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December 1 – January 16

Phius Certified Trades Professional - Enclosure Specialist Training | December 2025 & January 2026 | Portland, OR
Become a Phius Enclosure Specialist!
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  December 9
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  January 13
- Phius Certified Consultant Training & Certification Exam | January 2026
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  January 20
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Passive Building
- What is Passive Building?
  Your passive building questions, answered
- Sectors
  Passive isn't just for houses
Certifications
- Projects
  Phius Certified Projects are the most energy efficient and comfortable buildings in the world
  Find a Project
- Products
  Phius Certified Products are guaranteed to perform to passive standards
  View Products
- Professionals
  Phius Certified Professionals are on the cutting edge of high-performance building
  Find a Professional
Standards
Our Approach
- New Construction
  Phius CORE and Phius ZERO provide the path for constructing a Phius building from the ground up.
- Retrofit
  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.
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Categories
Upcoming Sessions
- Member Office Hours - Projects
  December 9
- Jan. Webinar: Walking Through METr
  January 13
- Phius Certified Consultant Training & Certification Exam | January 2026
  January 20 – 30
- Member Office Hours - METr
  January 20
December 1 – January 16

Phius Certified Trades Professional - Enclosure Specialist Training | December 2025 & January 2026 | Portland, OR
Become a Phius Enclosure Specialist!
Resources
- Policy Work
  Promoting policies designed to grow passive building
  Policy Database
- Tools and Support
  Providing the tools you need to create healthier buildings
  Resource Library
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Calculator/Tool

Transom Heat Pump Water Heater COP Estimator v25.1.0

Use this estimator to determine a climate-adjusted coefficient of performance (COP) for the Transom Heat Pump Water Heater. This estimator is applicable for the V105, V210 and V420 models.

August 29, 2025

By Phius Certification Team

VIEW AND DOWNLOAD CALCULATOR HERE