Washington, D.C.

The United States Capitol Dome is composed of cast iron plates secured to cast iron structural members. The iron serves as both structure and envelope protecting the interior from the elements. Throughout the dome there was moisture intrusion problems related to the joints (butt and overlapping) of the cast iron plates. Our scope of work included removal and replacement of approximately 17,000 lineal feet of sealant joints and installation of a waterproofing membrane behind the Antifixae in conjunction with the interim painting work in the summer of 2010.