A Co-op of North American Passive House Professionals

dedicated to quality, accessibility, and affordability. 

We have joined together and formed CertiPHIers Cooperative to support the growing North American Passive House Industry.    We are creating the model for the growing industry to be supported in certification and education by local owner/member practitioners in the authentic North American style of the "producer cooperatives."    

Our motto: "Better Together."


Producer Cooperatives are uniquely American.

As a Cooperative, we support affordable, local service. The early development of much of North America was accomplished by people experiencing a common need and then pooling their local resources to accomplish large tasks. It's the same with Passive House development.

We see a growing industry needing increased access to efficient and affordable building certification to the international Passive House Standard. We see a need for more educational opportunities and more tools that can be used by local practitioners in local units.

CertiPHIers met this need by locally developing a full translation of the Passive House Planning Package v8 in American Inch/Pound units (PHPP v8.5).


Tools for Everyone (TFE)

CertiPHIers Cooperative's TFE initiative supports growth by making what Passive House designers need: - Tools and Education - available at the lowest possible cost.



Why a partnership with the Passive House Institute?

CertiPHIers Cooperative has a long-standing partnership with Dr Wolfgang Feist and the Passive House Institute (PHI).   Our members helped build regional, national, and  international Passive House networks, created PHPP translation tools and "how to" books & software, and volunteered hundreds of hours organizing Passive House conferences.  

Based on that successful collaboration, PHI invited us to begin certifying buildings.  Naturally, we accepted.  CertiPHIers recognizes Dr. Feist's 27 years of intellectual leadership and PHI's 20 years of experience, research, and development.  PHI is the first and oldest Passive House Institute in the world.  And the internationally-acknowledged leader.  

Our association with PHI will expand North America's access to the PHI's expertise.  That's why we included the PHI in our name!  

You have choices in building standards and building certifiers.  We hope you'll choose CertiPHIers.



Meet the CertiPHIers


Tad Everhart CPHC, PHI accredited certifier, Owner, Tad Everhart Energy Advisor LLC, CertiPHIers' President

Tad was hooked on passive the moment he read about it, signed up immediately for PHIUS’ inaugural class in May, 2008, and because a Certified Passive House Consultant in January, 2009.  Tad has donated his skills from 25 years as a trial lawyer and corporate counsel to supporting Passive House organizations.  Tad organized the first meetings of local “passivists” in Portland, Oregon in 2008, then volunteered as Secretary on the first PHIUS board of directors in 2009.   In 2010, Tad collaborated with the founders of Passive House Northwest and served as a board member since 2012.  Tad was one of the founders of the North American Passive House Network in 2011 and local organizer for the Network’s many successful speaker tours.  Tad and his brother developed, designed, and built 40 homes in the Portland area including his family’s home, completed in 1998—inconveniently 10 years before discovering Passive House.  In August, 2009, Tad’s family embarked on a journey to “future-fit” their home  to the Passive House Standard, and today, they are almost ready for certification.  Meanwhile, they enthusiastically participate in the International Passive House Open House Days  with the International Passive House Association and have hosted approximately 1,000 Passive House tourists in 40 organized tours.  Tad is a PHI-accredited building Certifier, he certifies Passive Houses, and he manages CertiPHIers' operations.


Christina Snyder Architect, CPHC, PHI accredited certifier, Equilibrium Energy Spaces

Christina Snyder attended PHIUS' inaugural class in 2008 and became a CPHC in 2009, continuing a career focused on sustainable design, both in practice and education. A residential builder, an architect and sole proprietor since 2002, she also instructed architecture students as an adjunct professor, coaching them through winning the first & second Michigan Zero Energy Home competitions, as well as in competing in the 2007 Solar Decathlon in Washington DC, and has also published a paper on zero energy homes utilizing seasonal heat storage systems.  Christina has been a partner in a renewable energy system installation business, Sustainable Systems, before starting her own architectural practice. She has volunteered on natural building projects including strawbale, cob, cordwood, and thatched structures. And has lectured throughout the Midwest on energy efficiency, Zero Energy Homes, and most recently has taught Continuing Education classes for professionals on Passive Houses.  Christina is also walking her talk; she's almost completed a new Passive House on her family's Southern Michigan farm using an innovative foundation system of glass-fiber reinforced concrete structural insulated panels.  Christina is a PHI-accredited building Certifier, and she certifies Passive Houses.

