CS71 Energy Code Feasibility Study in Newburyport, Massachusetts

Exterior Walls

2x6 @ 16 in. o.c. studs with R-21 mineral wool batt, plywood sheathing, self-adhered vapor-permeable air barrier, 3 in. semi-rigid mineral wool continuous insulation on thermal-isolator clips and vertical girts, siding on the girts. R-27.5 effective, 11.85 in. thick.

Below Grade Walls

N/A. The garage is unconditioned and sits outside the Phius certified enclosure per Guidebook section 1.3.1, so the below-grade walls are not a thermal boundary. Dampproofing, drainage mat and the 2 in. XPS shown on the drawings stay as a foundation-scope item.

Corridor Walls

N/A. Corridors are inside the conditioned enclosure, so the corridor walls are interior partitions, not envelope.

Slab

N/A. No conditioned space sits on grade; the lowest conditioned floor is the level above the parking garage.

Floor Over Unconditioned Space

N/A. Carried as Floor Over Podium below, which is the same surface.

Floor Over Garage

N/A. Carried as Floor Over Podium below, which is the same surface.

Floor Over Podium

R-30 closed-cell spray foam under the deck and around the beams across 26,955 sf of floor over the unconditioned garage, with an intumescent ignition barrier and the insulation returned 4 ft past the boundary of the conditioned space. This is a certified enclosure surface because Phius keeps garages outside the certification scope, so it is air sealed and inside the blower door test as well as insulated.

Rim Joists

Rim and band joists insulated and air sealed continuous with the wall assembly. On the double stud path the cavity carries through the rim rather than stopping at it, which is where most of the floor-line bridging is won or lost.

Roof

R-51 total: 4 in. tapered polyisocyanurate rated R-24 above the deck under the membrane, plus R-27 closed-cell spray foam between the trusses with an intumescent ignition barrier. Continuous vapor retarder and a protection board under the membrane.

Windows & Glass Doors

Passive-house-grade triple glazing in thermally broken multi-chamber uPVC frames, two low-E coatings, krypton or argon fill, insulated warm-edge spacers. Whole-window U-0.15 fixed and U-0.17 operable, SHGC 0.32 on solar-facing elevations and 0.20 elsewhere. Frame and glass both have to clear the ISO 13788 interior condensation check, not just the glass.

Doors

Insulated opaque exterior doors with continuous compression gasketing and thermally broken thresholds. Balcony doors U-0.20, aluminum entries U-0.25.

Air Sealing

Whole-building air sealing verified at 0.06 CFM50 per sq ft of gross enclosure, the Phius Table 1.3.3.2.0 limit for a wood-framed building of any height, plus unit compartmentalization at 0.25 CFM50 per sq ft. Continuous self-adhered air barrier from foundation to parapet, detailed at every floor line, with interim guarded blower-door rounds during construction.

HVAC

Ductless cold-climate variable-refrigerant heat pumps, one head per conditioned zone, SEER2 17 / HSPF2 10, sized to the Phius peak loads rather than to a rule of thumb. The building is fully electrified.

Ductwork

N/A. Ductless equipment, so there is no distribution duct system, no duct losses to model and no duct leakage to test.

Duct Sealing

N/A. No ductwork.

HVAC Grading

Grade I installation verification on refrigerant charge and airflow at every head.

Mechanical Ventilation

Balanced energy recovery ventilation with high apparent sensible effectiveness and a defrost strategy for climate zone 5A. Measured supply and exhaust must land within 10% of each other, or net pressurization must stay under 5 Pa. Only continuous ventilation counts toward the balance.

Local Mechanical Exhaust

Kitchen range hood and bathroom exhaust. Intermittent exhaust is assessed through the Phius Intermittent Allowance Estimator to determine whether make-up air is required.

Thermostats

Wi-Fi connected programmable thermostats, one per zone.

DHW

In-unit electric resistance water heater, 50 gallon, 240V. Simplest and lowest-cost electric option, and it keeps domestic hot water inside the unit's own energy budget. It draws more source energy than a heat pump water heater, which the Phius model has to absorb elsewhere in the envelope.

DHW Piping

Insulated hot water distribution with runs kept short and inside the thermal enclosure.

