Trouard was born in Paris to a wealthy father who was a sculptor and supplier of marble to the king.[1]
Trouard studied with Louis-Adam Loriot at the Académie de peinture. Winner of the academy's grand prize (the predecessor to the Prix de Rome) in 1753, he studied at the Académie de France à Rome from 1753 until 1757.[1] During his stay in Italy from 1754 until 1758, he created a travelogue that described innovative trends in architecture, as well as the medieval architecture of Pisa.
Upon his return to Paris, he constructed a house for his father at 9 rue du Faubourg-Montmartre. The construction employed a Greek frieze evoking the style of one of his classmates in Rome, Pierre-Louis Moreau-Desproux. He built another house for his father in 1761 at 1 rue du Faubourg-Poissonnière (the house has since been destroyed).
Under the protection of Monseigneur de Jarente, he was made the architect of the royal commissaries who were responsible for the construction of religious buildings with funds seized from fleeing Protestants. In 1764 he added the Chapel de la Providence (now the Chapelle des Catéchismes) to the church of Saint-Louis at Versailles (now Versailles Cathedral).
He then commenced construction of the church of Saint-Symphorien, the third parish of Versailles, which he built as a basilica.[1]
In 1773, Trouard was forced to leave Versailles and return to Paris for his reputed involvement in an embezzlement scandal.[1] King Louis XVI later cleared him of the accusations.
