CS66 Energy Code Feasibility Study in Lowell, Massachusetts
Energy code feasibility study for a 205-unit Multifamily in Massachusetts. Compares multiple design paths. Recommended: NO CI (All-Electric). View full study.
- Study Type
- Energy Code Feasibility Study
- State
- Massachusetts
- Units
- 205
- Building Type
- Multifamily
- Fuel Type
- All-Electric
- Recommended Path
- NO CI (All-Electric)
Goal
To find the most cost-effective compliance path, this report isolates energy code related costs from total construction. We use real bid data from vendors & clients to create a reliable framework for aligning incentives and design, with all recommendations confirmed by detailed energy modeling.
Project
- Lowell, MA
- 1 Building | 205 Units | 192,505 SF Conditioned
- New Construction | Multifamily High-Rise | 6 stories over podium, 205 units
- All-Electric | Stretch Code | HERS ≤ 45 | ESTAR MFNC v1.2
Overview
Read This: This report compares different ways you can build the project and meet energy code, looking at both cost and incentives, with the ultimate goal as finding the most affordable path.
- The overview outlines the key differences between each of the paths we show in this report and why we recommend the one we picked over the others.
- The recommended design section is where we share the requirements and incentives for the path we think is best based on affordability.
- The path comparison section shows the detailed requirements and incentives for each path we compared, basically showing our work if you want to dig in.
Path Summaries
All three paths meet the Massachusetts energy code and are modeled to pass on a lean margin, and all three are fully electric, so the choice between them comes down to cost and how easily each one builds rather than compliance.
NO CI (All-Electric): Recommended
This is the recommended path at approximately $34.05/sf net. It is the priciest of the three, but only by about $0.76/sf over the cheapest option, and in exchange it drops an exterior insulation layer that the model shows buys essentially nothing here, making it the fastest and most foolproof of the three to build. It stays fully electric with full incentive eligibility, so a small first-cost premium buys a simpler, quicker build.
NO HPWH (All-Electric): Alternative
At approximately $33.57/sf net, this path lands about $0.48/sf under the recommended path and shares its builder-friendly envelope while using the simplest in-unit water heating of the three. It stays fully electric, but it earns modestly lower incentives and takes a less future-ready approach to hot water. Choose it when shaving first cost with the simplest possible mechanicals matters more than maximizing incentives and long-term flexibility.
CI (All-Electric): Not Recommended
This is the cheapest path at approximately $33.29/sf net, but it saves only about $0.76/sf over the recommended path while being the slowest and most labor-intensive of the three to build. The entire saving comes from an exterior insulation layer that the model shows delivers essentially no benefit here, and it adds an extra trade, more detailing, and schedule drag to install. The only reason to choose it is if capturing that last fraction of a dollar per square foot outweighs a faster, simpler build.
Path Cost Comparison
Code Path
Permit / Certificate of Occupancy Requirements
High Rise Buildings
Recommended Design
This section outlines the design requirements, product recommendations, and incentives for the design that we believe will be the most affordable path to meeting energy code.
Recommended Design - Incentives
Incentives Available: $410,000
- MassSave Multifamily High Rise Program Energy Star Tier ($358,750) (Program Breakdown): You get this rebate for having your building(s) certified for the Energy Star MFNC v1.2 program. This requires pre-approval via an application to be submitted before construction starts. This rebate comes in the form of a check within 4 months of certification documentation being provided to MassSave, typically this is 4 months after construction is complete.
- In-Unit Heat Pump Water Heater Adder ($51,250) : A MassSave market transformation adder of $250 per unit for installing a heat-pump water heater in each dwelling unit. This rebate comes in the form of a check within 4 months of certification documentation being provided to MassSave, typically this is 4 months after construction is complete.
