How Life Cycle Assessment Results Can Inform a Triple Bottom Line Cost Benefit Analysis in the Built Environment

ABSTRACT

Life cycle assessments (LCAs) are an analysis technique to help design professionals assess the comparative environmental impacts associated with different building components and design options. The impacts studied typically include Acidification Potential, Eutrophication Potential, Global Warming Potential, Ozone Depletion Potential, Smog Formation Potential, and Primary Energy Demand with a full cradle-to-grave or cradle-to-cradle scope. The application of LCA software within a detailed architectural model first requires the accurate assignment of material specifications to all building components. This then outputs specific material quantities and allows the LCA software to extrapolate those quantities to the large body of research about the environmental impacts.

Material quantities are also a critical component in assessing the environmental impacts of embodied carbon in our buildings. The project team took the outputs from the completed LCA, and placed them into a Triple Bottom Line-Cost Benefit Analysis. Autocase design valuation software allowed the project team to financially quantify the environmental, social and economic costs and savings of different design options for this adaptive reuse project. However, the marriage of these two analyses specifically allowed for the calculation of the social cost of carbon by leveraging the body of empirical economic research on the subject. Core and shell reuse constituted of 12% wood, 99% concrete, 60% steel, 3% glass, 100% brick, and 2% of drywall. The results concluded that an estimated $2,297,000 of negative social externalities due to carbon emissions alone were effectively avoided on the project; one of many positive outcomes of building reuse that these software enumerate.

Life Cycle