Architect of the Capitol

Olmsted Terrace

Project at a Glance

Washington, DC


Architect of the Capitol

Project Type


Project Overview

  • Exterior masonry rehabilitation of 120-year terrace walls designed by Frederick Law Olmsted
  • Managed logistics and safety adjacent to the highly active Capitol Building
  • Technical challenges included removing dirt and staining with microabrasion while not damaging the highly deteriorated stone

Frederick Law Olmsted was hired to design the U.S. Capitol Grounds in 1874. His goal was to create a landscape and hardscape that complimented the Capitol buildings and enhanced the daily routines of legislators, staff and visitors. For 120 years, very little restoration occurred at Olmsted Terrace. This multi-phased project with the Architect of the Capitol (AOC) included the restoration of the marble and granite hardscape to its original condition. Scope also included the removal and reinstallation of capstones to allow for waterproofing below. Repointing, dutchmen repairs and the cleaning and consolidation of stained, damaged stones was also performed.

The cleaning portion of the project was done through the use of detergents, microabrasion and poultice application to the marble center upper west terrace at the U.S. Capitol Building. In addition to cleaning, all joints were cut out and repointed and the existing joint sealants were removed and replaced. Dutchmen repairs were made using Danby or Lee marble depending on the location.