Recommended Design - Units
Item | Detailed Specifications |
|---|---|
Exterior Walls | R-38 closed-cell spray foam in a 2x6 @ 16" o.c. cavity, no continuous insulation. |
Below Grade Walls | N/A |
Corridor Walls | N/A |
Slab | R-10 continuous under-slab insulation; fully insulated. |
Floor Over Unconditioned Space | N/A |
Floor Over Garage | N/A |
Floor Over Podium | R-30 continuous insulation. |
Rim Joists | R-38 rim/band insulation at floor transitions. |
Roof | Sealed attic: R-19 cavity insulation + R-30 continuous insulation (roof deck). |
Windows & Glass Doors | High performance triple-pane windows, U-0.18 / SHGC 0.18. |
Doors | Opaque: insulated steel, U-0.21 (R-4.75). |
Air Sealing | ≤ 0.27 CFM50 per sqft of enclosure (compartmentalization); tested. |
HVAC | Ductless heat pump (PTHP), through-wall (as modeled); SEER2 13.5; HSPF2 6.8. |
Ductwork | N/A |
Duct Sealing | N/A |
HVAC Grading | Fan Flow Test: N/A Watt Draw Test: N/A Refrigerant Charge: N/A |
Mechanical Ventilation | In-unit ERV; 30-60 CFM by unit size (studio 30 / 1BR 40 / 2BR 60); ≥ 87% recovery efficiency (Panasonic Intelli-Balance). |
Local Mechanical Exhaust | Bathroom(s): ≥ 50 CFM intermittent & ≤ 3.0 sones OR ≥ 20 CFM continuous & ≤ 2.0 sones. Kitchen(s): ≥ 100 CFM intermittent & ≤ 3.0 sones OR continuous, ≥ 5 ACH. Both: Exhaust directly outdoors, ENERGY STAR certified. |
Thermostats | Programmable thermostat (as modeled). |
DHW | Integrated heat pump water heater (HPWH) (as modeled); UEF 3.88; 45 gal; in the conditioned corridor; 240V. |
DHW Piping | Supply piping insulated to R-3 minimum. |
Water Fixtures | WaterSense certified (Lavatory ≤1.2 GPM; Shower ≤2.0 GPM; Kitchen ≤2.2 GPM). |
Refrigerator | ≤ 450 kWh/yr (studio & 1BR) / ≤ 550 kWh/yr (2BR); ENERGY STAR; electric. |
Dishwasher | ≤ 269 kWh/yr; ENERGY STAR; electric. |
Clothes Washer | IMEF 2.06; ENERGY STAR; electric. |
Clothes Dryer | Heat pump electric dryer, ventless; ENERGY STAR. |
Stove / Oven | Electric induction cooktop; convection oven. |
Lighting | 100% high-efficacy (LED). |
Solar Ready | N/A |
EV Ready | At least 20% of parking spaces wired EV-ready (40-amp Level II; shared circuits with load management allowed). |
HPWH Ready | N/A |
Paperwork & Modeling | ENERGY STAR energy model to the target (per-unit HERS or whole-building ASHRAE path), the ENERGY STAR design-review checklist and multifamily workbook, and an HVAC design report. |
Testing & Verification | ENERGY STAR field verification: pre-drywall and final inspections, unit air-tightness (blower door), and ventilation and exhaust airflow testing. |
Recommended Design - Common Areas & Clubhouse
Item | Common Areas (Residential Bldgs) | Clubhouse |
|---|---|---|
Exterior Walls | Wood-frame: R-13 + R-7.5 CI or R-20 + R-3.8 CI or R-30. Steel-frame: R-13 + R-7.5 CI (CI mandatory). | Same |
Below Grade Walls | R-7.5 continuous insulation. | Same |
Corridor Walls | Common area wall insulation governs; refer to Exterior Walls. | Same as clubhouse wall insulation. |
Slab | R-10 edge, extending 4 feet or 24 inches below grade (whichever is greater). | Same |
Floor Over Unconditioned Space | R-13 cavity with R-17 CI, or R-30 cavity only, or R-19 cavity with R-5 CI. | U-factor ≤ 0.033 per commercial assembly (R-13/R-17 equivalent). |
Floor Over Garage | R-13 cavity with R-17 CI, or R-30 cavity only, or R-19 cavity with R-5 CI. | U-factor ≤ 0.033 per commercial assembly (R-13/R-17 equivalent). |
