendramin Calergi in Fiesso Umbertiano.
Mengozzi's first collaboration with Tiepolo was the decoration of the hall on the first floor (1719-1720) of the Villa Baglioni in Massanzago, depicting the Myth of Phaeton on the walls and the Triumph of Aurora on the ceiling.
[4] The ceiling depicts Bellerophon on Pegasus in flight toward the Glory and Eternity, while the walls are frescoed with the Meeting and Banquet of Anthony and Cleopatra.
In 1754 he completed architectural perspective for scenes filled with figures by Giandomenico in the church of Santi Faustino e Giovita in Brescia.
[6] In the Palazzo Rezzonico, Tiepolo and Mengozzi were commissioned to decorate rooms for the wedding of Louis and Faustina Savorgnan.
In the wedding room ceiling, we see the couple carried on Apollo's chariot, drawn by four white horses, preceded by Cupid, blindfolded and surrounded by allegorical figures: the three Graces, Fame, Wisdom, bearing the flag of Merit with the heraldic arms of the Rezzonico and Savorgnan family.