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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
- Jan. Webinar: Walking Through METr
  January 13
- Phius Certified Consultant Training & Certification Exam | January 2026
  January 20 – 30
- Member Office Hours - METr
  January 20
- Phius Certified Builder Training and Certification Exam | January 2026
  January 20 – 30
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Project 1945

555 Merrimack St.; Lowell, MA

ICON Architecture

Lowell, Massachusetts

Building Function

Multifamily
Project Type

New Construction
ASHRAE Climate Zone

5A - Cool - Humid
Construction Completion

2022
Status

Certified
INT. Conditioned Floor Area

25283 ft²

Core Project Team

Phius CPHB

Nat Coughlin
Phius CPHB

Julie Sirois
Phius Certified Verifier

Nathan Wicksman
Phius CPHC (Secondary)

Gabrielle Aitcheson
Phius CPHC (Lead)

Sarah Carter
Project Submitter

Daniel Perez

Project Information

- Architecture Planning
  
  ICON Architecture
- Building Owner
  
  Coalition For A Better Acre
- Mechanical Systems Designer
  
  Petersen Engineering
- Construction Company
  
  L. D. Russo
- Building Function
  
  Multifamily
- Project Type
  
  New Construction
- Construction Type
  
  Wood Frame
- Number of Units
  
  27
- Number of Stories
  
  4
- Program Version
  
  Phius CORE 2021
- INT. Conditioned Floor Area
  
  25283 ft²
- Market Category
  
  Affordable Housing
- Status
  
  Certified
- Design Certification
  
  July 21, 2022
- Final Certification
  
  July 15, 2025
- Construction Completion
  
  2022
- ASHRAE Climate Zone
  
  5A - Cool - Humid
- Region
  
  Northeast

Performance

- Annual Heating Demand
  
  3.99 kBTU/ft².yr
- Annual Cooling Demand
  
  2.55 kBTU/ft².yr
- Peak Heating Load
  
  4.17 kBTU/ft².yr
- Peak Cooling Load
  
  1.82 kBTU/ft².yr
- Site Energy Use Index (EUI)
  
  20.61 kBTU/ft².yr
- Site Energy Use Index (w/Renewables)
  
  17.59 kBTU/ft².yr
- Compliance Software
  
  WUFI Passive
- Source Energy (Residential)
  
  3891 kWh/person.yr
- Source Energy (Residential w/Renewables)
  
  3214 kWh/person.yr
- Air Tightness (per enclosure area)
  
  0.054 CFM50/ft²

Enclosure

- Wall 1 R-Value
  
  29
- Roof 1 R-Value
  
  50
- Floor 1 R-Value
  
  11
- Window Manufacturer 1
  
  Aspekt
- Whole Window U-Value 1
  
  0.19
- Window Glazing SHGC 1
  
  0.29
- Window Manufacturer 2
  
  Alpen

Systems & Equipment

- Ventilation System Manufacturer
  
  Annexair & Zehnder
- Ventilation System Layout
  
  Centralized
- Ventilation System Type
  
  ERV
- Sensible Recovery Efficiency
  
  82%
- Measured Ventilation Fan Efficiency
  
  0.75 W/cfm
- Heating System Manufacturer
  
  Mitsubishi
- Heating System Type
  
  Variable Refrigerant Flow (VRF)
- Cooling System Manufacturer
  
  Mitsubishi
- Hot Water System Manufacturer
  
  Lochinvar
- Hot Water System Layout
  
  Centralized
- Hot Water System Type
  
  Natural Gas Water Heater
- Renewable Energy Type(s)
  
  On-Site PV
- Renewable Energy Annual Production
  
  27417 kWh/yr
- Renewable Energy System Size
  
  23.04kW