The $15.8-million skirt restoration of the U.S. Capitol dome, which is composed of nearly 4,500 tons of iron, resolved deterioration and life-safety concerns involving cast-iron decorative and structural elements located at the dome's exterior. Work included interior and exterior lead-paint abatement and repainting of all cast-iron plates and trusses; repair of severely deteriorated cast iron; repair and cleaning of sandstone and historic brickwork; the application of protective epoxy coatings; and drainage redesign and improvements.
Paint removal revealed numerous unforeseen challenges. After the removal of lead paint from the original sandstone, lead was still detectable three to four inches into the stone. Full remediation was not an option. Instead of using Dutchman repairs, the project team chose to repair the cracked units to limit the lead-abatement procedures required for stone removal.