Water Fixtures

Low-flow fixtures throughout. Phius derives domestic hot water use per person, so fixture flow rates feed the source energy result directly.

Refrigerator

ENERGY STAR refrigerator, 550 kWh per year or better.

Dishwasher

ENERGY STAR dishwasher.

Clothes Washer

ENERGY STAR front-load clothes washer.

Clothes Dryer

Ventless heat pump clothes dryer. Ventless matters twice here: it removes an envelope penetration and it removes an intermittent exhaust the ventilation balance would have to answer for.

Stove / Oven

Electric range and oven. Induction is the recommended selection and carries a Mass Save adder that this study does not claim.

Lighting

100% LED with occupancy and daylight controls in common areas.

Solar Ready

Rooftop solar-ready zone reserved per 225 CMR 23 CC104 and Appendix CB. Required because both buildings are five stories or less.

EV Ready

20% of parking spaces wired EV-ready at 40 amp Level II, shared circuits with load management allowed, per C405.13 as re-required by Specialized Code CC101.5.

HPWH Ready

N/A. The building is all-electric with in-unit heat pump water heaters already installed, so there is no gas or oil water heater to pre-wire.

Paperwork & Modeling

ECC full-service Phius scope: WUFI Passive energy model to the Phius 2024 Criteria Calculator targets, design review, pre-certification and certification submissions, co-requisite program registrations, and the Phius Certified Rater or Verifier. Phius registration and certification fees are an owner-paid pass-through per Guidebook Table 1.2.0 and are excluded from this figure.

Testing & Verification

Phius QA/QC inspections, whole-building and unit air-tightness testing, and the Certified Rater field work. Inside the ECC fee, not billed separately.

Envelope

Common-area walls, roofs, floors, windows and doors are inside the certified thermal enclosure and are part of the whole-building Passive House model. Build them to the same assemblies specified for the dwelling units in this study; there is no separate common-area envelope specification.

HVAC

Heating, cooling and ventilation serving corridors, lobby, laundry, mail, amenity and stair spaces are inside the model and follow the unit specification. Ventilation must be balanced, with measured supply and exhaust within 10 percent of each other or net pressurization under 5 Pa; only continuous ventilation counts toward the balance.

DHW

Common-area service water heating is inside the model and follows the unit specification. Phius derives domestic hot water use per person, so fixture flow rates and distribution losses feed the source energy result directly.

Lighting

Interior lighting power within Table C405.3.2(2) space-by-space allowances; typical values: corridor 0.41 W/sf, lobby 0.84, laundry 0.53, stairwell 0.49, storage 0.38, enclosed office 0.74, restroom 0.63. Certified Performance suspends the prescriptive envelope and mechanical tables, not the lighting power allowance, and the installed wattage also feeds the model's source energy total.

Lighting Controls

Occupant sensor controls in offices, conference and break rooms, copy rooms, restrooms, storage rooms, locker rooms, corridors and other enclosed spaces of 300 sf or less: auto-off within 20 minutes, manual-on or auto-on to 50 percent power. Time-switch controls elsewhere; daylight-responsive controls in daylight zones.

Compliance Path

Prescriptive compliance is available for nonresidential buildings up to 20,000 sf: COMcheck envelope, lighting, and mechanical certificates plus the plan review checklist. Larger buildings comply through a performance pathway (Targeted Performance TEDI, ASHRAE 90.1 Appendix G, Passive House, or HERS for Group R).

Exterior Walls

Wall compliance is by assembly U-factor: wood-framed walls U-0.051 max, with continuous insulation derated for fasteners and linear thermal bridges per C402.7 (MA Stretch COMcheck applies the derating automatically).

Roof

Insulation entirely above deck U-0.032 (R-30 continuous; tapered systems rated 1 inch above minimum thickness). Attic assemblies U-0.021 (R-49).

Slab

Unheated slab-on-grade F-0.52 (R-15 perimeter, 24 inches below; Group R R-20); the slab insulation installation rule applies without exception.

Windows & Glass Doors

Fixed fenestration U-0.30 and operable U-0.32 (MA amendment), documented by NFRC label or simulation report; SHGC per base Table C402.4: 0.38 fixed / 0.33 operable at projection factor under 0.2.

Doors

Opaque swinging doors U-0.37; nonswinging U-0.31.

