ACECO was hired by the Clark-Christman Joint Venture to provide demolition, shoring, abatement, and excavation services in the efforts to renovate the Cannon House Office Building (CHOB) which is controlled by The Architect of the Capitol. Located on Capitol Hill, The CHOB is the oldest Congressional office building besides the Capitol Building. This is a 4-phase renewal project in which ACECO has had and will have the pleasure of working on all phases as well as the preparatory phase 0.
The current Phase 3 focuses on the East wing along First Street. The East Wing requires selective interior demolition of the ground floor through 4th floor, structural demolition of the 5th floor and roof, and asbestos abatement. Historical preservation and design changes are the biggest challenges on this project. With the careful efforts of both our day and night shift crews and ACECO’s historic appreciation, we have been able to navigate the demolition activities safely while preserving the history of the building. Built in 1908, the building has seen many minor renovations and changes to design. With the assistance of the Clark-Christman Joint Venture, ACECO has tackled any design changes while maintaining the schedule and production.
ACECO was contracted to perform the design and installation of the structural support, demolition of the foundation wall, interior demolition, and excavation, all while protecting the historic facade above. To support the existing building wall and facade, a detailed steel support system was installed utilizing the existing interior building columns as the main load bearing elements. Beams, tube steel, needle beams, diagonal braces, and knife plates were installed to support the building wall and exterior facade. This complex support allowed the foundation wall to be demolished under strict vibration and movement thresholds, creating the illusion of a “floating” building until the new addition is constructed, while meeting the aggressive project schedule.