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Project 2408

Bellewood Farms Guest Cottage

Whitney Architecture

Bellevue, Washington

Building Function

Single-Family
Project Type

New Construction
ASHRAE Climate Zone

5C - Cool - Marine
Status

Certified
INT. Conditioned Floor Area

2313 ft²

Core Project Team

Phius CPHB

Ryan Lurie
Phius CPHB

Benjamin Toda
Phius Certified Rater

Tom Balderston
Phius CPHC (Lead)

Leslie Lane
Project Submitter

Leslie Lane

Project Information

- Architecture Planning
  
  Whitney Architecture
- Building Owner
  
  Allison Light & Geoffrey Landskov
- Mechanical Systems Designer
  
  Balance Construction Consulting
- Additional Consultants
  
  Geotech Consultants, Inc | Carter Quinn Norlin | Plog Engineering | ABC Herron Tree | Cambium, Inc | Balderston Associates, LLC | HL Engineering
- Construction Company
  
  Triple Bottom Line Construction
- Building Function
  
  Single-Family
- Project Type
  
  New Construction
- Construction Type
  
  Wood-Frame
- Number of Units
  
  1
- Number of Stories
  
  3
- Program Version
  
  Phius CORE 2021
- All Electric
  
  Yes
- INT. Conditioned Floor Area
  
  2313 ft²
- Status
  
  Certified
- Design Certification
  
  June 27, 2025
- Final Certification
  
  November 3, 2026
- ASHRAE Climate Zone
  
  5C - Cool - Marine
- Region
  
  Northwest

Performance

- Annual Heating Demand
  
  6.08 kBTU/ft².yr
- Annual Cooling Demand
  
  1.11 kBTU/ft².yr
- Peak Heating Load
  
  4.09 kBTU/ft².yr
- Peak Cooling Load
  
  1.93 kBTU/ft².yr
- Site Energy Use Index (EUI)
  
  11.66 kBTU/ft².yr
- Compliance Software
  
  WUFI Passive
- Source Energy (Residential)
  
  2845 kWh/person.yr
- HERS Rating
  
  52

Enclosure

- Window Manufacturer 1
  
  Cascadia
- Window Manufacturer 2
  
  Fenstur

Systems & Equipment

- Ventilation System Manufacturer
  
  Zehnder
- Measured Ventilation Fan Efficiency
  
  0.52 W/cfm
- Heating System Manufacturer
  
  Mitsubishi
- Cooling System Manufacturer
  
  Mitsubishi
- Hot Water System Manufacturer
  
  Sanden
- Hot Water System Product Name
  
  SanCO2