Floor Over Podium | R-30 continuous insulation. | Same |
Rim Joists | Insulation and air barrier continuous through rim joint; seal with caulk or foam; match wall R-value above and below grade. | Same, continuous with wall assembly. |
Roof | R-30 continuous insulation at deck; or R-49 in attic with air barrier and Grade I insulation installation. | Same |
Windows & Glass Doors | Fixed U ≤ 0.30; operable U ≤ 0.30; SHGC ≤ 0.40. | Fixed U ≤ 0.30; operable U ≤ 0.32; SHGC ≤ 0.40. |
Doors | Glazed entrance U ≤ 0.60; opaque U ≤ 0.37. | Glazed entrance U ≤ 0.77; opaque U ≤ 0.37. |
Air Sealing | Continuous air barrier per residential air-barrier table; Grade I insulation install; penetrations, rough openings, and electrical boxes sealed; unit-to-corridor doors gasketed. Enclosed common spaces ≤ 1,500 sqft verified by inspection. | Continuous air barrier; whole-building blower door ≤ 0.35 CFM/sqft at 75 Pa. |
HVAC | Ducted split HP: SEER2 15.2 / HSPF2 7.8. Ductless: 16 / 8.2. Packaged: 15.2 / 7.7. PTAC/PTHP/room AC certified to ENERGY STAR. Manual J/S sizing. | Same, plus cold-climate HP (COP ≥ 1.75 at 5°F, no resistance except defrost); each cooling system ≤ 54 kBtu/h exemption, or add economizer. |
Ductwork | Distribute conditioned air to all occupied common spaces. Ducts and air-handler units located entirely within conditioned space. Design and test to standard duct-design and duct-leakage practice. | Distribute conditioned air to all spaces. Ducts and air-handler units located in conditioned space. Design and testing per commercial code standards. |
Duct Sealing | Per system, final test (at 25 Pa): 6 CFM per 100 sqft or 60 CFM (no return ducts); 8 CFM per 100 sqft or 80 CFM (1–2 return ducts); 12 CFM per 100 sqft or 120 CFM (3+ returns). Rough-in: 3/30, 4/40, or 6/60. All ducts and AHU in conditioned space. Tested. | Same final and rough-in targets. All ducts in conditioned space. |
HVAC Grading | N/A | Same |
Mechanical Ventilation | Outdoor air to all occupied common spaces: Lobby/Office 5 cfm/person + 0.06 cfm/sqft; Fitness 20 + 0.06; Corridor 0.06; Laundry 5 + 0.12. Installed at design airflow or above. Mandatory DCV for spaces over 500 sqft and over 25 people/1,000 sqft. Energy recovery (ERV, 70% sensible / 60% enthalpy) required for qualifying systems by runtime and outdoor-air fraction. | Same ventilation rates. Plus: demand control ventilation for spaces over 500 sqft with occupancy over 25 people/1,000 sqft. Energy recovery (ERV) required if: any system operates 8,000+ hrs/year with ≥ 10% outdoor air; or shorter-runtime systems above 10,000 cfm (10–20% OA), 8,000 cfm (20–30%), 2,750 cfm (30–40%), or any size at ≥ 40% OA. ERV: 70% sensible, 60% enthalpy minimum at design conditions. |
Local Mechanical Exhaust | Restrooms, laundry rooms, janitor closets, mechanical equipment rooms: exhaust ducted directly to outdoors and certified to ENERGY STAR. | Same |
Thermostats | Programmable, 5F setback | Same |
DHW | Point-of-use electric, UEF ≥ 0.93 | Same |
DHW Piping | R-3 (1.5 in. and smaller); R-4 (larger) | Same |
Water Fixtures | WaterSense: Lav 1.5 GPM; Toilet 1.28 GPF; Urinal 0.5 GPF | Same |
Refrigerator | N/A | ENERGY STAR certified; all-electric |
Dishwasher | N/A | ENERGY STAR certified; all-electric |
Clothes Washer | N/A | ENERGY STAR certified; all-electric |
