When Passive House Institute U.S. launched its first training program in 2008, the Eugene, Oregon–based architect Jan Fillinger proved a natural sign-up. The Swiss-born founder of STUDIO-E Architecture kept Ed Mazria’s The Passive Solar Energy Book as a desktop bible during his student years at the University of California at Berkeley, and he has pursued sustainability in general since his first day of practice.
Photo © Mike Dean Photography
“I fell in love with the Passive House approach the moment I learned about it, because it is the most effective way I have ever encountered to achieve the highest level of energy efficiency,” Fillinger says. “[Passive House Institute U.S.] also has a modeling system that allows you to fine-tune systems and assemblies to that sweet spot where you get the most bang for the dollar spent.”
The convert tried applying these new tools into projects just as quickly, including a residence for Tim Gift and Sarah Peterman near Eugene that had been mostly designed. “Because we were into design systems at this point, we tried to incorporate as many techniques into it as we could,” Fillinger says. To reduce thermal bridging, for example, he substituted his typical batt or blown insulation for exterior rigid insulation on the roof and floor. The building’s walls were thermally broken at the time of the Passive House adaptations, thanks to Fillinger’s configuration of two double-stud walls on an 11.25-inch base.
To be sure, Fillinger had already transformed Gift and Peterman into formidable champions of sustainable design. The software engineer and artist allowed STUDIO-E to complete the three-bedroom, three-bath main house after design and construction of a garage and 2,830-square-foot studio, so that this final puzzle piece was optimized for solar heat gain and energy efficiency. The clients also determined that the bluff-top structure would include both solar domestic hot water and a ground-source heat pump connected to radiant floors. Finally, a Swiss-manufactured Zehnder heat recovery ventilation unit impacts heating and cooling, by continuously filtering fresh air into the house without sacrificing interior temperatures.
Of the HRV, Fillinger advocates the system both for climate control and occupant health. “These are tight homes that often have a lot of human-made materials, which are not necessarily in their virgin state. We still don’t know everything about VOCs and toxic products. Even when we use what are touted as low-VOC products, we don’t know everything about the byproducts that can sometimes result from combining seemingly harmless building materials.”
Besides filtering these unknowns through the HRV, Fillinger says this project precludes most of them right from the start. Indeed, all three buildings on Gift and Peterman’s 30-acre site were developed to maximize repurposed, recycled, non-toxic, sustainably harvested, and durable materials. Prime examples are cabinetry and a floating staircase’s treads, both of which are made from a black oak felled by a windstorm on the site four years earlier. That material melds poetically with recycled steel beams, natural plaster surfaces, and kitchen countertops recycled from the lanes of a former bowling alley. Similar combinations are seen outside, with cement-fiber panels and corrugated metal juxtaposed to recycled cedar barnwood siding that reveals patina, graffiti, and barn paint.
In addition to Passive House thinking, the main house incorporates lessons from the two previous volumes that STUDIO-E had created for the couple, who have one daughter. Fillinger corrected a detail in a sunshade that he first mounted to the studio, and he specified a thicker sheet metal for the gutters to avoid oil canning. The contractor SixDegrees Construction kept both architect and homeowners engaged in every aspect of the construction process, in order to stay focused on the changes that could boost quality.
Gift and Peterman have gotten into the spirit of improvement as a result, making some tweaks of their own. Fillinger recalls, “We used the lowest-cost fluorescent lamps you can find, and they didn’t recess them in the studio, which causes some glare. In the house we embedded them in slots we created between the floor joists, and the light is really nice and unobtrusive.” The owners are continually learning, too. The evacuated solar tubing, as well as a 5-kilowatt photovoltaic array and other systems, report to their smartphones, so they can monitor how the house behaves under different conditions.