Building Reuse –
Transformation for a Purpose
Reduce, reuse, recycle; three ubiquitous words related to consumer products. This hierarchy also applies to the built environment and one of the most effective ways to reduce embodied carbon is to reuse a building rather than construct a new one. This not only saves the emissions associated with extracting and installing new materials, but also significantly reduces the waste produced in demolition.
Unfortunately, building reuse, while environmentally beneficial, can present significant hurdles for the design, permitting, and construction processes. Due to development patterns, there may not be available space where the demand exists, often making location the first challenge. Even when a building is in the right place, many other challenges such as changes in code provisions, societal desires for space quality, or required performance characteristics (floor rating, HVAC system, space layout) exist. To make effective use of existing buildings we must find strategies that allow us to efficiently renovate existing buildings and save the emissions “sequestered” within our building stock. The following two examples illustrate some of the challenges—and solutions—that are required to achieve these goals.
The $88 million renovation of Mickey Leland Federal Building, funded by the American Recovery and Reinvestment Act (ARRA), would not have been possible without Walter P Moore’s application of Performance-Based Design for Wind. The 22-story high-rise office tower in downtown Houston, built in 1983, did not meet current wind code; particularly when considering the vertical extension of the building by means of a new 12-1/2 foot parapet to conceal new rooftop equipment. The LEED Platinum renovation involved completely reskinning the precast building with a new insulated and laminated (blast-resistant) glass, improving energy performance by replacing the building’s mechanical infrastructure, and upgrading the facility security measures to meet Interagency Security Committee (ISC) Security Design Criteria “Medium” Level of Protection. As the structural retrofits were implemented while the building remained over 90% occupied, Walter P Moore was challenged to design nimble solutions that could be adapted to the various existing conditions that were encountered on each floor.
The estimated $72 million renovation and expansion of the 270,000-square-foot Sears department store in Houston’s Midtown into the ION is another example of building reuse. In 2017, Rice University’s endowment company bought out the remaining years of Sears’ 99-year lease for the property which Rice Management Company owns.
The transformation from retail store to innovation hub pays homage to the original art deco style of the 1939 structure, particularly at the ground level storefront. To vertically expand the existing three-story structure by two additional floors, most of the existing spread footing foundations will be strengthened. The existing roof framing has insufficient load capacity to serve as an occupied floor, so new framing will span over it directly to column locations. An additional challenge to repurposing the building includes infilling the existing stairs, elevators, and escalators while framing new stairs and elevators based on the ideal circulation patterns. Introducing daylight into the “concrete box” department store to transform it into a center for technology innovation involves new multistory punched openings in the exterior concrete walls and a new center lightwell angled through the building. Retrofitting the existing structure to accomplish these goals was made more difficult by the fact that the renovated structure will generally not have ceilings, so the structural elements will remain exposed. The approach to each retrofitted area had to maintain the aesthetic of the existing exposed concrete flat slab structure with drop panels at each column.
While the reuse and repurposing of existing buildings is highly effective at reducing embodied carbon, it poses numerous structural challenges as discussed. However, it can effectively address challenges while still delivering elegant, redefined buildings.