CS34 Energy Code Feasibility Study in Medford, Massachusetts
Energy code feasibility study for a 276-unit 6-Story Multifamily Building | 5-story residential over a parking podium. in Massachusetts. Compares multiple design paths. Recommended: GAS. View full study.
- Study Type
- Energy Code Feasibility Study
- State
- Massachusetts
- Units
- 276
- Building Type
- 6-Story Multifamily Building | 5-story residential over a parking podium.
- Fuel Type
- All-Electric
- Recommended Path
- GAS
Goal
To find the most cost-effective compliance path, this report isolates energy code related costs from total construction. We use real MA bid data from vendors & clients to create a reliable framework for aligning incentives and design, with all recommendations confirmed by detailed energy modeling.
Project
- Medford, MA 02155
- 276 Units | 266,261 sqft
- 6-Story Multifamily Building | 5-story residential over a parking podium.
- New Construction | Specialized Opt-In Code | All-Electric or Mixed Fuel
- Phuis CORE 2024 | DOE ENH MF v2 | ENERGY STAR MFNC v1.2 | EPA Indoor airPLUS
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.
SQUEEZE (Recommended) : This all-electric path retains electric resistance water heaters, offsetting the energy penalty by maximizing efficiency in the envelope, HVAC, and appliances. It currently averages a 3.19 HERS score point buffer, ranging from 0.98 to 8.10, (click here to view HERS scores). This path provides the lowest construction cost, no regulatory risk, and great tenant satisfaction. To manage the tight scoring margins in certain units, we have established two contingency plans that can be deployed if finalized window and wall measurements push them out of compliance.
- Contingency Plan: R-21 batt insulation in the exterior wall cavity is not currently needed, but can be used to reduce the HERS score by up to 0.5-points. Once the wall and window measurements are set in stone, the energy models can be updated and it can be determined if this is necessary.
- Worst Case Contingency Plan: If specific units fail, they can be isolated into a separate sample group and upgraded to Heat Pump Water Heaters (+6-8 points). There are 43 units at risk of needing this, but it avoids the need for heat pump water heaters across the entire building, and ensures we have a worst case scenario backup plan. Once the wall and window measurements are set in stone, the energy models can be updated and it can be determined if this is necessary.
GAS : This path uses gas water heaters to boost the HERS score allowing cost reductions across all other requirements. This has a comfortable HERS score buffer, provides superior tenant comfort, and lowers utility bills. However, MA Specialized Code added mixed-fuel requirements add roughly $5.00/sqft ($3.76 is for the required solar system) to the budget and also presents potential long term regulatory risks. Which is why we recommend the SQUEEZE path over this one (click here to view HERS scores).
- Alternate System Option: Ducted systems are can be used as long as the total duct leakage is 80 CFM or less and efficiency ratings meet a minimum 9 HSPF2 across all units, with SEER2 requirements of 17.5 for studios and 1-bedroom units and 17.0 for 2 and 3-bedroom units.
- Contingency Plan: We are currently hitting our targets, but we're keeping HVAC Grade 1 as a 3-point HERS contingency. Once the window and wall measurements are final, we’ll update the energy model; if those changes cause the scores to slip, we can officially add the grading into the scope to make up the difference without changing the design.
- WUFI Passive Model Impact: Replacing electric resistance water heaters with gas-tankless units safely maintains Phius CORE 2024 compliance and improves key metrics:
- Lower Source Energy Penalty: Natural gas carries a lower Source Energy Factor (1.09) than grid electricity (2.0), eliminating the massive penalty currently caused by electric resistance tanks.
- Airtightness Preserved: A stacked venting system minimizes exterior penetrations, making it easier to hit the strict 0.06 CFM50/ft² whole-building airtightness target.
- Thermal Bridging Absorbed: While vertical vent chases must be modeled as linear thermal bridges, the project’s existing 16% buffer on Heating Demand easily absorbs this minor heat loss.
- Solar Credit: The newly added solar PV array provides a Renewable Energy Credit that further lowers the final Source Energy score.
