Hood River Middle School (photo by Michael Mathers)
BY BRIAN LIBBY
Since it began in 1997, the American Institute of Architects Committee on the Environment's annual Top Ten Green Projects list has been the highest honor a sustainable building project can achieve. Though Portland seemed to be an industry leader, for much of the past 15 years there have not been many projects by local firms to crack the list until ZGF's Twelve West finally did so in 2010 (although GBD Architects' Gerding Theater was an honorable mention in 2007).
This year, however, Portland is dominating the list, with three projects by Rose City firms in the just-announced Top Ten for 2012: the Mercy Corps headquarters in Old Town, designed by THA Architecture; Hood River Middle School, designed by Opsis, and the Portland Community College Newberg Center, designed by Hennebery Eddy. Maybe it helped having local architect Clark Brockman of SERA Architects on the six-person jury, or perhaps the fact that two of the three honored projects achieve net-zero energy usage was more of a factor. Regardless, this should help cement the city's status as a national sustainable design leader.
Mercy Corps headquarters (photos by Jeff Amram)
The Mercy Corps building occupies a prominent position along the Willamette riverfront, on Naito Parkway at the west edge of the Burnside Bridge. THA expanded the historic Packer-Scott building to go from 42,000 to 85,000 square feet. There's a green roof atop the building, and eventually there will be an array of solar panels operated and studied by students at the University of Oregon's Portland campus next door.
Mercy Corps received a top-level LEED Platinum rating, as well as a very low EUI (energy use intensity) score of 36, less than half the average of an office buiding. Potable water use was also reduced by 40 percent compared to a space designed to code specifications.
The PCC Newberg building is the first structure in what will eventually be a 15-acre multi-building campus. It is constructed from structurally insulated panels (SIPs) that reduce heat loss from thermal bridging and air infiltration. The buildinng is naturally ventilated with louvers and double dampers to prevent drafts. As reported in Eco-Structure, "When outside temperatures dip below 55 F, heat-recovery ventilators condition fresh air, and the concrete slab circulates 90 F water through a closed-loop radiant system in the slab that then radiates heat to the building occupants. In warmer months, ceiling fans provide a 3 F drop in ambient temperature and use a fraction of the energy of a traditional air-conditioning unit. A 109-kilowatt rooftop PV array meets the center’s remaining energy needs."
Hood River Middle School (photos by Michael Mathers)
Opsis Architecture's design for Hood River Middle School's new Music and Science Building is also net-zero for energy, thanks largely to its exterior envelope, be it well-insulated walls, triple-glazed windows, or detailing that prevents thermal bridging.
The main entrance, as Eco-Sructure also explains, "is purposefully sited at the inside corner of the building so that the mass of the concrete walls and a concrete slab shelter the entrance against winds from the Columbia Gorge. The thermal mass also buffers the interior spaces against seasonal temperature swings. Also contributing the net-zero-energy status is a tight envelope, a geothermal heating system, heat-exchange recovery ventilators, a radiant-heating system in the slab, and a 35-kilowatt solar PV system on the roof."
Besides its energy efficiency, all rainwater runoff at the new Hood River Middle School building gets collected and treated in a new bioswale, then is stored in a 14,000-gallon underground cistern, and then reused for irrigation in the student garden. All told, some 123,000 gallons of water will be saved annually. As someone raised in the next town over from Newberg, McMinnville, all I can say is I wish the rest of this town's architecture, infrastructure and planning were of an equal design caliber to the PCC facility.