Clothes Dryer | N/A | ENERGY STAR certified; all-electric |
Stove / Oven | N/A | ENERGY STAR certified; all-electric (no gas) |
Lighting | 100% LED. LPD (W/sqft): Corridor 0.41; Lobby 0.84; Office 0.74; Fitness 0.72; Laundry 0.53; Stair 0.49; Mech/Elec 0.43; Storage 0.38 | Same |
Lighting Controls | Occupancy sensors (corridors/stairs may dim to 50%); auto time switches; daylight controls where zone exceeds 100 W (primary sidelit), 300 W (sidelit), or 100 W (toplit) | Occupancy sensors; auto time switches; daylight controls where zone exceeds 100 W (primary sidelit), 300 W (sidelit), or 100 W (toplit) |
Solar Ready | Solar-ready zone per residential spec (40% roof zone, 5 PSF capacity, conduit + breaker space). | Same |
EV Ready | 20% of installed parking spaces: 40-amp 208/240V dedicated branch circuits, 9.6 kVA minimum; AC Level I substitution allowed at 3:1 ratio. | 10% if dedicated clubhouse-only parking lot; 40-amp 208/240V or equivalent ALMS |
HPWH Ready | N/A | Same |
Electric Readiness | N/A | Same |
Vestibules | Self-closing vestibule at public building entrances; exempt if building under 3,000 sqft, or for employee-only/mechanical room doors, dwelling unit doors, revolving doors, or air curtains. | Same |
Efficiency Credits | 15 credits required. Cold-climate heat pumps (COP ≥ 1.75 at 5°F, electric resistance prohibited except defrost) earn all 15 when meeting all space heating requirements. | Same |
Paperwork & Modeling | COMcheck for common-area envelope, lighting, and mechanical (commercial compliance) plus efficiency-credit documentation. ENERGY STAR workbook, checklists, and common-space HVAC supplement (mandatory). HERS submittals at permit and CO. | COMcheck envelope, lighting, and mechanical certificates. Efficiency-credit documentation. Ventilation calculations. Thermal bridge derating if >20,000 sqft. |
Testing & Verification | Ventilation balancing per design. Duct leakage testing at rough-in and final. HVAC functional testing by FT agent (mandatory). Lighting controls testing. Air barrier inspections. | Same, plus whole-building blower door test ≤ 0.35 CFM/sqft at 75 Pa. |
Exterior Wall (CI)
Exterior Wall (NO CI, NO HPWH)
Slab (All Paths)
Rim Joist (CI)
Rim Joist (NO CI, NO HPWH)
Floor Over Podium (All Paths)
Roof (All Paths)
Path Comparison
This section shows the detailed requirements and incentives for each path we compared, basically showing our work of how we determined the recommended path is the most affordable way of meeting energy code compliance.
Path Comparison - Incentives
NO CI / CI: $410,000
- MassSave Multifamily High Rise Program Energy Star Tier ($358,750) (Program Breakdown): You get this rebate for having your building(s) certified for the Energy Star MFNC v1.2 program. This requires pre-approval via an application to be submitted before construction starts. This rebate comes in the form of a check within 4 months of certification documentation being provided to MassSave, typically this is 4 months after construction is complete.
- In-Unit Heat Pump Water Heater Adder ($51,250) : A MassSave market transformation adder of $250 per unit for installing a heat-pump water heater in each dwelling unit. This rebate comes in the form of a check within 4 months of certification documentation being provided to MassSave, typically this is 4 months after construction is complete.
