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  Passive isn't just for houses
  
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Our Approach
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  Phius CORE and Phius ZERO provide the path for constructing a Phius building from the ground up.
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  Upgrade existing buildings to Phius standards using Phius CORE REVIVE and Phius ZERO REVIVE.
- Commercial
  Phius standards aren't just for residential buildings. Phius CORE COMM and Phius ZERO COMM can be applied to any non-residential building.
Categories
February 17 – 27

Phius Certified Builder Training and Certification Exam | February 2026
Become a Phius Certified Builder!
Upcoming Sessions
- Phius Certified Verifier Training | February 2026 | Boston, MA
  February 4 – 5
- Phius Project Certification Workshop | February 2026
  February 4
- Feb. Webinar: QAP 101
  February 10
- WUFI Passive Single Family | February 2026
  February 11 – 18
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Calculator/Tool

Phius 2024 Performance Criteria Calculator

This calculator is used to determine project-specific performance criteria for Phius 2024 New Construction projects using WUFI Passive. Projects submitted using METr now have the criteria calculator built into the software directly.

January 12, 2026

Phius 2024 Criteria Calculator

This calculator, updated on January 12, 2026, is used to determine project-specific performance criteria for Phius 2024 Certification. The latest update to this calculator includes a correction for the Dehumidification Degree Day (DDD) used per climate location which now accounts for altitude. In addition, the 'Mechanical Room Temperature' is automatically calculated, which is needed for projects with ventilation devices outside of the thermal envelope.

Open the Phius 2024 Criteria Calculator