of the Portland Tribune.
Jeremy Brooks, a Walsh Construction superintendent on the Orchards at Orenco apartment project in Hillsboro, posted a sign in his trailer that reads “Nothing on this job is typical.”
That’s not an overstatement.
When Orchards at Orenco opens in 2015, it will be the largest passive-house building in North America. The 57-unit Phase 1 is being built to the superinsulated standards of the movement that began in Europe as “passivahus” and is slowly spreading to energy hog America.
Passive house projects built in the Portland area typically are higher-end single-family homes. But Orchards at Orenco is being built by Portland’s Reach Community Development, a nonprofit housing developer that hopes to rent the apartment units for $611 to $733 a month.
Heating bills will be minimal, since passive houses use the highest-known standards in energy efficiency. The airtight membrane at Orchards will be two to three times tighter than normal.
A passive house lives and dies by its insulation. Architects and construction workers must minimize drafts and thermal bridges — metal pipes or other components that can transfer heat quickly between inside and outside. Installing one leaky window here could be a disaster in terms of wasted energy. Catching it and fixing it could be very costly, so quality control is key, according to Brooks.
Costs higher
Orchards at Orenco will cost 11 percent more than traditional construction, according to project architect Michael Bonn, of Ankrom Moisan. The added costs come from a mix of labor and materials, including a sophisticated ventilation system to assure air flow.
Where the Tyvek has been stapled, it must be taped over with Siga Wigluv, a high-tack tape that costs $75 a roll. And Bonn chose stainless steel flashing over cheaper steel.
“The brick will last 200 years, but if you use normal steel flashing it starts to rust in 25 years. Then you have to peel off the expensive brick to get to it, and that’s a cost.”
Dylan Lamar, a passive house consultant with Green Hammer who is working on the Orchards Phases 1 and 2, says the scale of this project is unlike anything he’s seen. Much of the extra cost comes from the windows, doors and the heat recovery system, Lamar says, but the extra cost is worth it.
Inside, men in orange hoodies pull wire, and wobble lights cast a deep shadow on the wall studs. These fir planks are 2-by-10s instead of 2-by-6s, deep enough for twice as much wall insulation. The insulation is blown in with a hose so it gets around every pipe, wire and electrical box. It’s held in place by a plastic film that functions like Gore-tex, letting moisture through so it doesn’t build up in the walls and form mold.
A continuous layer of mineral fiber insulation, 1.5 inches thick, wraps the entire building like a sleeping bag. This green, felt-like material sits on top of the plywood shell, and is hydrophobic, meaning it repels any water that may sneak in, unlike fiberglass.
Reach will rent the units to those earning 30 to 50 percent of area median family income, or $15,240 to $25,700 for a single-person household.
The target niche is “workforce housing,” says Laura Recko, Reach’s fundraising and public relations director. Those are local Hillsboro folks who work in support of the otherwise high-earning Washington County residents, such as the food-service workers at chip plants and shelf stackers at New Seasons.
“We literally walked the neighborhood after the groundbreaking, informing the community,” Recko says.
Tenants will get unprecedented savings on their energy bills, but “there’s going to be some behavioral adjustments,” Recko says.
For example, with no electric air conditioning, tenants will be advised to open their windows at night in the summer to flush out the warmer air. Inside the main entrance, the central staircase is conspicuous, so people might prefer it to the elevator. There also will be a large TV screen showing each unit’s energy use. This could be seen as an invasion of privacy, but Reach hopes to turn it into a game, with a prize for the thriftiest energy user every month.
A hair dryer will do
Passive house insulation is so good, Bonn says, that using a hair dryer can keep a room warm for hours. “Depending on plug load, you may never have to run (an electric) cove heater.”
By plug load he means those discretionary appliances beyond the fridge and stove. “We think people who watch a lot of TV or have a big gaming PC or a DVR will likely never turn on their heat,” Bonn says.
Phase 2 of the development, right next door, will not have a big enough budget to be passive house-certified. “We’re calling it passive lite,” Recko jokes.
The state has cut the budget for affordable housing, so Phase 2 will have smaller units and be a rectangle rather than L-shaped, thus reducing the surface area of the envelope. Phase 3 will be townhouses.
The pressure already was on to reduce the cost of passive house building, which required things like triple-paned windows with complicated cavities in the frames for insulation, and the energy recovery ventilator. That contains a heat wheel, a ceramic wheel about 4 feet across and 3 inches thick, which spins and warms incoming air in winter and cools it in summer. Since the outside and inside air masses don’t touch, annoyances like fish smells don’t circulate through the building.
“A less-expensive mechanical system would just blow the air out the side of the building,” Bonn says. All the same, he had to fight to buy a North American energy recovery ventilator and get it passive house-certified, rather than use an even more expensive one from Europe.
Building an affordable passive house project was the idea of Reach’s previous Executive Director Dee Walsh (no relation to Walsh Construction), now at Housing Partnership Network. Walsh discovered passive houses and wrote into Reach’s mission that they would be doing them by 2015.
Ankrom Moisan wanted to get involved in passive house building, Bonn says. “We like to be out in front of the high-performance movement.”
He knows of only one U.S. apartment building in Pennsylvania and another one in New York built to passive house standards, but neither are this big.
“When it comes to affordable housing, 11 percent is such a good investment,” Lamar says. “We just finished a cost study, and from Day One the tenants’ utility bills will be 50 percent less than average, and Reach’s bills for hot water, sewer, water and trash will be 38 percent less.
“It’s a quality building, good for the next 100 years without retrofits.”
Link to the article.