- Massachusetts Specialized Opt-In Code Impact: Adding gas reclassifies the project as a Mixed-Fuel Building under the Commercial Specialized Code, but it remains fully compliant through two strategic inclusions:
- Electrification Pre-wiring: Designing the building to be Heat Pump Water Heater (HPWH) Ready satisfies the code's strict future-proofing and pre-wiring mandates.
- Solar Exception: Mixed-fuel buildings typically require full Net-Zero solar offsets. However, the commercial code grants an exception for limited roof space: installing solar over at least 75% of the Potential Solar Zone Area satisfies the renewable energy requirement.
- Regulatory Risk: While a gas-tankless pathway may currently navigate the WUFI and Specialized Code requirements, it introduces two regulatory risks:
- Future Carbon Emissions Fines Risk: As Building Performance Standards (BPS), similar to Boston’s BERDO, expand across Massachusetts, gas combustion will become a liability. Permanent fossil fuel use exposes ownership to carbon taxes, annual compliance fines, and eventual forced electrification as state caps tighten. By installing the electrical capacity and space for Heat Pump Water Heaters (HPWH) now, the building is future-proofed. If carbon fines eventually are implemented, ownership can swap to electric resistance tanks with minimal capital expenditure.
- Fossil-Fuel Ban Risk: While Medford’s City Council is eager to ban fossil fuels, they are currently restricted by state-level limitations. State-level pilot bans are currently capped to 10 municipalities. If the project is permitted within 12-18 months, it will safely beat the long legislative timeline required for Medford to enact a local ban.
HPWH : This path uses HPWHs to achieve excellent HERS scores, allowing for reduced envelope and HVAC requirements. It’s only difference from the GAS path is the solar system.
- Recommendation: Not recommended unless absolutely necessary. HPWHs are prone to higher maintenance costs and tenant complaints due to noise, cold air exhaust, and slow hot-water recovery times.
- Alternate HVAC / Contingency: Same as the Gas Path (Ducted systems allowed; HVAC Grade 1 reserved as a 3-point HERS contingency).
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
SQUEEZE: $1,142,800 - $1,474,000
- MassSave Passive House Feasibility Study ($5,000): You get this rebate for having a PHIUS feasibility study completed for your project & having a 1 hour charette with the design team and MassSave representative to review that study. This process must be completed before construction is complete. This rebate comes in the form of a check within 4 months of the charette taking place.
- IMPORTANT: The incentive is capped at 100% of the applicable service charge.
- MassSave Passive House Energy Model ($20,000): You get this rebate for having a PHIUS feasibility study completed for your project & having a 1 hour charette with the design team and MassSave representative to review that study. This process must be completed before construction is complete. This rebate comes in the form of a check within 4 months of the 1 hour meeting taking place.
- IMPORTANT: The incentive is capped at 75% of the applicable service charge.
- MassSave Passive House Pre-Certification ($207,000): You get this rebate for having your project PHIUS pre-certified. Pre-Certification typically occurs toward the end of the pre-construction phase. This rebate comes in the form of a check within 4 months of the pre-certification paperwork being provided to MassSave.
- MassSave Passive House Certification ($828,000): You get this rebate for having your project PHIUS certified. Certification typically occurs at the end of construction around when certificate of occupancy is received. This rebate comes in the form of a check within 4 months of the certification paperwork being provided to MassSave.
- DOER Alternative Energy Credits ($82,800 - $414,000): This rebate is received for installing APS eligible air source heat pumps. 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.
