Portland State will build green roof research site on Walmart’s new North Portland store
Author: Christina Williams
Posted: October 23, 2013

The design of green roofs is poised to improve as a result of a two-year research partnership between Portland State University and Walmart. Data collected from the roof of Walmart's new Hayden Meadows store—the largest green roof installation in Portland—will provide insights for the design of energy efficient, habitat friendy, stormwater filtering, and heat mitigating green roofs.

PSU’s Green Building Research Laboratory will lead the effort to put scores of sensors and a weather station on the north Portland store roof, which will feature 40,000 square feet of vegetative roof installed in three separate sections—each devoted to testing different aspects of green roof design, such as materials and soil depth. The remaining 52,000 square feet of white membrane rooftop will also be monitored by sensors, providing an opportunity to deliver side-by-side comparisons on factors including surface temperature, water flow and building operations. Data collected from the Hayden Meadows roof will be compared to similar data collected on a Walmart green roof in Chicago, providing a comprehensive view of green roof performance in various conditions. 

“The data we collect will help the green building industry improve upon the many benefits provided by green roofs—from reducing heat island effects to improving overall building performance,” said David Sailor, director of the PSU Green Building Research Laboratory and professor of mechanical engineering. “This research project will lead to better green roof design for buildings around the world.” 

The PSU Green Building Research Laboratory, housed at the Maseeh College of Engineering and Computer Science and funded in part by the Institute for Sustainable Solutions, will lead the two-year research project working with students and community partners. The city of Portland’s Bureau of Environmental Services will measure stormwater runoff; the Cadmus Group, an environmental consulting firm, will monitor the performance of the rooftop air conditioning units; and the Audubon Society of Portland will conduct bird count surveys to contribute to the habitat monitoring portion of the study. 

Because the rooftop features both a green roof installation and a more traditional white membrane roofing material, it provides an ideal test bed for measuring and comparing building performance data.  

The Walmart Haden Meadows research project builds on PSU’s growing expertise in green roof design and monitoring that has been funded by organizations including the National Science Foundation, the U.S. Green Building Council,  the U.S. Environmental Protection Agency and the Oregon Built Environment and Sustainable Technologies Center.

More from Walmart

In December, the Walmart Foundation provided a $98,608 grant to expand a PSU-led effort to get healthy food to kids. Read about it.