NO HPWH: $358,750 - $666,250
- MassSave Multifamily High Rise Program Energy Star Tier ($358,750) (Program Breakdown): You get this rebate for having your building(s) certified for the Energy Star MFNC v1.2 program. This requires pre-approval via an application to be submitted before construction starts. This rebate comes in the form of a check within 4 months of certification documentation being provided to MassSave, typically this is 4 months after construction is complete.
- DOER Alternative Energy Credits ($0 - $307,500) (Program Breakdown): This rebate is received for installing APS eligible air source heat pumps (click here for the list). There is an extensive process to get this incentive. It comes in the form of a check approximately 6-12 months after the heat pumps are installed and fully operational.
- IMPORTANT: Although an estimate is provided, this incentive can vary widely typically between $300-1,500 per heat pump. It's based on expected kWh usage of the system as well as the market value of the alternative energy credits when sold.
Path Comparison - Net Cost Summary
Path | Total Cost $/sf | Total Incentives $/sf | Net $/sf | OpEx Factor |
|---|---|---|---|---|
CI | $34.87 | $2.13 | $33.29 | 1.02 |
NO HPWH | $35.13 | $1.86 | $33.57 | 1.01 |
NO CI | $35.57 | $2.13 | $34.05 | 1.02 |
Path Comparison - Envelope
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf | OpEx |
|---|---|---|---|---|---|---|
Exterior Walls | CI | R-21 fiberglass batts, 2x6 @ 16" o.c., with R-9 continuous exterior insulation. | $2.01 | $0.00 | $2.01 | 0.90 |
NO CI | R-38 closed-cell spray foam in a 2x6 @ 16" o.c. cavity, no continuous insulation. | $2.71 | $0.00 | $2.71 | 0.95 | |
NO HPWH | R-38 closed-cell spray foam in a 2x6 @ 16" o.c. cavity, no continuous insulation. | $2.71 | $0.00 | $2.71 | 0.95 | |
Below Grade Walls | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
Corridor Walls | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
Slab | CI | R-10 continuous under-slab insulation; fully insulated. | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | R-10 continuous under-slab insulation; fully insulated. | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | R-10 continuous under-slab insulation; fully insulated. | $0.00 | $0.00 | $0.00 | 1.00 | |
Floor Over Unconditioned Space | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
Floor Over Garage | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
Floor Over Podium | CI | R-30 continuous insulation. | $0.72 | $0.00 | $0.72 | 0.90 |
NO CI | R-30 continuous insulation. | $0.72 | $0.00 | $0.72 | 0.90 | |
NO HPWH | R-30 continuous insulation. | $0.72 | $0.00 | $0.72 | 0.90 | |
Rim Joists | CI | R-21 rim/band insulation at floor transitions. | $0.20 | $0.00 | $0.20 | 0.95 |
NO CI | R-38 rim/band insulation at floor transitions. | $0.20 | $0.00 | $0.20 | 0.95 | |
NO HPWH | R-38 rim/band insulation at floor transitions. | $0.20 | $0.00 | $0.20 | 0.95 | |
Roof | CI | Sealed attic: R-19 cavity insulation + R-30 continuous insulation (roof deck). | $1.05 | $0.00 | $1.05 | 1.10 |