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Chris Petit CPHD, PHI accredited certifier, Regenerative Design

Chris learned about Passive House and was immediately impressed by the rigor of the systems approach to construction and its commitment to reducing energy use.  Chris' commitment to low-energy buildings stemmed from his love for the environment and his passion to protect natural ecosystems.  Through his research while earning his BA in Biology cum laude from Carleton College, he decided to go beyond reporting about the disheartening trends he was seeing.  He chose to influence the built environment and the way we live, in order to reduce the large impact we currently make on the natural world with the way we design, construct, and operate buildings. 

Chris is a Passive House trainer, consultant, and building certifier accredited by the German Passive House Institute. He has provided design support and energy modeling services since 2008 with the Center for Sustainable Building Research, Clean Energy Coalition and Regenerative Design. Through CertiPHIers Cooperative, Chris has consulted and certified Passive House projects in the US and Canada. In addition to his work with CertiPHIers, Chris teaches sustainable design, renewable energy, thermal bridge modeling, designPH, PHPP, and building energy-efficiency best practices and auditing. He holds a MS in Architecture from the University of Minnesota. Chris became a CPHD through training with the Canadian Passive House Institute-West and completed Certifier training at the Passive House Institute in Darmstadt.


Rolf Jacobson CPHC, PHI accredited certifier, Center for Sustainable Building Research, University of Minnesota

Rolf became a Passive House convert in 2008 after listening to a presentation by Stephan Tanner, designer of the first certified Passive House in North America (the Waldsee Biohaus).  After attending the 3rd annual Passive House Conference in the US, held in Duluth that year, he decided to focus his academic studies on the concept.  For his Masters of Science thesis, Rolf traveled to Norway in 2010 on a Fulbright fellowship to study the building science of Passive House envelopes optimized for cold climates.  While researching there for a year, he used energy and moisture modeling tools such as PHPP, WUFI, and THERM to investigate and comprehensively evaluate a wide range of residential building assemblies and details in Performance of 8 Cold Climate Envelopes for Passive Houses.  Rolf now uses these tools on a regular basis as an energy and enclosure consultant and has worked on a large variety of projects from Passive Houses to commercial buildings.  Rolf also continues to work on exciting new research opportunities as a Research Fellow at the University of Minnesota’s Center for Sustainable Building Research (CSBR).  With project partner NorthernSTAR, the center recently received a $1 million dollar grant from the DOE to help develop and construct a series of homes using a panelized, tilt-up enclosure system (SEP-ETTMS).  This system is modeled on “perfect-wall” principles of moisture safety and routinely achieves Passive House levels of airtightness while reducing construction costs.  Rolf became a CPHC through PHIUS in 2015 and resides in Minneapolis/St. Paul.   


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Dylan Lamar Architect, CPHC, PHI accredited certifier, Green Hammer

Dylan is among the leading Passivhaus consultants in the country, having designed Passivhauses since 2004 from Illinois, to New Mexico, to Oregon. He has translated the PHPP into IP-units, in 2008 and again in 2014. He has worked on many Passivhaus first’s in the nation including office/educational buildings, affordable single-family and the largest multifamily Passivhaus in the US (currently under construction). In 2010 he published Urbanize and Insulate: The Development of a Fossil-Fuel Exit Strategy, which highlights the relationship of Passivhaus toward a larger framework of societal sustainability.

Dylan works as an architect and energy consulting with Green Hammer, a design-build firm in Portland, Oregon,  is a PHI-accredited building Certifier, and assists CertiPHIers with research project and certification of Passive Houses. 


