Completed in 2018, the project introduced floor-to-ceiling structural glass at the observation deck, open-air glass benches, a rotating glass floor known as The Loupe, and a new glass-floored stair connecting the upper observation levels. The renovation enhanced the visitor experience while improving the building enclosure and energy performance of the 605-ft structure.
RDH served as the building enclosure consultant throughout design and construction. Working with Olson Kundig, our team reviewed enclosure details for air, water, thermal, and vapor performance, provided field review during construction, and assisted the project team in addressing enclosure-related performance issues. Near project completion, RDH conducted whole-building air leakage testing to evaluate the renovated enclosure against applicable energy code requirements.
Renovating an occupied landmark presented unique technical and logistical challenges. Construction was carefully phased to maintain public access, while whole-building air leakage testing required overnight coordination to account for oversized openings and the wind conditions at the top of the structure. The completed project introduced dedicated air and thermal barriers to a building that previously lacked insulation and achieved LEED Gold certification in 2020.
