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Phius Certified Trades Professional - Enclosure Specialist Training | Feb 2027 | Albany, NY
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Project 2034

Red Willow Apartments

VY Architecture

Seattle, Washington

Building Function

Multifamily
Project Type

New Construction
ASHRAE Climate Zone

4C - Mixed - Marine
Construction Completion

2023
Status

Certified
INT. Conditioned Floor Area

9717 ft²

Core Project Team

Phius Certified Verifier

Cybil Tribie
Phius CPHC (Lead)

Dan Whitmore
Project Submitter

Dan Whitmore

Project Information

- Developer
  
  Red Door Sustainable Housing
- Architecture Planning
  
  VY Architecture
- Building Owner
  
  Red Willow Residences LLC
- Mechanical Systems Designer
  
  Staengl Engineering
- Additional Consultants
  
  Gary Klein Associates
- Construction Company
  
  Cascade Built LLC
- Building Function
  
  Multifamily
- Project Type
  
  New Construction
- Construction Type
  
  Wood-Frame
- Number of Units
  
  12
- Number of Stories
  
  3
- Program Version
  
  Phius ZERO 2021
- All Electric
  
  Yes
- INT. Conditioned Floor Area
  
  9717 ft²
- Gross Floor Area
  
  9950 ft²
- Market Category
  
  Affordable Housing
- Status
  
  Certified
- Design Certification
  
  January 28, 2022
- Final Certification
  
  November 2, 2026
- Construction Completion
  
  2023
- ASHRAE Climate Zone
  
  4C - Mixed - Marine
- Region
  
  Northwest

Performance

- Annual Heating Demand
  
  2.95 kBTU/ft².yr
- Annual Cooling Demand
  
  0.89 kBTU/ft².yr
- Peak Heating Load
  
  3.51 kBTU/ft².yr
- Peak Cooling Load
  
  1.41 kBTU/ft².yr
- Site Energy Use Index (EUI)
  
  17.22 kBTU/ft².yr
- Site Energy Use Index (w/Renewables)
  
  -2.25 kBTU/ft².yr
- Compliance Software
  
  WUFI Passive
- Source Energy (Residential)
  
  2675 kWh/person.yr

Enclosure

- Wall 1 Type
  
  All Insulation within Framing
- Wall 1 Insulation Type
  
  Fiberglass
- Roof 1 Type
  
  Vented Below Deck
- Floor Type 1
  
  Slab on Grade
- Floor 1 Insulation Type
  
  EPS
- Floor Type 2
  
  Overhang Floor
- Floor 2 Insulation Type
  
  EPS, Fiberglass
- Window Manufacturer 1
  
  Euroline
- Window Manufacturer 2
  
  Simpson
- Window Manufacturer 3
  
  PlastPro

Systems & Equipment

- Ventilation System Manufacturer
  
  Zehnder & Panasonic
- Ventilation System Layout
  
  Semi-Centralized
- Ventilation System Type
  
  HRV
- Measured Ventilation Fan Efficiency
  
  0.47 W/cfm
- Heating System Manufacturer
  
  Ephoca
- Cooling System Manufacturer
  
  Ephoca
- Hot Water System Manufacturer
  
  AO Smith & Sanden
- Hot Water System Type
  
  Heat Pump Water Heater
- Range Hood Type
  
  Exhaust
- Dryer Type
  
  Non-Vented
- Renewable Energy Type(s)
  
  On-Site PV
- Renewable Energy Annual Production
  
  53749 kWh/yr
- Renewable Energy System Size
  
  50.8kW