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Project 2474

Sato Residence

Takahashi Kenchiku Co., Ltd.

Ogano-Machi Chichibu-Gun, Saitama, Japan

Building Function

Single-Family
Project Type

New Construction
Construction Completion

2025
Status

Certified
INT. Conditioned Floor Area

1305 ft²

Core Project Team

Phius Certified Rater

Sayo Okada
Phius CPHC (Lead)

Shingo Takahashi
Project Submitter

Shingo Takahashi

Project Information

- Architecture Planning
  
  Takahashi Kenchiku Co., Ltd.
- Building Owner
  
  Masato Sato
- Mechanical Systems Designer
  
  Takahashi Kenchiku Co., Ltd.
- Construction Company
  
  Takahashi Kenchiku Co., Ltd.
- Building Function
  
  Single-Family
- Project Type
  
  New Construction
- Number of Units
  
  1
- Number of Stories
  
  2
- Program Version
  
  Phius ZERO 2021
- All Electric
  
  Yes
- INT. Conditioned Floor Area
  
  1305 ft²
- Status
  
  Certified
- Design Certification
  
  February 20, 2024
- Final Certification
  
  April 25, 2025
- Construction Completion
  
  2025

Performance

- Annual Heating Demand
  
  4.54 kBTU/ft².yr
- Annual Cooling Demand
  
  9.34 kBTU/ft².yr
- Peak Heating Load
  
  3.32 kBTU/ft².yr
- Peak Cooling Load
  
  3.09 kBTU/ft².yr
- Site Energy Use Index (EUI)
  
  16.78 kBTU/ft².yr
- Site Energy Use Index (w/Renewables)
  
  -21.64 kBTU/ft².yr
- Compliance Software
  
  WUFI Passive
- Source Energy (Residential)
  
  4445 kWh/person.yr
- Air Tightness (per enclosure area)
  
  0.036 CFM50/ft²

Enclosure

- Wall 1 R-Value
  
  34
- Wall 1 Insulation Type
  
  Mineral Wool (Cavity)
- Wall 2 Type
  
  Insulated Concrete Form (ICF)
- Wall 2 R-Value
  
  26
- Wall 2 Insulation Type
  
  EPS
- Roof 1 Type
  
  Vented Above Deck
- Roof 1 R-Value
  
  41
- Roof 1 Insulation Type
  
  Fiberglass, Other
- Roof 2 Type
  
  Vented Above Deck
- Roof 2 R-Value
  
  43
- Roof 2 Insulation Type
  
  Mineral Wool, Other
- Floor Type 1
  
  Crawlspace Floor
- Floor 1 R-Value
  
  21
- Floor 1 Insulation Type
  
  XPS
- Window Manufacturer 1
  
  APW
- Whole Window U-Value 1
  
  0.17
- Window Glazing SHGC 1
  
  0.61
- Whole Window U-Value 2
  
  0.13
- Window Glazing SHGC 2
  
  0.58
- Whole Door U-Value
  
  0.14

Systems & Equipment

- Ventilation System Manufacturer
  
  Royal Electric
- Ventilation System Layout
  
  Centralized
- Ventilation System Type
  
  ERV
- Sensible Recovery Efficiency
  
  78%
- Latent Recovery Efficiency
  
  67%
- Measured Ventilation Fan Efficiency
  
  0.76 W/cfm
- Heating System Manufacturer
  
  Mitsubishi
- Cooling System Manufacturer
  
  Mitsubishi
- Hot Water System Manufacturer
  
  Korona
- Renewable Energy Type(s)
  
  On-Site PV
- Renewable Energy Annual Production
  
  14698 kWh/yr
- Renewable Energy System Size
  
  14.17kW