Architect: BCV Architects
Structural Engineer: Rutherford & Chekene
Sustainability Consulting: ROMA Design Group (Landscaping), Arup (LEED and MEP)
Project location: San Francisco, CA
Most structures only last 35-60 years, particularly in a region concerned with seismic safety. With structural elements dating back to 1967, The Cannery had reached its time horizon for expected replacement of the structure. Rather than simply replacing the building, however, the design team considered how much in environmental resources was already invested in the original structure and its multiple retrofits. The client sought to preserve not only the aspects of the original structure, but also the evidence that told its story as the region’s first example of adaptive reuse. Reuse of existing structure is one of the most significant ways to reduce the embodied environmental impacts of construction.
The Athena EcoCalculator was used to model the environmental implications of preserving the building’s primary elements: masonry walls, steel framed floors with concrete slab, and foundation. Embodied energy, embodied carbon, and waste metrics were chosen to best represent the environmental concerns at hand.
Existing drawings documenting original construction and multiple retrofits were consulted, and the total area of each assembly type was input in the EcoCalculator. The Cannery was of typical historic brick wall and steel frame construction, later retrofitted with shotcrete and rigid diaphragm floors; as a result, the area of masonry walls, steel joist floors, steel columns and concrete walls were the primary inputs. The pad foundation and shotcrete were not found under the standard assemblies offered by the EcoCalculator. After consulting with Athena experts, the team added an additional area of concrete floor equivalent to the volume of the concrete foundation, using 6” cast-in-place to represent shotcrete.
The EcoCalculator results indicated that preserving The Cannery’s structure was equivalent to:
- saving enough energy to power 500 homes for one year;
- saving the amount of carbon it would take nearly 380,000 trees over 10 years to sequester; and
- avoiding an amount of waste that would fill 2.2 football fields
These quantities were calculated by converting EcoCalculator output using the EPA Greenhouse Gas Equivalencies Calculator for the first two statements, and for the third, using data from Arup’s waste group regarding typical construction waste density and assumed landfilling to 3 feet high.
Quote from Sustainability Team:
“The EcoCalculator was chosen because of how well the building construction materials matched the assembly choices. The simplicity of the spreadsheet-based tool also aligned with the limited time and budget, and the understanding that the client only desired a rough estimate, in a few widely understood metrics.” – Frances Yang, Sustainability Team
Photo courtesy of Arup.