Steve Mann CPHD, PHI accredited certifier, Home Energy Services
Steve has been involved in the construction industry for more than 25 years. His focus is to assist architects, contractors, developers, real estate professionals, and homeowners with sustainable design and high-performance construction practices. His primary activities include design consulting, building and HVAC testing, and sophisticated energy modeling. Steve is the designer and builder of two LEED for Homes Platinum projects. His current project is a LEED and Passive House-certified new home. His current passion is Passive Houses. He was bitten by the bug in 2010. Steve’s certifications include:

  • PHI Certifier, Certified Passive House Designer, Builder, Tradesperson, and PHIUS+ Rater.

  • LEED AP+ Homes and LEED for Homes Green Rater.

  • California-certified HERS Rater, and residential Certified Energy Analyst (CEA).

  • CalCERTS HERS Rater instructor.

  • EPA Energy Star Rater, DOE Zero Energy Ready Homes verifier.

Steve has participated in multiple subject matter expert groups for GBCI, the LEED credentialing authority, and test question writing for the California Certified Energy Analyst examination. A long-time professional writer, he is currently Senior Editor for Passive House Buildings magazine, former Home Energy magazine Contributing Editor, and former President and Board Chair of the California Association of Building Energy Consultants.

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Friends of CertiPHIers


Albert Rooks Owner, Small Planet Supply, CertiPHIers' Past Vice President

Albert became a Passive House enthusiast in 2009 after a long career in building materials. "The opportunity of Passive House is to both refine and excercise my personal enterprise development skills while problem solving assemblies and material requirements that aren't found within our North American supply chains." Albert helped found Passive House Northwest and served on its first board of directors in 2010. He also helped found the North American Passive House Network. Albert is currently a board member of the Northwest Ecobuilding Guild. As President and Founder of Small Planet Supply  Albert has worked with Passivhaus Institut's Dr Wolfgang Feist and staff to import the Institut's scientific studies and create tools for the Passive House Planning Package including the IP version of PHPP v8 for the American market. In 2015 Albert and Eva completed their "Corkhaus" deep energy retrofit of their condo with exterior cork insulation and many other Passive House components. Corkhaus uses cutting edge materials and is under study by two of the Northwest region's leading researchers: RDH Building Sciences for a study of the moisture movement in Thermacork expanded cork facade  and Washington State University for a study of the effectiveness of delivering both domestic hot water and space conditioning through a Sanden Eco System CO2 heat pump hot water heater.  Albert and Eva's Corkhaus in Olympia, Washington is the second home in North America where a single CO2 refrigerant heat pump water heater provides both all domestic hot water as well as all space heating without electrical resistance backup heating.  Albert contributes his marketing, sales, accounting, and small business expertise to CertiPHIers.


Sara Gundermann Small Planet Supply

Sara has been involved in the sustainable building industry for several years, overseeing operations at The Small Planet Supply, a leading distributor of high-performance building products. She also organizes events and workshops to expand the public's knowledge of energy-efficient building practices and products. Being a “health nut” with a background in human physiology and nutrition, Sara understands the important relationship between one’s personal health and their living environment. In her free time, she enjoys working out and competing in fitness competitions, attending concerts, reading, and hiking in the Pacific Northwest.  Sara assists CertiPHIers with financial transactions and reception.


André Harrmann CPHC, Harrmann Consulting / CanPHI-West / NAPHN / iPHA

André holds graduate degrees from German and U.S. universities in engineering and architecture. He is a Certified Passive House Designer (CPHD), a PHI-accredited building Certifier, a Passive House trainer, a board member and Vice Chair of the Canadian Passive House Institute West (CanPHI-West), a board member of the North American Passive House Network (NAPHN), and a member of the International Passive House Association (iPHA).

Through his Harrmann Consulting Andre provides design support, energy modelling and certification services for Passive House projects in Canada. As Project Manager for the University of British Columbia (UBC) he facilitates construction projects to achieve UBC’s energy conservation targets.

André has advised on several single family and multi-unit residential buildings to achieve the international Passive House standard. He is familiar with the latest developments of the standard and has recently compiled all formulas and information relevant for Passive House in a handy compendium available at Harrmann Consulting.