Air Sealing

Third-party air-leakage testing is mandatory: whole-building 0.35 cfm/sf at 75 Pa or better (diagnostic evaluation and sealing path between 0.35 and 0.45); continuous air barrier designed, documented, and field verified; enclosed vestibules at building entrances serving spaces of 3,000 sf or more.

HVAC

Equipment meets the C403.3.2 minimum efficiencies with the 2024 IECC heat pump tables; ventilation energy recovery per the CZ5A rows of Tables C403.7.4.2(1)-(2) (70 percent sensible at heating design).

Economizer

Air or water economizer on fan systems of 54,000 Btu/h or more (Group R 270,000 Btu/h or more) and all dedicated outdoor air systems; chilled-water triggers per Table C403.5(1).

DHW

Service water heating per base 2021 IECC C404: Table C404.2 equipment efficiencies, pipe insulation, and controls.

Lighting

Interior lighting power within Table C405.3.2(2) space-by-space allowances; typical values: corridor 0.41 W/sf, lobby 0.84, laundry 0.53, stairwell 0.49, storage 0.38, enclosed office 0.74, restroom 0.63. COMcheck documents the calculation.

Lighting Controls

Occupant sensor controls in offices, conference and break rooms, copy rooms, restrooms, storage rooms, locker rooms, corridors, and other enclosed spaces of 300 sf or less: auto-off within 20 minutes, manual-on or auto-on to 50 percent power. Time-switch controls elsewhere; daylight-responsive controls in daylight zones. MA lowers the daylight-responsive triggers: 100 W in primary sidelit and toplit zones, 300 W in sidelit zones.

Additional Efficiency Credits

Achieve 15 credits from Tables C406.1(1)-(5); MA menu highlights for CZ5A: cold-climate heat pump space heating 15 credits, heavy timber or low-GWP concrete or net-zero-GWP insulation 8 credits each, reduced air leakage at 0.20 cfm/sf tested.

Thermal Bridging

Vertical envelope performance accounts for thermal bridges: fastener derating of continuous insulation and linear bridge factors (parapets, wall-to-grade, fenestration perimeters, corners) per Table C402.7.3.1; MA Stretch COMcheck performs this automatically.

Solar Ready

Rooftop solar readiness is mandatory for new commercial buildings 5 stories or less: provide the Solar Ready Zone per IECC Appendix CB and show it on the construction documents.

EV Ready

New parking includes EV Ready spaces: 20 percent for Group R and B occupancies, 10 percent otherwise; each with a 40 A branch circuit (or shared circuit with load management) wired for 6.6 kW Level II charging terminating within 6 feet of the space.

Mixed Fuel Equipment

On the Specialized mixed-fuel pathway: combustion space heating 95 AFUE or higher; refrigerant-based cooling as heat pumps (ducted 8.1 HSPF2 / 15.2 SEER2, ductless 8.5 HSPF2 / 16 SEER2); hot water at 82 EF combustion, 2.0 UEF electric, or 0.4 solar fraction. All-electric buildings electrify 100 percent of design heating load with heat pumps.

On-Site Solar & Pre-Wiring

Specialized mixed-fuel buildings install on-site renewables at 1.5 W/sf of the three largest floors (or 75 percent of the Potential Solar Zone Area) and pre-wire all combustion equipment for future electrification: labeled 30 A 208/240 V circuit and condensate drain at water heaters, 250 V 40 A outlet at ranges, 250 V 30 A outlet at dryers.

Exterior Mineral Wool

$40.46

$3.42

$37.32

1.01

Double Stud

$40.49

$3.42

$37.35

1.01

Insulated Sheathing

$40.59

$3.42

$37.79

1.02

Exterior Walls

Double Stud

2x6 @ 16 in. o.c. load-bearing inner row, 2.5 in. clear gap, 2x4 @ 24 in. o.c. non-bearing outer row, 11.5 in. dense-pack cellulose at 3.5 lb/cu ft filling the full cavity, plywood sheathing on the outer row, vapor-permeable air barrier, siding on a rain screen. No continuous insulation. R-38.1 effective, 14.1 in. thick.