Recommended Design - Units & Common Areas
Item | Detailed Specifications |
|---|---|
Exterior Walls | 3" PolyIso Rigid Continuous Insulation (R-20.3) installed on the outside of 2x6 wood-framed walls. (Product Ref) |
Floor Over Unconditioned Space | 6-inch Continuous Insulation (R-21) installed on the underside of the concrete podium deck. |
Rim Joists | Seal interior rim cavity with minimum 2" closed-cell spray foam for air sealing and thermal performance. 3" PolyIso Rigid Continuous Insulation (R-20.3) shall continue over floor transitions without interruption. |
Roof | 10-inch Rigid Polyiso Continuous Insulation (R-60) installed in multiple layers with staggered joints on the roof deck. (Product Ref) |
Windows | Fixed: U-0.142 / SHGC 0.32 Operable: U-0.165 / SHGC 0.20 Patio: U-0.18 / SHGC 0.20 |
Doors | Glazed: U-0.18 / SHGC 0.20; Opaque: U-0.21 (R-4.75); |
Air Sealing | Units: ≤ 0.20 CFM50/sqft; Whole Building: ≤ 0.06 CFM50/sqft; (Airbarrier) (Air sealing protocol) (Backup plan) |
HVAC | S & 1 Bed: Ductless split heat pump; SEER2 26.2; HSPF2 12; (Product Ref) 2 & 3Bed: Ductless split heat pump; SEER2 23.5; HSPF2 10.5; (Product Ref) |
Duct Sealing | N/A |
HVAC Grading | Fan Flow Test: Grade 1 (Exempt - Ductless System). Watt Draw Test: Grade 1 (≤ 0.45 W/CFM). Refrigerant Charge: Grade 1 (≤ 5% deviation from design charge weight by scale). |
Mechanical Ventilation | S & 1 Bed: 50 CFM, 1.92 CFM/Watt, 90% rated recovery; (Product Ref) 2 & 3 Bed: 75 CFM, 1.98 CFM/Watt, 85% rated recovery; (Product Ref) |
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 Based on kitchen volume & ≤ 1.0 sone. Both: Exhaust directly outdoors, ENERGY STAR certified, utilize ERV to meet these requirements. |
Thermostats | Programmable Thermostat (Product Ref) |
DHW | Electric tank heater in unit (UEF ≥0.94) (Product Ref) |
DHW Piping | Supply piping insulated to R-3 minimum; Max 1.8 gallons stored volume per run; Modeled pipe runs are optimized to 1/3 program default lengths; (click here to see max run lengths). |
Water Fixtures | Watersense Certified Fixtures (Lavatory: ≤1.2 GPM, Shower: ≤2.0 GPM) |
Refrigerator | S & 1 Bed: ≤ 451 kWh annual usage; ENERGY STAR; Electric; (Product Ref) 2 & 3 Bed: ≤ 550 kWh annual usage; ENERGY STAR; Electric; (Product Ref) |
Dishwasher | All: ≤ 240 kWh annual usage; ENERGY STAR; Electric; (Low Cost Product Ref) (Luxury Product Ref) |
Clothes Washer | All: ≤ 99 kWh annual usage; ≥ 2.92 IMEF; ≥ 5 cubic ft capacity; ENERGY STAR; Electric; (Product Ref) |
Clothes Dryer | All: ≥ 9 CEF; Ventless; Heat Pump Dryer; ENERGY STAR; Electric; (Product Ref) |
Stove / Oven | Induction Stovetop & Convection Oven; Electric; (Product Ref) |
Lighting | 100% high-efficacy (LED) |
Solar Ready | Designated Solar Zone: Reserve a contiguous area equal to at least 40% of the total horizontal roof area (after excluding skylights, occupied decks, vegetated areas, and fire setbacks). Contiguity & Obstructions: The zone must be free of all obstructions (pipes, vents, HVAC units) and maintain a minimum width of 5 feet. Structural Capacity: Roof structures within this zone must be engineered to support a future collateral dead load of 5 PSF. Orientation (Sloped Roofs): For roofs with a pitch of 4:12 or greater, the zone must be oriented between 110° and 270° of true north. Electrical Infrastructure: Provide identified conduit pathways from the roof to the electrical service and reserve a labeled space for a dual-pole circuit breaker in the main panel or common space service. |
EV Ready | Requirement: Provide EV Ready infrastructure for at least 20% of total parking. At least 10% of total spaces must have Active Level 2 EV Chargers (EVSE) fully installed and functional. Compliance is achieved through: Standard Level 2 Active (10%): Install functional Level 2 EVSE hardware in 10% of total spaces, ensuring a nameplate charging capacity of not less than 6.2 kVA (or 30A at 208/240V) per space. Standard Level 2 Ready (Remainder): Provide a branch circuit and termination for the remaining required spaces (up to 20% total), rated for a system capacity of at least 6.2 kVA per space. Load Management (EMS) Option: If an Energy Management System (EMS) is used to share power between multiple spaces, the required system capacity and EVSE nameplate rating may be reduced to 2.1 kVA per space. |
HPWH Ready | N/A |
Paperwork & Modeling | WUFI & HERS / ERI Energy model, 2021 IECC checklists, ENERGY STAR MFNC checklists, Efficient New Homes checklists, PHIUS checklists, PHIUS Feasibility Study, and incentive documentation. |
Testing & Verification | Whole Building & Unit Blower Door Test, Mechanical Ventilation Testing, Fan Flow (exempt), Watt Draw, Refrigerant Charge, Room Balancing, Slab, Predrywall & Final Inspection. |
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
SQUEEZE / GAS / HPWH: $1,142,800 - $1,474,000
- MassSave Passive House Feasibility Study ($5,000): You get this rebate for having a PHIUS feasibility study completed for your project & having a 1 hour charette with the design team and MassSave representative to review that study. This process must be completed before construction is complete. This rebate comes in the form of a check within 4 months of the charette taking place.
