[2] Preliminary design drawings by Wright show that the front or northeast side of the chapel was to be decorated with a modest fountain and pool, which, together with a bas relief plaque identify the structure as a memorial to Dr.The porch not only incorporates the open terrace common to other Wright designed buildings of the era but also has an explicit functionality.[5] It embodies the very essence of Frank Lloyd Wright's Prairie style buildings: the roof and its overhanging eaves, the abstract geometric art glass windows, the raised functional floor and the "plastic expression" of the stucco exterior and its contrasting wood trim.[3] The Pettit Memorial Chapel was added to the U.S. National Register of Historic Places on December 1, 1978,[3] Although the National Register nomination discusses Wright's work in relation to several significant monuments designed by Louis H. Sullivan, it is important to note that the Pettit Chapel is not a tomb or mausoleum but a functional building.It is more productive to view the Pettit Chapel and its architectural significance in the context of Wright's Prairie-style residential work of the period.The residential character of the chapel is consistent with its intended use as a place for funeral services and gatherings as well as a shelter for visitors to the cemetery.