Project
Old Colony Phase Six
Residential: Affordable Multi Family
South Boston, MA | 2026
- 115K GSF
About
Old Colony Phase Six delivers 89 affordable apartments across five stories as
part of the ongoing Old Colony redevelopment in Boston. The all-electric
building uses Mitsubishi VRF for heating and cooling, a centralized split heat
pump water heater, and semi-centralized ERVs recovering 79% of sensible heat.
A 92 kW rooftop solar array generates roughly 113,000 kWh per year, and
measured airtightness came in at 0.039 CFM50/sf.
Is the project Net Zero Energy or Net Zero Energy Ready?
Net Zero Ready
Project Size in GSF
115K
Category of height
Mid-Rise
Number of residential units
89
How is the building all-electric for heating?
Variable Refrigerant Flow (VRF)
Is the service hot water all-electric?
Yes
What is the primary system type for domestic hot water?
Ground-source heat pump
On-site renewable energy
22%
Is the owner purchasing off-site renewable energy to offset all electricity consumption?
Unknown
Certifications related to Energy / Carbon
PHIUS
Site EUI Energy Use Intensity is the amount of energy a project uses per square foot over the course of a year. Site EUI = Annual Energy Use (kBtus) / Building(s) Area (ft²) / One Year (yr)
15.5 kBtu/sf/year
Net Site EUI
12.2 kBtu/sf/year
The EUI is
Modeled
Carbon Emissions Intensity (CEI)
0.63kg/CO2e/sf
What is the climate zone for this project?
5A Cool Humid