- IMPORTANT: The incentive is capped at 100% of the applicable service charge.
- MassSave Passive House Energy Model ($20,000): You get this rebate for having a PHIUS feasibility study completed for your project & having a 1 hour charette with the design team and MassSave representative to review that study. This process must be completed before construction is complete. This rebate comes in the form of a check within 4 months of the 1 hour meeting taking place.
- IMPORTANT: The incentive is capped at 75% of the applicable service charge.
- MassSave Passive House Pre-Certification ($207,000): You get this rebate for having your project PHIUS pre-certified. Pre-Certification typically occurs toward the end of the pre-construction phase. This rebate comes in the form of a check within 4 months of the pre-certification paperwork being provided to MassSave.
- MassSave Passive House Certification ($828,000): You get this rebate for having your project PHIUS certified. Certification typically occurs at the end of construction around when certificate of occupancy is received. This rebate comes in the form of a check within 4 months of the certification paperwork being provided to MassSave.
- DOER Alternative Energy Credits ($82,800 - $414,000): This rebate is received for installing APS eligible air source heat pumps. 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 |
|---|---|---|---|
SQUEEZE | $35.11 | $4.50 | $30.61 |
GAS | $41.14 | $4.50 | $36.64 |
HPWH | $36.20 | $4.50 | $31.70 |
Path Comparison - Envelope
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf |
|---|---|---|---|---|---|
Exterior Walls | SQUEEZE | 3" PolyIso Rigid Continuous Insulation (R-20.3) installed on the outside of 2x6 wood-framed walls. (Product Ref) | $0.68 | $0.00 | $0.68 |
GAS | 3-inch Rigid Stone Wool Continuous Insulation (R-12.6) installed on the outside of 2x6 wood-framed walls. (Product Ref) | $1.11 | $0.00 | $1.11 | |
HPWH | 3-inch Rigid Stone Wool Continuous Insulation (R-12.6) installed on the outside of 2x6 wood-framed walls. (Product Ref) | $1.11 | $0.00 | $1.11 | |
Floor Over Unconditioned Space | SQUEEZE | 6-inch Continuous Insulation (R-21) installed on the underside of the concrete podium deck. | $1.33 | $0.00 | $1.33 |
GAS | 6-inch Continuous Insulation (R-21) installed on the underside of the concrete podium deck. | $1.33 | $0.00 | $1.33 | |
HPWH | 6-inch Continuous Insulation (R-21) installed on the underside of the concrete podium deck. | $1.33 | $0.00 | $1.33 | |
Rim Joists | SQUEEZE | Seal interior rim cavity with minimum 2" closed-cell spray foam for air sealing and thermal performance. 3" PolyIso Rigid Continuous Insulation (R-20.3) shall continue over floor transitions without interruption. | $0.14 | $0.00 | $0.14 |
GAS | Seal interior rim cavity with minimum 2" closed-cell spray foam for air sealing and thermal performance. 3" Rigid Stone Wool continuous insulation (R-12.6) shall continue over floor transitions without interruption. | $0.19 | $0.00 | $0.19 | |
