POSTED: 04:00 AM PDT Tuesday, April 28, 2009
BY SAM BENNETT
Dan Carter/DJCMilos Jovanovic's newest project will be called the Shift House. The name represents the architect's belief that the next level beyond the Leadership in Energy and Environmental Design system is the Passive House.
"Passive House is a paradigm shift for us," said Jovanovic, co-owner of Root Design Build of Portland. "Rather than finding more efficient ways to heat and cool a house, it dramatically reduces the need for energy."
Jovanovic and several team members from Root Design Build recently finished schematic design on the Shift House in Hood River. He said he and his team, which last year completed design and construction on a LEED platinum home in Portland, are taking lessons from the LEED system to build the first Passive House on the West Coast.
The Passive House system, developed in Germany, creates a nearly airtight interior environment so heat or cool air will not escape. The system uses highly efficient windows, airtight construction, advanced insulation and a heat recovery ventilator – slashing a building's energy consumption by 70 percent, according to the Passive House Institute U.S.
The slow economy means less work for home builders, but that's a welcome development for Jovanovic, who said it gives him more time to focus on designing and building the Shift House. A crucial element to completing the design, he said, was purchasing (for $270) energy modeling software from the Passive House U.S. Institute in Illinois.
"We are using the energy modeling software to guide us the whole way," he said. "The building envelope challenge is to find ways to build the walls and ceiling to be airtight and with no thermal bridges," said Jovanovic. "Creating solid connections without thermal bridges around the windows, doors and foundations is the biggest challenge."
The Passive House system relies on super-insulated windows, as well as insulation with an R value of 50. The Shift House's walls will use foam-insulated panels with plywood on both sides. The heat recovery ventilator system will recalculate air inside the home, without losing heat.
The Shift House will use one solar panel to heat hot water and run a radiator, but the house won't require a furnace. The home will also be oriented to pick up southern sun exposure.
"What our model is showing is that we need thinner walls than the Midwest and thicker than California," he said.
A handful of Passive Houses have been built in the United States, including in Martha's Vineyard, Mass., and Urbana, Ill., where the Passive House Institute U.S. (PHIUS) is located. PHIUS is the official certifier of Passive Houses in the United States.
The official headquarters is the Passivhaus Institut in Darmstadt, Germany. In Europe, there are more than 15,000 structures built to Passive House standards – mostly in Germany and Scandinavia.
A separate garage adjacent to the Shift House will have a green roof. Jovanovic said he was unsure if the home will have a rainwater harvesting system, because of the extra expense and the fact that he wants to pour the majority of the money for the home into the Passive House systems. He said the Passive House will cost about 10 percent more than a traditional home and be completed by November.
"It's exciting to get this built," he said. "We feel it's such a new concept, and clients and people interested in Passive Homes will need to have one of these as a showcase so people can see it's possible."
