The Second Empire style, also often known as the Mansard style, takes its name from the reign of Napoleon III (1852-70), France’s Second Empire, during which many buildings were in built in France with the distinctive mansard roof. The boxy mansard roof allowed full use of the attic story and consequently, the style became very popular for new construction as well as the remodeling of existing buildings. The roof is often punctured by dormers and dormer windows of various shapes.
Frederick Ayer Mansion (1876), 357 Pawtucket Street
Levi Sprague House (1867), 52 Mansur Street
Daniel Holt House (ca. 1870), 4 Park Street
Wentworth Building (1845; mansard roof added ca. 1865), 256 Merrimack Street
The Second Empire style also borrows heavily from the Italianate style. Ornamental brackets under the roof cornice and under door and window hoods are often found on Second Empire residences. First appearing during the 1850s in the United States, the style dominated American house construction between 1860 and 1880.
The style was often used for many public buildings constructed in the 1870s while in some cases, older commercial buildings often had mansard roofs added to increase usable space.