NO CI | Sealed attic: R-19 cavity insulation + R-30 continuous insulation (roof deck). | $1.05 | $0.00 | $1.05 | 1.10 | |
NO HPWH | Sealed attic: R-19 cavity insulation + R-30 continuous insulation (roof deck). | $1.05 | $0.00 | $1.05 | 1.10 | |
Windows & Glass Doors | CI | High performance triple-pane windows, U-0.18 / SHGC 0.18. | $1.31 | $0.00 | $1.31 | 1.00 |
NO CI | High performance triple-pane windows, U-0.18 / SHGC 0.18. | $1.31 | $0.00 | $1.31 | 1.00 | |
NO HPWH | High performance triple-pane windows, U-0.18 / SHGC 0.18. | $1.31 | $0.00 | $1.31 | 1.00 | |
Doors | CI | Opaque: insulated steel, U-0.21 (R-4.75). | $0.35 | $0.00 | $0.35 | 0.95 |
NO CI | Opaque: insulated steel, U-0.21 (R-4.75). | $0.35 | $0.00 | $0.35 | 0.95 | |
NO HPWH | Opaque: insulated steel, U-0.21 (R-4.75). | $0.35 | $0.00 | $0.35 | 0.95 | |
Air Sealing | CI | ≤ 0.27 CFM50 per sqft of enclosure (compartmentalization); tested. | $1.20 | $0.00 | $1.20 | 0.95 |
NO CI | ≤ 0.27 CFM50 per sqft of enclosure (compartmentalization); tested. | $1.20 | $0.00 | $1.20 | 0.95 | |
NO HPWH | ≤ 0.23 CFM50 per sqft of enclosure (compartmentalization); tested. | $1.20 | $0.00 | $1.20 | 0.95 |
Path Comparison - Mechanical
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf | OpEx |
|---|---|---|---|---|---|---|
HVAC | CI | Ductless heat pump (PTHP), through-wall (as modeled); SEER2 13.5; HSPF2 6.8. | $12.37 | $0.00 | $12.37 | 1.15 |
NO CI | Ductless heat pump (PTHP), through-wall (as modeled); SEER2 13.5; HSPF2 6.8. | $12.37 | $0.00 | $12.37 | 1.15 | |
NO HPWH | Ductless mini-split heat pump (as modeled); SEER2 20; HSPF2 10. | $12.98 | $0.00 | $12.98 | 1.15 | |
Ductwork | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
Duct Sealing | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
HVAC Grading | CI | Fan Flow Test: N/A Watt Draw Test: N/A Refrigerant Charge: N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | Fan Flow Test: N/A Watt Draw Test: N/A Refrigerant Charge: N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | Fan Flow Test: N/A Watt Draw Test: N/A Refrigerant Charge: N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
Mechanical Ventilation | CI | In-unit ERV; 30-60 CFM by unit size (studio 30 / 1BR 40 / 2BR 60); ≥ 87% recovery efficiency (Panasonic Intelli-Balance). | $1.86 | $0.00 | $1.86 | 1.20 |
NO CI | In-unit ERV; 30-60 CFM by unit size (studio 30 / 1BR 40 / 2BR 60); ≥ 87% recovery efficiency (Panasonic Intelli-Balance). | $1.86 | $0.00 | $1.86 | 1.20 | |
NO HPWH | In-unit ERV; 30-60 CFM by unit size (studio 30 / 1BR 40 / 2BR 60); ≥ 87% recovery efficiency (Panasonic Intelli-Balance). | $1.86 | $0.00 | $1.86 | 1.20 | |
Local Mechanical Exhaust | CI | Bathroom(s): ≥ 50 CFM intermittent & ≤ 3.0 sones OR ≥ 20 CFM continuous & ≤ 2.0 sones. Kitchen(s): ≥ 100 CFM intermittent & ≤ 3.0 sones OR continuous, ≥ 5 ACH. Both: Exhaust directly outdoors, ENERGY STAR certified. | $1.05 | $0.00 | $1.05 | 1.05 |
NO CI | Bathroom(s): ≥ 50 CFM intermittent & ≤ 3.0 sones OR ≥ 20 CFM continuous & ≤ 2.0 sones. Kitchen(s): ≥ 100 CFM intermittent & ≤ 3.0 sones OR continuous, ≥ 5 ACH. Both: Exhaust directly outdoors, ENERGY STAR certified. | $1.05 | $0.00 | $1.05 | 1.05 | |
