Reconciling Apples with Oranges: Comparing the Performance of New and Retrofitted Green Buildings from Design to Post-Occupancy Evaluation

Ihab Elzeyadi University of Oregon

Employers, building owners, designers, and developers are persuaded, in response to an increasing marketing campaign by the building industry, that green buildings affects the health and well-being of occupants. As a result, many business owners attempt to build or renovate their building stock and certify it to green buildings standards. With staff accounting for 90% of business operating costs, a 1% improvement in productivity and well-being can have a major impact on the bottom line and competitiveness of any business. Despite the favorability of these projections, these findings have not been equally confirmed related to the impact of green buildings new construction or major retrofits on their occupants. The specific question of this project is whether there is conclusive difference between green newly-constructed buildings and those retrofitted to green buildings standards on their building performance and the occupants’ perceptions.

This presentation reports on a longitudinal assessment of two educational high performance LEED™ platinum buildings from design to Post-Occupancy Evaluation (POE), comparing building performance as well as occupants’ perceptions of multi-comfort, satisfaction, well-being, health, and productivity. The buildings were monitored for Indoor Environmental Quality (IEQ) parameters of visual, thermal, acoustical, indoor air, and spatial comfort over a period of one year after 12-months of continuous occupancy. IEQ measurements were performed and standardized POE surveys were conducted. Results show strong correlations between thermal, acoustical, and indoor air qualities of the newly constructed green environment that is well correlated with improved employees’ productivity and satisfaction. Visual comfort and perceptions of the impact of the building on employees’ satisfaction and productivity varied between both building types. Lessons learned and recommendations for future applications of the design innovations employed for both new construction green-certified buildings and majorly renovated ones are discussed.