Gabriel projects concerning City Hall of Rennes, in 1732, going towards the construction of a large ensemble, including a separate building south of the site for the governor of the province of Britain. The price of this construction, at the charge of the city, is considered prohibitive by the city council chaired by François Toussaint Rally du Baty and abandoned. However, to accommodate the worthy commander in chief of the province, the municipality is considering leasing the hotel Blossac for the sum of 6000 french livres per year (4000 livres from 1740 to 1754), a solution accepted by the widow Louis Gabriel La Bourdonnaye, who died in 1729. From 1732 to 1789, the hotel was Blossac the residence of the commander.
