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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!
Upcoming Sessions
- Member Office Hours - Projects
  December 9
- Jan. Webinar: Walking Through METr
  January 13
- Phius Certified Builder Training and Certification Exam | January 2026
  January 20 – 30
- Phius Certified Consultant Training & Certification Exam | January 2026
  January 20 – 30
- Policy Work
  Promoting policies designed to grow passive building
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  Providing the tools you need to create healthier buildings
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Project 1955

Lake Bosworth Passive House

VELOCIPEDE architects inc

Snohomish, Washington

Building Function

Multifamily
Project Type

New Construction
ASHRAE Climate Zone

4C - Mixed - Marine
Construction Completion

2025
Status

Certified
INT. Conditioned Floor Area

2482 ft²

Core Project Team

Phius CPHC (Lead)

John Novak
Phius Certified Rater

Tom Balderston
Project Submitter

John Novak

Project Information

- Architecture Planning
  
  VELOCIPEDE architects inc
- Building Owner
  
  Tristine Samberg & Michael Hablewitz
- Mechanical Systems Designer
  
  Cascade Energy Services
- Construction Company
  
  Lastingnest inc
- Building Function
  
  Multifamily
- Project Type
  
  New Construction
- Construction Type
  
  Wood Frame
- Number of Units
  
  2
- Number of Stories
  
  2
- Program Version
  
  PHIUS+ 2018
- All Electric
  
  Yes
- INT. Conditioned Floor Area
  
  2482 ft²
- Status
  
  Certified
- Design Certification
  
  September 23, 2022
- Final Certification
  
  July 11, 2025
- Construction Completion
  
  2025
- ASHRAE Climate Zone
  
  4C - Mixed - Marine
- Region
  
  Northwest

Performance

- Annual Heating Demand
  
  7.14 kBTU/ft².yr
- Annual Cooling Demand
  
  1.75 kBTU/ft².yr
- Peak Heating Load
  
  3.07 kBTU/ft².yr
- Peak Cooling Load
  
  2.1 kBTU/ft².yr
- Site Energy Use Index (EUI)
  
  14.17 kBTU/ft².yr
- Site Energy Use Index (w/Renewables)
  
  1.29 kBTU/ft².yr
- Compliance Software
  
  WUFI Passive
- Source Energy (Residential)
  
  4810 kWh/person.yr
- Source Energy (Residential w/Renewables)
  
  437 kWh/person.yr
- HERS Rating
  
  45
- HERS Rating w/Renewables
  
  9

Enclosure

- Wall 1 Insulation Type
  
  Fiberglass
- Window Manufacturer 1
  
  Unilux

Systems & Equipment

- Ventilation System Manufacturer
  
  Brink
- Measured Ventilation Fan Efficiency
  
  0.34 W/cfm
- Heating System Manufacturer
  
  Misubishi
- Cooling System Manufacturer
  
  Mistubishi
- Hot Water System Manufacturer
  
  SanCO2
- Renewable Energy Type(s)
  
  On-Site PV
- Renewable Energy Annual Production
  
  9371 kWh/yr
- Renewable Energy System Size
  
  10.5kW