Ledru moved to the Auvergne in 1810, where he started a business in asphalt extraction.[3] By 1811, he designed the spa in Le Mont-Dore.[3] By 1820, he designed the Hôtel de Ville complex, which included the town hall, courthouse and prison, as well as the slaughterhouse, the market, etc., in Clermont-Ferrand, where he was appointed as chief architect in 1823.[3] He also designed the courthouse in Thiers and a government building in Ambert.[3]