$4.38

$0.00

$4.38

0.95

Exterior Mineral Wool

2x6 @ 16 in. o.c. studs with R-21 mineral wool batt, plywood sheathing, self-adhered vapor-permeable air barrier, 3 in. semi-rigid mineral wool continuous insulation on thermal-isolator clips and vertical girts, siding on the girts. R-27.5 effective, 11.85 in. thick.

$4.35

$0.00

$4.35

0.95

Insulated Sheathing

2x6 @ 16 in. o.c. studs with R-21 mineral wool batt, 2.5 in. insulated structural sheathing rated R-12.6 acting as sheathing, WRB and continuous insulation in one panel, taped seams, siding on furring. R-28.1 effective, 10.0 in. thick.

$3.51

$0.00

$3.51

0.95

Below Grade Walls

Double Stud

N/A. The garage is unconditioned and sits outside the Phius certified enclosure per Guidebook section 1.3.1, so the below-grade walls are not a thermal boundary. Dampproofing, drainage mat and the 2 in. XPS shown on the drawings stay as a foundation-scope item.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. The garage is unconditioned and sits outside the Phius certified enclosure per Guidebook section 1.3.1, so the below-grade walls are not a thermal boundary. Dampproofing, drainage mat and the 2 in. XPS shown on the drawings stay as a foundation-scope item.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. The garage is unconditioned and sits outside the Phius certified enclosure per Guidebook section 1.3.1, so the below-grade walls are not a thermal boundary. Dampproofing, drainage mat and the 2 in. XPS shown on the drawings stay as a foundation-scope item.

$0.00

$0.00

$0.00

1.00

Corridor Walls

Double Stud

N/A. Corridors are inside the conditioned enclosure, so the corridor walls are interior partitions, not envelope.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. Corridors are inside the conditioned enclosure, so the corridor walls are interior partitions, not envelope.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. Corridors are inside the conditioned enclosure, so the corridor walls are interior partitions, not envelope.

$0.00

$0.00

$0.00

1.00

Slab

Double Stud

N/A. No conditioned space sits on grade; the lowest conditioned floor is the level above the parking garage.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. No conditioned space sits on grade; the lowest conditioned floor is the level above the parking garage.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. No conditioned space sits on grade; the lowest conditioned floor is the level above the parking garage.

$0.00

$0.00

$0.00

1.00

Floor Over Unconditioned Space

Double Stud

N/A. Carried as Floor Over Podium below, which is the same surface.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. Carried as Floor Over Podium below, which is the same surface.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. Carried as Floor Over Podium below, which is the same surface.

$0.00

$0.00

$0.00

1.00

Floor Over Garage

Double Stud

N/A. Carried as Floor Over Podium below, which is the same surface.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. Carried as Floor Over Podium below, which is the same surface.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. Carried as Floor Over Podium below, which is the same surface.

$0.00

$0.00

$0.00

1.00

Floor Over Podium

Double Stud

R-30 closed-cell spray foam under the deck and around the beams across 26,955 sf of floor over the unconditioned garage, with an intumescent ignition barrier and the insulation returned 4 ft past the boundary of the conditioned space. This is a certified enclosure surface because Phius keeps garages outside the certification scope, so it is air sealed and inside the blower door test as well as insulated.

$1.15

$0.00

$1.15

0.90

Exterior Mineral Wool

R-30 closed-cell spray foam under the deck and around the beams across 26,955 sf of floor over the unconditioned garage, with an intumescent ignition barrier and the insulation returned 4 ft past the boundary of the conditioned space. This is a certified enclosure surface because Phius keeps garages outside the certification scope, so it is air sealed and inside the blower door test as well as insulated.

$1.15

$0.00

$1.15

0.90

Insulated Sheathing

R-30 closed-cell spray foam under the deck and around the beams across 26,955 sf of floor over the unconditioned garage, with an intumescent ignition barrier and the insulation returned 4 ft past the boundary of the conditioned space. This is a certified enclosure surface because Phius keeps garages outside the certification scope, so it is air sealed and inside the blower door test as well as insulated.

$1.15

$0.00

$1.15

0.90

Rim Joists

Double Stud

Rim and band joists insulated and air sealed continuous with the wall assembly. On the double stud path the cavity carries through the rim rather than stopping at it, which is where most of the floor-line bridging is won or lost.

