After studying at the École Nationale Supérieure des Beaux-Arts and under the architects Peyre, Blouet and Duban, Charles Questel began his career as an architect for public institutions in the 1820s and gradually rose through the ranks of the Commission for Historic Monuments and the Council of Civilian Buildings. He made a name for himself in particular with the construction of the Saint-Paul church in Nîmes between 1839 and 1849, as well as the Prefecture of Grenoble from 1861 to 1866, the library-museum in the same city from 1872 to 1876 and the Sainte-Anne hospital in Paris, which opened in 1867.
In 1849 he became head architect at the Palace of Compiègne and the Palace of Versailles, where he worked for 30 years. His work at Versailles notably included the renovation of the arena in the Great Stables and the restoration of the upper sections in the Marble Courtyard and part of the Royal Chapel.
Charles Questel was also the creator of two new structures: the museum of Coaches in Trianon (built in 1851 then demolished in 1978 for the construction of the Cold Pavillon ) and the staircase in the North Wing, which is named after him and adjoins the Royal Opera House. This staircase replaced the one built by his predecessor, Frédéric Nepveu, during the July Monarchy.