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  Phius standards aren't just for residential buildings. Phius CORE COMM and Phius ZERO COMM can be applied to any non-residential building.
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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 2021 Performance Criteria Calculator

This calculator is used to determine project-specific performance criteria for Phius 2021 Certification. Only available for projects with Phius contract dates before September 1, 2025.

Phius 2021 Criteria Calculator

This calculator, updated on January 12, 2026, is used to determine project-specific performance criteria for Phius 2021 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.

Open the Phius 2021 Criteria Calculator

Go to the PHIUS+ 2018 Criteria Calculator Instead

Find Out Which Version is Applicable to Your Project

Go to the Phius 2024 Performance Criteria Calculator Instead