HPWH | Seal interior rim cavity with minimum 2" closed-cell spray foam for air sealing and thermal performance. 3" Rigid Stone Wool continuous insulation (R-12.6) shall continue over floor transitions without interruption. | $0.19 | $0.00 | $0.19 | |
Roof | SQUEEZE | 10-inch Rigid Polyiso Continuous Insulation (R-60) installed in multiple layers with staggered joints on the roof deck. (Product Ref) | $2.00 | $0.00 | $2.00 |
GAS | 10-inch Rigid Polyiso Continuous Insulation (R-60) installed in multiple layers with staggered joints on the roof deck. (Product Ref) | $2.00 | $0.00 | $2.00 | |
HPWH | 10-inch Rigid Polyiso Continuous Insulation (R-60) installed in multiple layers with staggered joints on the roof deck. (Product Ref) | $2.00 | $0.00 | $2.00 | |
Windows | SQUEEZE | Fixed: U-0.142 / SHGC 0.32 Operable: U-0.165 / SHGC 0.20 Patio: U-0.18 / SHGC 0.20 | $4.68 | $0.00 | $4.68 |
GAS | Fixed: U-0.142 / SHGC 0.32 Operable: U-0.165 / SHGC 0.20 Patio: U-0.18 / SHGC 0.20 | $4.68 | $0.00 | $4.68 | |
HPWH | Fixed: U-0.142 / SHGC 0.32 Operable: U-0.165 / SHGC 0.20 Patio: U-0.18 / SHGC 0.20 | $4.68 | $0.00 | $4.68 | |
Doors | SQUEEZE | Glazed: U-0.18 / SHGC 0.20; Opaque: U-0.21 (R-4.75); | $0.56 | $0.00 | $0.56 |
GAS | Glazed: U-0.18 / SHGC 0.20; Opaque: U-0.21 (R-4.75); | $0.56 | $0.00 | $0.56 | |
HPWH | Glazed: U-0.18 / SHGC 0.20; Opaque: U-0.21 (R-4.75); | $0.56 | $0.00 | $0.56 | |
Air Sealing | SQUEEZE | Units: ≤ 0.20 CFM50/sqft; Whole Building: ≤ 0.06 CFM50/sqft; (Airbarrier) (Air sealing protocol) (Backup plan) | $0.60 | $0.00 | $0.60 |
GAS | Units: ≤ 0.30 CFM50/sqft; Whole Building: ≤ 0.06 CFM50/sqft; (Airbarrier) (Air sealing protocol) (Backup plan) | $0.40 | $0.00 | $0.40 | |
HPWH | Units: ≤ 0.30 CFM50/sqft; Whole Building: ≤ 0.06 CFM50/sqft; (Airbarrier) (Air sealing protocol) (Backup plan) | $0.40 | $0.00 | $0.40 |
Path Comparison - Mechanical
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf |
|---|---|---|---|---|---|
HVAC | SQUEEZE | S & 1 Bed: Ductless split heat pump; SEER2 26.2; HSPF2 12; (Product Ref) 2 & 3Bed: Ductless split heat pump; SEER2 23.5; HSPF2 10.5; (Product Ref) | $8.81 | $0.52 | $8.29 |
GAS | S & 1 Bed: Ductless split heat pump; SEER2 19.3 HSPF2 10; (Product Ref) 2 & 3Bed: Ductless split heat pump; SEER2 18.55; HSPF9.4; (Product Ref) | $7.26 | $0.52 | $6.74 | |
HPWH | S & 1 Bed: Ductless split heat pump; SEER2 19.3 HSPF2 10; (Product Ref) 2 & 3Bed: Ductless split heat pump; SEER2 18.55; HSPF9.4; (Product Ref) | $7.26 | $0.52 | $6.74 | |
Duct Sealing | SQUEEZE | N/A | $0.00 | $0.00 | $0.00 |
GAS | $0.00 | $0.00 | $0.00 | ||
HPWH | $0.00 | $0.00 | $0.00 | ||
HVAC Grading | SQUEEZE | Fan Flow Test: Grade 1 (Exempt - Ductless System). Watt Draw Test: Grade 1 (≤ 0.45 W/CFM). Refrigerant Charge: Grade 1 (≤ 5% deviation from design charge weight by scale). | $0.00 | $0.00 | $0.00 |
GAS | Fan Flow Test: N/A Watt Draw Test: N/A Refrigerant Charge: N/A | $0.00 | $0.00 | $0.00 | |
HPWH | Fan Flow Test: N/A Watt Draw Test: N/A Refrigerant Charge: N/A | $0.00 | $0.00 | $0.00 | |
