Oct 1 2009
SGH and EADP Teamed to Restore Landmark Milwaukee City Hall
Building Design and Construction magazine this week announced that Simpson Gumpertz & Heger Inc. (SGH) and Engberg Anderson Design Partnership (EADP) won a Platinum Reconstruction Award for their restoration of Milwaukee City Hall. The award is granted to exceptional renovation, preservation, and adaptive re-use projects across the country.
Milwaukee City Hall, a registered historic landmark, was designed by H.G. Kogh & Company and built in 1896. The nine-story Flemish revival-style building is clad with sandstone, brick, and architectural terra-cotta and is topped by a slate mansard roof with step-gabled dormers. At the south end of the building, a 390 foot masonry- and steel-framed clock tower is topped by a copper-clad spire supported by steel trusses. After more than 100 years of harsh weather and stop-gap repair measures, the City of Milwaukee decided it was necessary to fully repair the historic building in 2001. SGH has been involved with this project since the beginning by performing the initial investigation to discover the sources of cracking, leakage, and general deterioration.
Following a national competition, the City of Milwaukee hired EADP and SGH to design and coordinate the complex repairs required for this building. Teamwork was a necessity for all involved in this project, because the owner and the community were deeply invested in the restoration of this historic landmark building. SGH, EADP, the general contractor J.P. Cullen and Sons, Inc., and highly specialized craftsmen worked together to repair and return the building to its original grandeur, while overcoming some of its original design flaws.
“This award recognizes not only the technical expertise of the entire design team, but the creative thinking required to solve the problems that had plagued Milwaukee City Hall for years,” said Glenn Bell, SGH Chief Executive Officer. “By combining traditional materials with modern methods and techniques, SGH and EADP worked to extend the life of this historic landmark for generations to come.”
The solutions to the building’s structural and waterproofing problems required highly technical engineering analysis, including remote monitoring of the building’s movement patterns with sensitive thermocouples and vibrating wire strain gages. SGH downloaded and analyzed the data from the instruments for one year. The monitoring and advanced analysis revealed systemic structural problems with the tower’s upper floors, which required significant strengthening and redistribution of loads using reinforced concrete ring beams, in-plane stainless steel anchors, and pre-cast elements. In addition, embedded steel and roof framing in the South Tower were severely corroded due to leakage and long-term water accumulation in the masonry. These conditions required replacement and strengthening of these elements. As part of this work, contemporary waterproofing materials and cavity wall construction techniques were employed to protect framing elements and drain moisture accumulation.