$0.20

$0.00

$0.20

0.95

Exterior Mineral Wool

Rim and band joists insulated and air sealed continuous with the wall assembly. On the double stud path the cavity carries through the rim rather than stopping at it, which is where most of the floor-line bridging is won or lost.

$0.20

$0.00

$0.20

0.95

Insulated Sheathing

Rim and band joists insulated and air sealed continuous with the wall assembly. On the double stud path the cavity carries through the rim rather than stopping at it, which is where most of the floor-line bridging is won or lost.

$0.20

$0.00

$0.20

0.95

Roof

Double Stud

R-51 total: 4 in. tapered polyisocyanurate rated R-24 above the deck under the membrane, plus R-27 closed-cell spray foam between the trusses with an intumescent ignition barrier. Continuous vapor retarder and a protection board under the membrane.

$1.46

$0.00

$1.46

1.05

Exterior Mineral Wool

R-51 total: 4 in. tapered polyisocyanurate rated R-24 above the deck under the membrane, plus R-27 closed-cell spray foam between the trusses with an intumescent ignition barrier. Continuous vapor retarder and a protection board under the membrane.

$1.46

$0.00

$1.46

1.05

Insulated Sheathing

R-51 total: 4 in. tapered polyisocyanurate rated R-24 above the deck under the membrane, plus R-27 closed-cell spray foam between the trusses with an intumescent ignition barrier. Continuous vapor retarder and a protection board under the membrane.

$1.46

$0.00

$1.46

1.05

Windows & Glass Doors

Double Stud

Passive-house-grade triple glazing in thermally broken multi-chamber uPVC frames, two low-E coatings, krypton or argon fill, insulated warm-edge spacers. Whole-window U-0.15 fixed and U-0.17 operable, SHGC 0.32 on solar-facing elevations and 0.20 elsewhere. Frame and glass both have to clear the ISO 13788 interior condensation check, not just the glass.

$3.82

$0.00

$3.82

1.00

Exterior Mineral Wool

Passive-house-grade triple glazing in thermally broken multi-chamber uPVC frames, two low-E coatings, krypton or argon fill, insulated warm-edge spacers. Whole-window U-0.15 fixed and U-0.17 operable, SHGC 0.32 on solar-facing elevations and 0.20 elsewhere. Frame and glass both have to clear the ISO 13788 interior condensation check, not just the glass.

$3.82

$0.00

$3.82

1.00

Insulated Sheathing

Passive-house-grade triple glazing in thermally broken multi-chamber uPVC frames, two low-E coatings, krypton or argon fill, insulated warm-edge spacers. Whole-window U-0.15 fixed and U-0.17 operable, SHGC 0.32 on solar-facing elevations and 0.20 elsewhere. Frame and glass both have to clear the ISO 13788 interior condensation check, not just the glass.

$3.82

$0.00

$3.82

1.00

Doors

Double Stud

Insulated opaque exterior doors with continuous compression gasketing and thermally broken thresholds. Balcony doors U-0.20, aluminum entries U-0.25.

$0.35

$0.00

$0.35

0.95

Exterior Mineral Wool

Insulated opaque exterior doors with continuous compression gasketing and thermally broken thresholds. Balcony doors U-0.20, aluminum entries U-0.25.

$0.35

$0.00

$0.35

0.95

Insulated Sheathing

Insulated opaque exterior doors with continuous compression gasketing and thermally broken thresholds. Balcony doors U-0.20, aluminum entries U-0.25.

$0.35

$0.00

$0.35

0.95

Air Sealing

Double Stud

Whole-building air sealing verified at 0.06 CFM50 per sq ft of gross enclosure, the Phius Table 1.3.3.2.0 limit for a wood-framed building of any height, plus unit compartmentalization at 0.25 CFM50 per sq ft. Continuous self-adhered air barrier from foundation to parapet, detailed at every floor line, with interim guarded blower-door rounds during construction.

$2.40

$0.00

$2.40

0.95

Exterior Mineral Wool

Whole-building air sealing verified at 0.06 CFM50 per sq ft of gross enclosure, the Phius Table 1.3.3.2.0 limit for a wood-framed building of any height, plus unit compartmentalization at 0.25 CFM50 per sq ft. Continuous self-adhered air barrier from foundation to parapet, detailed at every floor line, with interim guarded blower-door rounds during construction.

