Klepper, Hahn & Hyatt Wins International Award for Courthouse Project

Klepper, Hahn & Hyatt has won an international award for its design work on the Building Envelope Restoration of the Onondaga County Courthouse.

The Copper Development Association, in collaboration with the Canadian Copper and Brass Development Association, has honored the project with a 2009 North American Copper in Architecture Award in the Restoration/Renovation category. Only four projects were selected for this category, two in the United States and two in Canada. Eight projects in the New Construction category were selected, again in both the U.S. and Canada.

An award presentation took place at the offices of Klepper, Hahn & Hyatt in November. Two representatives from the Copper Development Association, county officials, and members of the design and construction team were present.

The award recognizes the design and craftsmanship involved in restoring the copper elements of the Courthouse, including the central dome and the four satellite domes. These domes were all original to the building. The ornamentation was faithfully replicated; however, the waterproofing details were greatly improved for longevity and low maintenance.

As the lead professional design firm, Klepper, Hahn & Hyatt researched the existing construction on the 100-year-old Courthouse, studying what was in place and why failures had occurred. KHH then established the performance requirements for the project, specifying the level of quality and detailing, and working closely with the general contractor, Hueber-Breuer Construction Company, and the roofing contractor, Henderson Johnson Company, both of Syracuse.

The Courthouse was listed on the National Register of Historic Places in 1980 as part of the Montgomery Street-Columbus Circle Historic District. The building envelope restoration project marked the Courthouse's Centennial.

Two ACI Awards Highlight Firm’s Diversity

Klepper, Hahn & Hyatt earned two awards from the American Concrete Institute - Central New York Chapter which showcase the firm’s professional diversity.

The Gold Award for Excellence in Masonry Design and Installation was given to the Spear House Masonry Facade Restoration for Colgate University in Hamilton, New York. An Award of Merit for Excellence in Concrete Design and Installation went to the East Hills Senior Living Center in Binghamton, New York. Spear House involved exterior restoration for an 1835 stone masonry building, while East Hills was new construction involving sustainable criteria for concrete installation. These are both project types for which KHH has considerable expertise.

Spear House was built by the Baptist Education Society in 1835, and purchased by faculty member Philetus Bennett Spear in 1838. “Claremont,” as it was then known, was a faculty residence and fraternity house for a full century, before being gutted and renovated in 1935. It housed the Samuel Colgate Baptist Historical Collection until 1947, when it was again renovated for university offices. It currently houses the Center for Career Services.

Spear House is a solid stone masonry, bearing wall building with a wood framed roof structure. The wood floors were replaced with steel and concrete in 1935. The exterior walls consist of rubble stone masonry with traditional lime putty mortar. This facade restoration project focused on investigating the causes of problems which had become evident in the facade, and finding the best way to correct those issues to preserve the building and ensure its longevity.

The building’s relative antiquity mandated a sympathetic use of materials which replicated the original, applied with current methods and craftsmanship. Project work included:

• Removing and rebuilding the high stone parapets on the east and west sides
• Repairing wall cracks and open joints on all elevations, plus cracked stone sills, lintels, and water tables
• Rebuilding of bulging wall sections where voids were created when chimneys were removed in the 1930s
• Repair of rotted timber roof beams.

KHH chose natural hydraulic lime as the repointing mortar. It has greater strength and durability than lime putty mortar, while also providing a high moisture transmission rate, similar to the original lime mortar.

Viau Construction, the masonry contractor, further enhanced the project through skillful practices and applications.

East Hills Living Center in the City of Binghamton was one of several projects which boosted the number of affordable senior developments in Broome County. The development consists of 32 townhouse-style, one- and two-bedroom units within seven residential buildings, plus an eighth building which serves as a Community Center.

The single-story buildings have wood-framed roofs and superstructure walls. Foundation walls and footings are conventional cast-in-place concrete, as are the slab on grade floors. Design and materials for the concrete installation employed sustainable green building criteria. The project architect was Bearsch Compeau Knudson.

While the concrete foundation design is quite conventional, the edge of the slab incorporates a fairly unusual detail. The top of the rigid insulation, which is vertically up against the inside face of the foundation walls, has a 45-degree bevel with the top extending up to the slab finish elevation. This is a detail that is in compliance with the New York State Energy Conservation Construction Code; however, it is not done very often due to various concerns about potential problems. This project showed that this detail can be successfully implemented.

A surprisingly high level of building heat escapes out of an uninsulated slab edge, even though this area represents a relatively small percentage of the building envelope’s total surface area. The thermal mass of concrete is very high; a large amount of heat is stored in the interior slabs. When the slab edge is not insulated, it is thermally connected with the exterior, and the heat is continually drawn out of the building. This is evident in images taken with thermal cameras, and can be quantified with good building energy modeling programs. When a building’s walls and roofs are tight and well insulated, a higher percentage of heat loss occurs at uninsulated slab edges. Thus it is even more important to have good foundation insulation details.

The large thermal mass of interior concrete - both slabs on grade and building structures - can be very advantageous in maintaining uniform temperature levels if the concrete is kept inside a properly-insulated building envelope, especially adjacent to the concrete elements. Studies have shown that concrete buildings are, in fact, more energy efficient than buildings built with materials of lower thermal mass, when both buildings are equally insulated.

Although the detail with the beveled top insulation edge seems awkward, it is the most practical way to provide effective insulation at the slab edge for a foundation wall that is insulated on the inside face. If this detail were not used, the buildings would have a large amount of heat loss through the tops of the foundation walls during heating seasons for the entire service life of the buildings.

All of the concrete that was used in this construction had 20 percent of its Portland cement content reduced by the use of fly ash. This included the footings, foundation walls, and interior and exterior slabs on grade. The incorporation of fly ash reduces the production of Portland cement, which in turn reduces the amount of carbon dioxide emitted into the atmosphere.