NO HPWH | Bathroom(s): ≥ 50 CFM intermittent & ≤ 3.0 sones OR ≥ 20 CFM continuous & ≤ 2.0 sones. Kitchen(s): ≥ 100 CFM intermittent & ≤ 3.0 sones OR continuous, ≥ 5 ACH. Both: Exhaust directly outdoors, ENERGY STAR certified. | $1.05 | $0.00 | $1.05 | 1.05 | |
Thermostats | CI | Programmable thermostat (as modeled). | $0.12 | $0.00 | $0.12 | 1.05 |
NO CI | Programmable thermostat (as modeled). | $0.12 | $0.00 | $0.12 | 1.05 | |
NO HPWH | Programmable thermostat (as modeled). | $0.12 | $0.00 | $0.12 | 1.05 |
Path Comparison - Plumbing & Appliances
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf | OpEx |
|---|---|---|---|---|---|---|
DHW | CI | Integrated heat pump water heater (HPWH) (as modeled); UEF 3.88; 45 gal; in the conditioned corridor; 240V. | $1.98 | $0.27 | $1.71 | 1.20 |
NO CI | Integrated heat pump water heater (HPWH) (as modeled); UEF 3.88; 45 gal; in the conditioned corridor; 240V. | $1.98 | $0.27 | $1.71 | 1.20 | |
NO HPWH | Electric resistance storage water heater (as modeled); UEF 0.93; 44 gal; 240V. | $0.93 | $0.00 | $0.93 | 0.90 | |
DHW Piping | CI | Supply piping insulated to R-3 minimum. | $0.74 | $0.00 | $0.74 | 0.95 |
NO CI | Supply piping insulated to R-3 minimum. | $0.74 | $0.00 | $0.74 | 0.95 | |
NO HPWH | Supply piping insulated to R-3 minimum. | $0.74 | $0.00 | $0.74 | 0.95 | |
Water Fixtures | CI | WaterSense certified (Lavatory ≤1.2 GPM; Shower ≤2.0 GPM; Kitchen ≤2.2 GPM). | $1.86 | $0.00 | $1.86 | 1.00 |
NO CI | WaterSense certified (Lavatory ≤1.2 GPM; Shower ≤2.0 GPM; Kitchen ≤2.2 GPM). | $1.86 | $0.00 | $1.86 | 1.00 | |
NO HPWH | WaterSense certified (Lavatory ≤1.2 GPM; Shower ≤2.0 GPM; Kitchen ≤2.2 GPM). | $1.86 | $0.00 | $1.86 | 1.00 | |
Refrigerator | CI | ≤ 450 kWh/yr (studio & 1BR) / ≤ 550 kWh/yr (2BR); ENERGY STAR; electric. | $0.80 | $0.00 | $0.80 | 1.10 |
NO CI | ≤ 450 kWh/yr (studio & 1BR) / ≤ 550 kWh/yr (2BR); ENERGY STAR; electric. | $0.80 | $0.00 | $0.80 | 1.10 | |
NO HPWH | ≤ 450 kWh/yr (studio & 1BR) / ≤ 550 kWh/yr (2BR); ENERGY STAR; electric. | $0.80 | $0.00 | $0.80 | 1.10 | |
Dishwasher | CI | ≤ 269 kWh/yr; ENERGY STAR; electric. | $0.43 | $0.00 | $0.43 | 1.10 |
NO CI | ≤ 269 kWh/yr; ENERGY STAR; electric. | $0.43 | $0.00 | $0.43 | 1.10 | |
NO HPWH | ≤ 269 kWh/yr; ENERGY STAR; electric. | $0.43 | $0.00 | $0.43 | 1.10 | |
Clothes Washer | CI | IMEF 2.06; ENERGY STAR; electric. | $0.62 | $0.00 | $0.62 | 1.10 |
NO CI | IMEF 2.06; ENERGY STAR; electric. | $0.62 | $0.00 | $0.62 | 1.10 | |
NO HPWH | IMEF 2.06; ENERGY STAR; electric. | $0.62 | $0.00 | $0.62 | 1.10 | |
Clothes Dryer | CI | Electric dryer; ENERGY STAR. | $0.56 | $0.00 | $0.56 | 1.00 |
NO CI | Heat pump electric dryer, ventless; ENERGY STAR. | $0.56 | $0.00 | $0.56 | 1.00 | |
NO HPWH | Heat pump electric dryer, ventless; ENERGY STAR. | $0.56 | $0.00 | $0.56 | 1.00 | |
Stove / Oven | CI | Electric induction cooktop; convection oven. | $0.80 | $0.00 | $0.80 | 1.05 |
NO CI | Electric induction cooktop; convection oven. | $0.80 | $0.00 | $0.80 | 1.05 | |