$2.40

$0.00

$2.40

0.95

Insulated Sheathing

Whole-building air sealing verified at 0.06 CFM50 per sq ft of gross enclosure, the Phius Table 1.3.3.2.0 limit for a wood-framed building of any height, plus unit compartmentalization at 0.25 CFM50 per sq ft. Continuous self-adhered air barrier from foundation to parapet, detailed at every floor line, with interim guarded blower-door rounds during construction.

$2.40

$0.00

$2.40

0.95

HVAC

Double Stud

Ductless cold-climate variable-refrigerant heat pumps, one head per conditioned zone, SEER2 17 / HSPF2 10, sized to the Phius peak loads rather than to a rule of thumb. The building is fully electrified.

$9.83

$0.00

$9.83

1.15

Exterior Mineral Wool

Ductless cold-climate variable-refrigerant heat pumps, one head per conditioned zone, SEER2 17 / HSPF2 10, sized to the Phius peak loads rather than to a rule of thumb. The building is fully electrified.

$9.83

$0.00

$9.83

1.15

Insulated Sheathing

Ductless cold-climate variable-refrigerant heat pumps, one head per conditioned zone, SEER2 17 / HSPF2 10, sized to the Phius peak loads rather than to a rule of thumb. The building is fully electrified.

$9.83

$0.00

$9.83

1.15

Ductwork

Double Stud

N/A. Ductless equipment, so there is no distribution duct system, no duct losses to model and no duct leakage to test.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. Ductless equipment, so there is no distribution duct system, no duct losses to model and no duct leakage to test.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. Ductless equipment, so there is no distribution duct system, no duct losses to model and no duct leakage to test.

$0.00

$0.00

$0.00

1.00

Duct Sealing

Double Stud

N/A. No ductwork.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. No ductwork.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. No ductwork.

$0.00

$0.00

$0.00

1.00

HVAC Grading

Double Stud

Grade I installation verification on refrigerant charge and airflow at every head.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

Grade I installation verification on refrigerant charge and airflow at every head.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

Grade I installation verification on refrigerant charge and airflow at every head.

$0.00

$0.00

$0.00

1.00

Mechanical Ventilation

Double Stud

Balanced energy recovery ventilation with high apparent sensible effectiveness and a defrost strategy for climate zone 5A. Measured supply and exhaust must land within 10% of each other, or net pressurization must stay under 5 Pa. Only continuous ventilation counts toward the balance.

$2.12

$0.00

$2.12

1.20

Exterior Mineral Wool

Balanced energy recovery ventilation with high apparent sensible effectiveness and a defrost strategy for climate zone 5A. Measured supply and exhaust must land within 10% of each other, or net pressurization must stay under 5 Pa. Only continuous ventilation counts toward the balance.

$2.12

$0.00

$2.12

1.20

Insulated Sheathing

Balanced energy recovery ventilation with high apparent sensible effectiveness and a defrost strategy for climate zone 5A. Measured supply and exhaust must land within 10% of each other, or net pressurization must stay under 5 Pa. Only continuous ventilation counts toward the balance.

$2.12

$0.00

$2.12

1.20

Local Mechanical Exhaust

Double Stud

Kitchen range hood and bathroom exhaust. Intermittent exhaust is assessed through the Phius Intermittent Allowance Estimator to determine whether make-up air is required.

$0.98

$0.00

$0.98

1.05

Exterior Mineral Wool

Kitchen range hood and bathroom exhaust. Intermittent exhaust is assessed through the Phius Intermittent Allowance Estimator to determine whether make-up air is required.

$0.98

$0.00

$0.98

1.05

Insulated Sheathing

Kitchen range hood and bathroom exhaust. Intermittent exhaust is assessed through the Phius Intermittent Allowance Estimator to determine whether make-up air is required.

$0.98

$0.00

$0.98

1.05

Thermostats

Double Stud

Wi-Fi connected programmable thermostats, one per zone.

$0.11

$0.00

$0.11

1.05

Exterior Mineral Wool

Wi-Fi connected programmable thermostats, one per zone.

$0.11

$0.00

$0.11

1.05

Insulated Sheathing

Wi-Fi connected programmable thermostats, one per zone.