Mechanical Ventilation | SQUEEZE | S & 1 Bed: 50 CFM, 1.92 CFM/Watt, 90% rated recovery; (Product Ref) 2 & 3 Bed: 75 CFM, 1.98 CFM/Watt, 85% rated recovery; (Product Ref) | $2.28 | $0.00 | $2.28 |
GAS | S & 1 Bed: 50 CFM, 1.92 CFM/Watt, 90% rated recovery; (Product Ref) 2 & 3 Bed: 75 CFM, 1.98 CFM/Watt, 85% rated recovery; (Product Ref) | $2.28 | $0.00 | $2.28 | |
HPWH | S & 1 Bed: 50 CFM, 1.92 CFM/Watt, 90% rated recovery; (Product Ref) 2 & 3 Bed: 75 CFM, 1.98 CFM/Watt, 85% rated recovery; (Product Ref) | $2.28 | $0.00 | $2.28 | |
Local Mechanical Exhaust | SQUEEZE | 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 Based on kitchen volume & ≤ 1.0 sone. Both: Exhaust directly outdoors, ENERGY STAR certified, utilize ERV to meet these requirements. | $0.00 | $0.00 | $0.00 |
GAS | 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 Based on kitchen volume & ≤ 1.0 sone. Both: Exhaust directly outdoors, ENERGY STAR certified, utilize ERV to meet these requirements. | $0.00 | $0.00 | $0.00 | |
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 Based on kitchen volume & ≤ 1.0 sone. Both: Exhaust directly outdoors, ENERGY STAR certified, utilize ERV to meet these requirements. | $0.00 | $0.00 | $0.00 | |
Thermostats | SQUEEZE | Programmable Thermostat (Product Ref) | $0.41 | $0.00 | $0.41 |
GAS | Programmable Thermostat (Product Ref) | $0.26 | $0.00 | $0.26 | |
HPWH | Programmable Thermostat (Product Ref) | $0.26 | $0.00 | $0.26 |
Path Comparison - Plumbing & Appliances
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf |
|---|---|---|---|---|---|
DHW | SQUEEZE | Electric tank heater in unit (UEF ≥0.94) (Product Ref) | $2.28 | $0.00 | $2.28 |
GAS | Gas tankless heater in unit (UEF ≥0.95) (Product Ref) | $4.66 | $0.00 | $4.66 | |
HPWH | S & 1 Bed: HPWH In Unit OR Corridor (UEF ≥3.88; 50 Gal) (Product Ref) 2 & 3 Bed: HPWH In Unit OR Corridor (UEF ≥4.07; 80 Gal) (Product Ref) | $4.66 | $0.00 | $4.66 | |
DHW Piping | SQUEEZE | Supply piping insulated to R-3 minimum; Max 1.8 gallons stored volume per run; Modeled pipe runs are optimized to 1/3 program default lengths; (click here to see max run lengths). | $1.20 | $0.00 | $1.20 |
GAS | Supply piping insulated to R-3 minimum; Max 1.8 gallons stored volume per run; Modeled pipe runs are optimized to 1/3 program default lengths; (click here to see max run lengths). | $1.20 | $0.00 | $1.20 | |
HPWH | Supply piping insulated to R-3 minimum; Max 1.8 gallons stored volume per run; Modeled pipe runs are optimized to 1/3 program default lengths; (click here to see max run lengths). | $1.20 | $0.00 | $1.20 | |
Water Fixtures | SQUEEZE | Watersense Certified Fixtures (Lavatory: ≤1.2 GPM, Shower: ≤2.0 GPM) | $0.15 | $0.00 | $0.15 |
GAS | Watersense Certified Fixtures (Lavatory: ≤1.2 GPM, Shower: ≤2.0 GPM) | $0.15 | $0.00 | $0.15 | |
HPWH | Watersense Certified Fixtures (Lavatory: ≤1.2 GPM, Shower: ≤2.0 GPM) | $0.15 | $0.00 | $0.15 | |
