The World’s Largest Net Zero Energy Building
The desert environment in Phoenix can be harsh—the mercury tops 90 degrees an average of about 180 days annually—and the 40-year-old cement-block building targeted for an ambitious sustainable makeover was in a sorry state (located in the city’s re-emerging Discovery Triangle neighborhood, it formerly housed an adult-themed boutique). But that didn’t prevent DPR Construction and Interior Design Giant SmithGroupJJR, the country’s eighth-largest architectural and engineering firm with a focus on sustainable design, from spending just 10 months to acquire, permit and build a regional headquarters that not only achieved LEED Platinum certification in 2012, but also more recent certification as the world’s largest Net Zero Energy Building according to the International Living Future Institute (ILFI).
“While many building owners may think it’s impossible to turn an aging building into something forward-thinking and sustainable, that’s precisely what we’ve achieved for our new home,” says Dave Elrod, manager of DPR’s Phoenix office.
The $3.7 million, 16,500-square-foot project, located at 44th Street and Van Buren and completed in 2011, is the third in a series of sustainable offices constructed for DPR employees over the past decade, following San Diego and Newport Beach. In conjunction with sustainability consultant DMV KEMA Engineering, SmithGroupJJR designed a high-performance, open work environment that could support DPR’s full-time staff as well as the large percentage of field employees who spend less than one hour per week at the office.
Key sustainability features include:
-82 daylighting Solatubes® to reduce artificial lighting by 72 percent;
-an 87-foot-long, zinc-clad solar chimney and four evaporative cooling towers to passively cool the building;
-81 operable windows along the north and east facades that automatically open and close in response to climactic conditions;
-a photovoltaic system atop a parking canopy that shades 37 cars and generates enough electricity to offset annual energy use;
-horizontal shading devices to minimize direct solar gain;
-and a “vampire shut-off switch” that disconnects 90 percent of plug-loads at the end of the day to reduce phantom draw.
“One can say, ‘I want a net zero energy building,’” notes Mark Roddy, AIA, LEED AP BD+C, SmithGroupJJR design principal, “but in reality, you have to introduce some pretty innovative strategies to make it happen.”