Crescent Crossings 1C by Viking Construction

The third phase of Crescent Crossings was engineered and constructed to offset carbon emissions. The $31 million redevelopment project created 86 energy-efficient apartment units to serve a mixed-income community in the urban setting of Bridgeport, CT. The building itself was constructed and designed to conserve energy, produce energy, and encourage energy efficiencies.

PHIUS and LEED certifications are pending while the ZERH, IAP, and ESMFNC certifications are in-hand. The tight thermal envelope is achieved with R15 continuous insulation over Blueskin membrane and R21 cavity insulation, R30 on the roof deck and R30 in trusses, and triple-pane windows. The construction team focused on an airtight exterior envelope as well as compartmentalization with the following results:

• whole building infiltration rate (average of pressurized and depressurized) tested 7,899 cfm75 which is less than the 8,408 cfm75 target
• units ranged from 0.14 – 0.22 cfm50/sf enclosure which is significantly less than the .30 target

Spaces are heated and cooled by high efficiency Mitsubishi heat pumps (9.2 HSPF2, 18.7 SEER2), hot water supplied by Navien tankless appliances in each apartment (natural gas infrastructure was installed several years ago), and ventilation supplied with central Swegon ERV’s. CAR dampers are installed at each supply and return, which facilitated precise balancing.

HERS Indexes range from 39 – 42 with an annual energy savings prediction of $2,000 per unit which is less than half the reference home but includes the utilities monthly distribution and delivery fees.

A 62kW photovoltaic rooftop system is anticipated to offset interior and exterior common and amenity usage plus all the ventilation systems’ energy use.

Viking Construction followed best practices by recycling materials pulled from the site (stone, concrete etc.), left-over scrap construction materials (wood, metals, plastics), as well as all packaging. Additionally, Viking reduced the use of construction vehicles on the site to minimize fuel consumption as much as possible.

The building was constructed with specific attention to low emitting finishes and substituting plastic-based insulation with therma fiber products wherever possible. There is no carpet in the building and ducted systems were diligently covered to keep out construction debris.

Ownership is anxious to compare energy and water savings, resident comfort, and enhanced durability against the two previous phases. Crescent Crossings 1A, completed in 2017 and 1B, completed in 2018 were built to earlier versions of ENERGY STAR and LEED without the added rigor of ZERH and PHIUS that CC1C achieved.