HKP Architects
Mount Vernon: (360) 336-2155
Seattle: (206) 686-2505


The certifying organization in the U.S. for Passive House building is Passive House Institute U.S. (PHIUS). A Passive House certified building can be designed by anyone, but PHIUS recommends that a Certified Passive House Consultant (CPHC®) participate in the design process. A CPHC is a qualified design professional that has undergone extensive training in Passive House design principles and passed a rigorous examination. In some cases the building designer is also a CPHC. For the best results the CPHC is involved early in the process to keep the project aligned with the PH principles that will ultimately be required for certification.

Documentation of the building is evaluated by PHIUS for precertification in the PHIUS+ Certification program prior to construction. The (+) in PHIUS+ signifies that in addition to the thorough Passive House design verification protocol, a stringent Quality Assurance and Quality Control (QA/QC) program was performed on site by highly skilled and specialized PHIUS+ Raters.

Buildings may also be internationally certified by Passive House Institute (PHI) based in Germany under a similar process, but this does not include on-site QA/QC verification of construction.

The benefits of PHIUS+ Certification include:

Comprehensive Design and Energy Model Review

Passive House buildings in North American climates present unique design challenges; small mis-steps can lead to big problems. PHIUS+ certifiers are the most experienced Passive House professionals in North America. They thoroughly review projects at the design stage, identify problems, and work with project designers to find solutions to meet the criteria for Certification.

Rigorous Quality Assurance

Project testing and inspections are conducted by experienced Home Energy Raters (HERS Raters), trained by PHIUS to work on PHIUS+ projects. The on-site inspections and testing help to assure PHIUS, the project teams and the building Owners that the buildings will perform as designed.


Most projects will automatically receive a Residential Energy Services Network (RESNET) HERS Index score as part of certification. The RESNET HERS Index is the leading industry standard by which a home’s energy efficiency is measured. Many local, state, and federal financial incentive programs require a HERS Index to demonstrate compliance.