North Extension Pediment Sculpture

We performed conservation repairs to the East facing pediment sculpture group, Progress of Civilization, as part of the exterior stone restoration campaign of the U.S. Capitol Building, North (Senate) Extension.

Like the South Extension pediment, the Capitol’s North Extension pediment is enriched by the major program of sculpture that speaks to the history, development, and values that underlie this country. The sculpture group was carved in Lee, Massachusetts marble by Thomas Crawford in 1854 and installed in 1863. It depicts a variety of figures germane to the onward march of democracy.

Before our team executed work on these sculptures, our conservators performed a condition assessment in 2016. This assessment aided to develop a scope of work that included cleaning, stain removal, removal and replacement of bird deterrent system, removal and replacement of joint mortars and sealants, and conservation repairs. The conservation repairs, included laser cleaning, consolidation, crack injection grouting, application of a shelter coat, stabilization of fragile elements, and rebuilding and replacement of lost features. Our scope of work was completed in 2018.