The former Gimbel's department store is a fourteen-story steel-frame structure in the heart of Pittsburgh's most densely populated business district, featuring a wealth of classical detailing. It is a major visual anchor to the district and a critical element in its retail sector. As has been typical in recent urban cycles, the department store was closed and the building vacated in 1984. In 1998, as part of the effort to restore the urban core, the architectural firm of Burt Hill Kosar Rittelmann Associates developed renovation plans for the aging structure.

The most ambitious element of the design was cutting a fifty-foot-diameter octagonal atrium in the middle of the structure, from the fourteenth to the seventh floor. The resulting light on the one-acre interior floor plate attracted the Heinz Company to locate their North American operations headquarters in the top seven floors. The architects also suggested complementing the atrium with a green roof on the thirty-foot-wide terrace surrounding the fourteenth floor executive offices. The green roof provides enjoyable views of a variety of flowering plants from the offices, the integrated decks and paved patio areas, and it is used for out-door meetings and gatherings, allowing employees to experience the landscape beyond the glass-curtain walls. The ground cover also provides an acoustical damper in the brick and glass-enclosed terraces.

Roofscapes Inc. developed plans for both detailing and implementation of the 12,000-square-foot roof. Roofscapes elected to use a two-layer Roofmeadow® Type III: Savannah assembly, with three inches of engineered growth media over two inches of engineered drainage media, in order to enhance the droughtresistance of the green roof ecosystem. The Carlisle Syntech 045 EPDM waterproofing is supplemented by a polyethylene root barrier. The growing media was tested according to standard European methods published by Forschungsgesellschaft Landschaftsentwicklung Landschaftsbau e.V. [FLL] (1995) and has a Maximum Water Capacity (FLL) - 1.65 inches (fully drained condition) and annual rainfall retention - 55 percent (predicted).

The Burt Hill landscape firm designed an undulating rhythm of planting around the roof perimeter. Roofscapes, Inc. selected appropriate plant varieties to achieve accents in plant height, texture and bloom color. To capitalize on the changeable micro-climatic conditions created by the high walls, a wide range of plants that can tolerate the xeric conditions on the roof were specified. The diversity of plant textures, heights and colors in the maturing cover is visually exciting. Selected by Roofscapes, Inc. to satisfy the pattern of texture and color desired by the designers, the plants range from low-growing groundcovers like Sedum spurium and Phlox pilosa to tall varieties like Carex annectens, Anthemis tinctoria, Dianthus deltoides, Festuca ovina and Chrysanthemum leucanthemum. The planted areas will tolerate light pedestrian traffic and no irrigation is required. For meetings and recreational use, high-density recycled plastic lumber roof decks were constructed in four locations. They are integrated with paved patios, constructed to encourage the free flow of water between the paved and vegetated areas.

The thriving project is visible from most of the major downtown office towers. It demonstrates how green roofs can reduce the heat island effect and improve the habitability of urban office space in downtown Pittsburgh. Citing this "flagship" example, the Mayor has been encouraged to introduce incentives for more urban green roof projects in Pittsburgh.