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The team managing an ambitious green building project in Yamhill County is navigating three demanding certification systems, and finding overlaps and conflicts among them that it contends will benefit the rest of the building community.

The Karuna House is designed to meet standards for Leadership in Energy and Environmental Design for Homes platinum, and , a rating for a Swiss certification system. While the three standards share many similar aims, the combination is requiring some creative and complex building solutions.

鈥淚t’s been challenging,鈥� said Cory Hawbecker, project manager for . 鈥淭here’s a lot of alignment between them, but each has its own emphasis, so it’s taken a lot of work to make sure we have all of our bases covered.鈥�

While Passive House focuses almost exclusively on extreme energy efficiency, LEED addresses design and materials. Meanwhile, the Minergie system is new to the project team 鈥� the Karuna House could in fact be one of the first buildings in the U.S. to earn the certification.

鈥淲here LEED falls short, Minergie picks up the slack, and Passive House has no requirements for material use 鈥� you can things that are awful for the environment as long as you meet the energy standards,鈥� Hawbecker said. 鈥淗olistically, (the Karuna House) will perform to the highest level in all of the different categories.鈥�

The Minergie system offers a basic level of certification, but the Karuna House is shooting for Minergie-P-ECO, its most stringent standard. The 鈥淧鈥� signifies very low energy consumption and the 鈥淓CO鈥� means the project will meet extra ecological requirements, including noise protection for occupant comfort and life-cycle analyses on building materials.

The client, who requested to remain anonymous, first read about the Minergie system in an MIT publication, according to Hawbecker. The Minergie standard is not available in North America yet, so the client wanted to help introduce it with this project 鈥� near a Yamhill County vineyard.

After engaging in an 鈥渆co-charette鈥� with the designers and builders from Hammer and Hand, the team decided to move forward not only with the Minergie standard, but also LEED and Passive House.

鈥淎t the time it struck me that there would be a very narrow path to follow,鈥� said Sam Hagerman, president and co-owner of . 鈥淎nd there are existing disagreements between the standards.鈥�

For example, the Passive House model requires a ventilation system that conflicts with the one cited by LEED.

The Karuna House design also conflicted with a building code requirement for radon-resistant systems. To meet the code, the team would have had to punch several holes in the building envelope, and undermine the extreme air tightness Passive House requires. However, the project team successfully proved that the design accounted for potential radon exposure through alternative measures.

Several common construction products and building materials were untenable because of the suite of certifications. Minergie-P-ECO prohibits site-applied foam because it can expose the installer to harmful chemicals.

鈥淲e don’t like to use it anyway, but being able to apply spots of spray foam on-site can be a good Band-Aid when no other product will work,鈥� said Dylan Lamar of , the Passive House energy consultant for the project.

The team is relying on precise carpentry to reduce the need for any gap-filling product, but it has switched to an expanding foam tape to meet the guidelines.

Three certifications come with a high price tag. The client declined to divulge the project’s total budget; however, third-party consultants were hired for each certification, and such measures can cost tens of thousands of dollars.

The Minergie system was the most expensive to incorporate, in large part because it is new to the U.S. The standard was translated into English, engineers in Europe were hired to help with the specifications and, according to Hawbecker, the only qualified Minergie energy consultant in the U.S. is based in Minneapolis, Minn.

Because of unique project technicalities, Hagerman hopes to cycle different Hammer and Hand workers onto the site every few weeks. The project, for instance, includes a wind turbine, which is expected to provide more energy than the house will consume.

鈥淭here’s so much building science and detailing up there that it’s good for everyone to get exposed to it,鈥� Hagerman said. 鈥淎nd we hope the impact of the job is shared not just in the local community, but in the high performance, low-energy building community nationally and internationally through the web.鈥�

Hammer and Hand plans to post weekly updates on with technical videos and project updates.

In addition to green elements, the client also wanted an attractive home with specific features, including a deck on the roof.

鈥淯sually these buildings with high technical standards have a way of looking like they’re designed by technicians,鈥� Lamar said. 鈥淏ut this is a demonstration of how you can achieve high aesthetic standards and still have a very high-performing building.鈥