NO HPWH | Electric induction cooktop; convection oven. | $0.80 | $0.00 | $0.80 | 1.05 |
Path Comparison - Electrical
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf | OpEx |
|---|---|---|---|---|---|---|
Lighting | CI | 100% high-efficacy (LED). | $4.00 | $0.00 | $4.00 | 0.85 |
NO CI | 100% high-efficacy (LED). | $4.00 | $0.00 | $4.00 | 0.85 | |
NO HPWH | 100% high-efficacy (LED). | $4.00 | $0.00 | $4.00 | 0.85 | |
Solar Ready | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
EV Ready | CI | At least 20% of parking spaces wired EV-ready (40-amp Level II; shared circuits with load management allowed). | $0.68 | $0.00 | $0.68 | 1.00 |
NO CI | At least 20% of parking spaces wired EV-ready (40-amp Level II; shared circuits with load management allowed). | $0.68 | $0.00 | $0.68 | 1.00 | |
NO HPWH | At least 20% of parking spaces wired EV-ready (40-amp Level II; shared circuits with load management allowed). | $0.68 | $0.00 | $0.68 | 1.00 | |
HPWH Ready | CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | N/A | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | N/A | $0.00 | $0.00 | $0.00 | 1.00 |
Path Comparison - Soft Costs & Whole-Building Incentives
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf | OpEx |
|---|---|---|---|---|---|---|
Paperwork & Modeling | CI | ENERGY STAR energy model to the target (per-unit HERS or whole-building ASHRAE path), the ENERGY STAR design-review checklist and multifamily workbook, and an HVAC design report. | $0.16 | $1.86 | $-1.70 | 1.00 |
NO CI | ENERGY STAR energy model to the target (per-unit HERS or whole-building ASHRAE path), the ENERGY STAR design-review checklist and multifamily workbook, and an HVAC design report. | $0.16 | $1.86 | $-1.70 | 1.00 | |
NO HPWH | ENERGY STAR energy model to the target (per-unit HERS or whole-building ASHRAE path), the ENERGY STAR design-review checklist and multifamily workbook, and an HVAC design report. | $0.16 | $1.86 | $-1.70 | 1.00 | |
Testing & Verification | CI | ENERGY STAR field verification: pre-drywall and final inspections, unit air-tightness (blower door), and ventilation and exhaust airflow testing. | $0.00 | $0.00 | $0.00 | 1.00 |
NO CI | ENERGY STAR field verification: pre-drywall and final inspections, unit air-tightness (blower door), and ventilation and exhaust airflow testing. | $0.00 | $0.00 | $0.00 | 1.00 | |
NO HPWH | ENERGY STAR field verification: pre-drywall and final inspections, unit air-tightness (blower door), and ventilation and exhaust airflow testing. | $0.00 | $0.00 | $0.00 | 1.00 |
Additional Design Considerations Not Represented In This Study
- Rooftop Solar PV: A rooftop solar array was reviewed as a way to push the HERS score lower. The envelope and all-electric equipment already meet the HERS 45 target without it, with the three paths landing at HERS 43 to 44, and on a six-story, 205-unit building the usable roof area produces little generation per unit against its installed cost. Solar stays out of all three paths and the design is not provisioned as solar-ready.