THE Hunter Museum of American Art
Designed by architect Randall Stout Architects, the Hunter Museum of American Art is Zahner's first project with the renowned firm. Mr. Stout grew up in Tennessee, so to be chosen to design Chattanooga's new wing of the Hunter Museum was particularly meaningful for both the community as well as the architect.
The Museum sits on an 80' tall bluff above the Tennessee River where the building's dynamic lines and twisting curves provide a contrast to the original museum's classic style, adjacent to Randall Stout's contemporary design. In 2002 the Hunter Museum of American Art partnered with the City of Chattanooga, the Tennessee Aquarium and the Creative Discovery Museum to finish the 21st Century Waterfront Plan.
Zahner produced the geometric zinc metal surface as well as the curvilinear Angel Hair stainless steel roof forms, interior stainless steel stairway, and various metal details throughout the building.
The City of Roanoke, Virginia is situated in a famously mountainous landscape. Situated at the the southern end of Shenandoah Valley, with Blue Ridge Mountains and the Appalachians, its location is not where one would think to find a contemporary museum. However, this was the objective, to develop a museum as part of a comprehensive plan to invigorate the city. Designed by Randall Stout Architects, the building includes a range of metal components manufactured and installed by Zahner engineers and artisans. Zahner was responsible for engineering, fabrication, and installation of the exterior secondary structure and facade. Zahner also provided interior metal surfaces for the project. The building's earth-toned exterior is a custom-patina product that Zahner refined for the Museum. Roano Zinc is a zinc plate surface with a custom patina. The preweathered surface provides a stable, matte surface, which stands the test of time against weathering. This preweathered zinc metalwork is used on both the exterior and interior surfaces. The surface of the lightly reflective metal is stainless steel with Angel Hair, a Zahner-patented mechanical finish on stainless steel.The project's secondary structure used to create the complex angles and curves used ZEPPS, a patented system developed by Zahner for constructing unique shapes. The system was used to design and build the complex forms used in the project. ZEPPS simplified the construction process, ensuring a smooth delivery for the building's unique forms.
Selecting the Surface
The architect's specifications originally called for a limestone exterior in additional to the stainless steel curving roof. Limestone would have cladded the vertical walls as well as many of the slanting angles throughout the building. As the project progressed, it became apparent that installing limestone was implausible in many areas due to the structural weight of the material.
At this point, Zahner was already contracted to produce the stainless steel roof. The architect asked Zahner to come up with some textured surfaces to match the limestone aesthetic.
Zahner had already been developing a wide range of custom patinas on many alloys of metal. The design team worked through several options, and decided to replace the limestone with a light gauge Hunter Zinc panels system. The preweathered zinc surface has a tonality which closely resembles the limestone surroundings. This material was used throughout the museum, on both the interior walls and the exterior building envelope.
Building the Hunter's Curves
The bright curving stainless steel surfaces on the Hunter Museum use two signature Zahner systems, ZEPPS and the Inverted Seam system. These systems combine to make a roof which curves exactly as the architect's original drawings. This curving surface is visibly seamless and completely protects the building against the elements.
The stainless steel is treated and processed with the Angel Hair mechanical finish, which reduces the glaring hotspots common on more reflective stainless steel, and enhances the sheen and glowing bounce of light that it generates.
The most efficient and effective way to build these curves is with large ZEPPS assemblies which are produced in the fabrication shop and shipped to the site as preassembled massive panels, as pictured above the construction workers in the reference image, above.
Each of these ZEPPS lines up with adjacent panels, and includes flexible connections which allow for tolerance if the structural steel that it bolts onto is misaligned. Ensuring the subtle curvatures is crucial, so building in these types of safeguards is an effective way to save time and money during the installation process.