$0.11

$0.00

$0.11

1.05

DHW

Double Stud

In-unit electric resistance water heater, 50 gallon, 240V. Simplest and lowest-cost electric option, and it keeps domestic hot water inside the unit's own energy budget. It draws more source energy than a heat pump water heater, which the Phius model has to absorb elsewhere in the envelope.

$0.86

$0.00

$0.86

0.90

Exterior Mineral Wool

In-unit electric resistance water heater, 50 gallon, 240V. Simplest and lowest-cost electric option, and it keeps domestic hot water inside the unit's own energy budget. It draws more source energy than a heat pump water heater, which the Phius model has to absorb elsewhere in the envelope.

$0.86

$0.00

$0.86

0.90

Insulated Sheathing

In-unit integrated heat pump water heater, 45 or 50 gallon, 240V. Keeps domestic hot water electric and inside the unit's own energy budget.

$1.83

$0.00

$1.83

1.20

DHW Piping

Double Stud

Insulated hot water distribution with runs kept short and inside the thermal enclosure.

$0.69

$0.00

$0.69

0.95

Exterior Mineral Wool

Insulated hot water distribution with runs kept short and inside the thermal enclosure.

$0.69

$0.00

$0.69

0.95

Insulated Sheathing

Insulated hot water distribution with runs kept short and inside the thermal enclosure.

$0.69

$0.00

$0.69

0.95

Water Fixtures

Double Stud

Low-flow fixtures throughout. Phius derives domestic hot water use per person, so fixture flow rates feed the source energy result directly.

$1.72

$0.00

$1.72

1.00

Exterior Mineral Wool

Low-flow fixtures throughout. Phius derives domestic hot water use per person, so fixture flow rates feed the source energy result directly.

$1.72

$0.00

$1.72

1.00

Insulated Sheathing

Low-flow fixtures throughout. Phius derives domestic hot water use per person, so fixture flow rates feed the source energy result directly.

$1.72

$0.00

$1.72

1.00

Refrigerator

Double Stud

ENERGY STAR refrigerator, 550 kWh per year or better.

$0.75

$0.00

$0.75

1.10

Exterior Mineral Wool

ENERGY STAR refrigerator, 550 kWh per year or better.

$0.75

$0.00

$0.75

1.10

Insulated Sheathing

ENERGY STAR refrigerator, 550 kWh per year or better.

$0.75

$0.00

$0.75

1.10

Dishwasher

Double Stud

ENERGY STAR dishwasher.

$0.40

$0.00

$0.40

1.10

Exterior Mineral Wool

ENERGY STAR dishwasher.

$0.40

$0.00

$0.40

1.10

Insulated Sheathing

ENERGY STAR dishwasher.

$0.40

$0.00

$0.40

1.10

Clothes Washer

Double Stud

ENERGY STAR front-load clothes washer.

$0.57

$0.00

$0.57

1.10

Exterior Mineral Wool

ENERGY STAR front-load clothes washer.

$0.57

$0.00

$0.57

1.10

Insulated Sheathing

ENERGY STAR front-load clothes washer.

$0.57

$0.00

$0.57

1.10

Clothes Dryer

Double Stud

Ventless heat pump clothes dryer. Ventless matters twice here: it removes an envelope penetration and it removes an intermittent exhaust the ventilation balance would have to answer for.

$0.52

$0.00

$0.52

1.00

Exterior Mineral Wool

Ventless heat pump clothes dryer. Ventless matters twice here: it removes an envelope penetration and it removes an intermittent exhaust the ventilation balance would have to answer for.

$0.52

$0.00

$0.52

1.00

Insulated Sheathing

Ventless heat pump clothes dryer. Ventless matters twice here: it removes an envelope penetration and it removes an intermittent exhaust the ventilation balance would have to answer for.

$0.52

$0.00

$0.52

1.00

Stove / Oven

Double Stud

Electric range and oven. Induction is the recommended selection and carries a Mass Save adder that this study does not claim.

$0.75

$0.00

$0.75

1.05

Exterior Mineral Wool

Electric range and oven. Induction is the recommended selection and carries a Mass Save adder that this study does not claim.

