Achieve Phius CORE

Phius' most prominent performance standard, Phius CORE is rooted in passive building concepts and best practice. It sets the industry standard baseline for net-zero building design.

The Phius CORE standard utilizes a three-prong framework:

Co-Requisite Programs & Other Quality Requirements

For residential projects, the Phius standard builds upon 3rd party programs such as ENERGY STAR, EPA Indoor airPLUS, and DOE Zero Energy Ready Home. These well-respected programs provide a baseline quality framework for design and construction inspection.

Download the Single Family Quality Assurance Workbook

Space Conditioning Load Limits

The Phius standard sets performance thresholds to regulate investment in passive conservation strategies. Targets are set on for annual loads both peak and annual loads. Reduced peak loads provide comfort, thermal resilience during power outages, and reduced mechanical system sizes. Reduced annual loads provide lower annual operating costs for the building. Project-specific targets can be calculated using the Phius 2024 Performance Criteria Calculator.

Open the Phius 2021 Performance Criteria Calculator

Source Energy Use Limit

Source Energy is Phius' metric used to assess the total energy use of the building. Source energy takes into account the amount of energy required to provide energy to a building site including losses in extraction, production, and transmission. The Phius CORE net source energy limit varies based on building size and occupant density and can be calculated using the Phius 2024 Performance Criteria Calculator.

Open the Phius 2021 Performance Criteria Calculator

Phius CORE provides

Comfort

Superinsulation, high performance windows and efficient mechanical systems create a comfortable, quiet building

Safety

Phius-certified buildings go through a rigorous quality control process, ensuring safety for the environment and the building inhabitants.

Affordability

Phius projects require minimal to no additional upfront costs, while guaranteeing substantial energy cost savings in the future.

Resilience

Phius buildings have been proven to be more resilient in the event of natural disasters, such as wildfires and extreme heat and cold events.

Long-Term Durability

The holistic design of Phius buildings and attention to detail in the enclosure make them uniquely built for the long haul.

Health

Superb indoor air quality is a prerequisite for Phius certification – you can count on a healthy environment.