Exterior stone repair begins Minnesota State Capitol Restoration Project
Façade work staged in three phases through 2015; scaffolding to cover northeast section
February 20, 2013
ST. PAUL – The Minnesota Department of Administration announced that the project to repair and preserve the deteriorating Georgia Marble façade begins this week. This key phase of the Minnesota State Capitol Preservation Project work focuses on stone repair and replacement to ensure public safety, prevent water infiltration, and preserve the historical character.
The exterior stone repair will occur in three phases with each phase lasting approximately a year. Crews are installing the roof mounted swing scaffolding this week. Additional scaffolding will be erected from the ground up to the roof around the building’s northeast portion beginning in March (see attached document for the phasing schedule).
With the scaffolding in place,stone repair specialists will begin the exacting process of measuring and fabricating replacement stone. The replacement pieces will be made from twelve large blocks(approximately 1,400 cubic feet) of Georgia White Marble purchased from a quarry located near the site from which the Capitol’s architect, Cass Gilbert,selected the original marble for the Capitol Building.
“The critical exterior repair is the most visible effort to date in our efforts to preserve this Minnesota treasure,” said Administration Commissioner Spencer Cronk. “Just two years ago we built emergency scaffolding to protect citizens from falling marble. Today’s scaffolding is helping us preserve that same marble for the next century.”
Experts have been conducting assessments and testing repair methods at select areas around the Capitol’s façade since mid‐October. The investigations found long‐term water infiltration that has saturated masonry behind the marble, stone and brick damage from the freeze/thaw weathering cycles, corrosion of the material used to anchor the stones to the building, and shifting of stonework. Testing has focused on the techniques to repair these issues and the visual impacts of such repairs.
The team doing the work is comprised of nationally recognized historical exterior stone repair experts and local firms with extensive experience working on the Minnesota State Capitol. The design firm HGA and the engineering firm Wiss, Janney, Elstner spearhead the design team. Contracting firms are JEDunn (Construction Manager), Mark 1 (Installation), Advanced Masonry Restoration (Repairs), Polycor (Marble Supplier), Traditional Cut Stone (Decorative Carving), and Twin City Tile and Marble (Field Measuring).
In 2012,the Capitol Preservation Commission unanimously approved a comprehensive restoration plan estimated at $241 million. The project is designed to be completed in phases and includes repairs to the deteriorating façade, modernization of the mechanical, electrical, plumbing, life‐safety,security and telecommunication systems. This work will be accomplished while preserving the architectural integrity of the Historic Capitol Building in keeping with Cass Gilbert’s original design. Initial work is funded through a $44 million appropriation passed in the 2012 bonding bill to begin restoration work and build a security tunnel underneath University Avenue.
For more information on the façade repair and the entire preservation project, please visit the Commission’s website.