$0.75

$0.00

$0.75

1.05

Insulated Sheathing

Electric range and oven. Induction is the recommended selection and carries a Mass Save adder that this study does not claim.

$0.75

$0.00

$0.75

1.05

Lighting

Double Stud

100% LED with occupancy and daylight controls in common areas.

$4.00

$0.00

$4.00

0.85

Exterior Mineral Wool

100% LED with occupancy and daylight controls in common areas.

$4.00

$0.00

$4.00

0.85

Insulated Sheathing

100% LED with occupancy and daylight controls in common areas.

$4.00

$0.00

$4.00

0.85

Solar Ready

Double Stud

Rooftop solar-ready zone reserved per 225 CMR 23 CC104 and Appendix CB. Required because both buildings are five stories or less.

$0.30

$0.00

$0.30

1.00

Exterior Mineral Wool

Rooftop solar-ready zone reserved per 225 CMR 23 CC104 and Appendix CB. Required because both buildings are five stories or less.

$0.30

$0.00

$0.30

1.00

Insulated Sheathing

Rooftop solar-ready zone reserved per 225 CMR 23 CC104 and Appendix CB. Required because both buildings are five stories or less.

$0.30

$0.00

$0.30

1.00

EV Ready

Double Stud

20% of parking spaces wired EV-ready at 40 amp Level II, shared circuits with load management allowed, per C405.13 as re-required by Specialized Code CC101.5.

$0.63

$0.00

$0.63

1.00

Exterior Mineral Wool

20% of parking spaces wired EV-ready at 40 amp Level II, shared circuits with load management allowed, per C405.13 as re-required by Specialized Code CC101.5.

$0.63

$0.00

$0.63

1.00

Insulated Sheathing

20% of parking spaces wired EV-ready at 40 amp Level II, shared circuits with load management allowed, per C405.13 as re-required by Specialized Code CC101.5.

$0.63

$0.00

$0.63

1.00

HPWH Ready

Double Stud

N/A. The building is all-electric with in-unit heat pump water heaters already installed, so there is no gas or oil water heater to pre-wire.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

N/A. The building is all-electric with in-unit heat pump water heaters already installed, so there is no gas or oil water heater to pre-wire.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

N/A. The building is all-electric with in-unit heat pump water heaters already installed, so there is no gas or oil water heater to pre-wire.

$0.00

$0.00

$0.00

1.00

Paperwork & Modeling

Double Stud

ECC full-service Phius scope: WUFI Passive energy model to the Phius 2024 Criteria Calculator targets, design review, pre-certification and certification submissions, co-requisite program registrations, and the Phius Certified Rater or Verifier. Phius registration and certification fees are an owner-paid pass-through per Guidebook Table 1.2.0 and are excluded from this figure.

$2.50

$3.42

$-0.92

1.00

Exterior Mineral Wool

ECC full-service Phius scope: WUFI Passive energy model to the Phius 2024 Criteria Calculator targets, design review, pre-certification and certification submissions, co-requisite program registrations, and the Phius Certified Rater or Verifier. Phius registration and certification fees are an owner-paid pass-through per Guidebook Table 1.2.0 and are excluded from this figure.

$2.50

$3.42

$-0.92

1.00

Insulated Sheathing

ECC full-service Phius scope: WUFI Passive energy model to the Phius 2024 Criteria Calculator targets, design review, pre-certification and certification submissions, co-requisite program registrations, and the Phius Certified Rater or Verifier. Phius registration and certification fees are an owner-paid pass-through per Guidebook Table 1.2.0 and are excluded from this figure.

$2.50

$3.42

$-0.92

1.00

Testing & Verification

Double Stud

Phius QA/QC inspections, whole-building and unit air-tightness testing, and the Certified Rater field work. Inside the ECC fee, not billed separately.

$0.00

$0.00

$0.00

1.00

Exterior Mineral Wool

Phius QA/QC inspections, whole-building and unit air-tightness testing, and the Certified Rater field work. Inside the ECC fee, not billed separately.

$0.00

$0.00

$0.00

1.00

Insulated Sheathing

Phius QA/QC inspections, whole-building and unit air-tightness testing, and the Certified Rater field work. Inside the ECC fee, not billed separately.

$0.00

$0.00

$0.00

1.00