Refrigerator | SQUEEZE | S & 1 Bed: ≤ 451 kWh annual usage; ENERGY STAR; Electric; (Product Ref) 2 & 3 Bed: ≤ 550 kWh annual usage; ENERGY STAR; Electric; (Product Ref) | $0.85 | $0.00 | $0.85 |
GAS | All: ≤ 600 kWh annual usage; ENERGY STAR; Electric; (Product Ref) | $0.98 | $0.00 | $0.98 | |
HPWH | All: ≤ 600 kWh annual usage; ENERGY STAR; Electric; (Product Ref) | $0.98 | $0.00 | $0.98 | |
Dishwasher | SQUEEZE | All: ≤ 240 kWh annual usage; ENERGY STAR; Electric; (Low Cost Product Ref) (Luxury Product Ref) | $0.62 | $0.00 | $0.62 |
GAS | All: ≤ 240 kWh annual usage; ENERGY STAR; Electric; (Low Cost Product Ref) (Luxury Product Ref) | $0.62 | $0.00 | $0.62 | |
HPWH | All: ≤ 240 kWh annual usage; ENERGY STAR; Electric; (Low Cost Product Ref) (Luxury Product Ref) | $0.62 | $0.00 | $0.62 | |
Clothes Washer | SQUEEZE | All: ≤ 99 kWh annual usage; ≥ 2.92 IMEF; ≥ 5 cubic ft capacity; ENERGY STAR; Electric; (Product Ref) | $1.24 | $0.00 | $1.24 |
GAS | All: ≤ 99 kWh annual usage; ≥ 2.92 IMEF; ≥ 5 cubic ft capacity; ENERGY STAR; Electric; (Product Ref) | $1.24 | $0.00 | $1.24 | |
HPWH | All: ≤ 99 kWh annual usage; ≥ 2.92 IMEF; ≥ 5 cubic ft capacity; ENERGY STAR; Electric; (Product Ref) | $1.24 | $0.00 | $1.24 | |
Clothes Dryer | SQUEEZE | All: ≥ 9 CEF; Ventless; Heat Pump Dryer; ENERGY STAR; Electric; (Product Ref) | $1.24 | $0.00 | $1.24 |
GAS | All: ≥ 9 CEF; Ventless; Heat Pump Dryer; ENERGY STAR; Electric; (Product Ref) | $1.24 | $0.00 | $1.24 | |
HPWH | All: ≥ 9 CEF; Ventless; Heat Pump Dryer; ENERGY STAR; Electric; (Product Ref) | $1.24 | $0.00 | $1.24 | |
Stove / Oven | SQUEEZE | Induction Stovetop & Convection Oven; Electric; (Product Ref) | $3.21 | $0.00 | $3.21 |
GAS | Induction Stovetop & Convection Oven; Electric; (Product Ref) | $3.21 | $0.00 | $3.21 | |
HPWH | Induction Stovetop & Convection Oven; Electric; (Product Ref) | $3.21 | $0.00 | $3.21 |
Path Comparison - Electrical
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf |
|---|---|---|---|---|---|
Lighting | SQUEEZE | 100% high-efficacy (LED) | $0.85 | $0.00 | $0.85 |
GAS | 100% high-efficacy (LED) | $0.85 | $0.00 | $0.85 | |
HPWH | 100% high-efficacy (LED) | $0.85 | $0.00 | $0.85 | |
Solar Ready | SQUEEZE | Designated Solar Zone: Reserve a contiguous area equal to at least 40% of the total horizontal roof area (after excluding skylights, occupied decks, vegetated areas, and fire setbacks). Contiguity & Obstructions: The zone must be free of all obstructions (pipes, vents, HVAC units) and maintain a minimum width of 5 feet. Structural Capacity: Roof structures within this zone must be engineered to support a future collateral dead load of 5 PSF. Orientation (Sloped Roofs): For roofs with a pitch of 4:12 or greater, the zone must be oriented between 110° and 270° of true north. Electrical Infrastructure: Provide identified conduit pathways from the roof to the electrical service and reserve a labeled space for a dual-pole circuit breaker in the main panel or common space service. | $0.06 | $0.00 | $0.06 |
GAS | Install a solar system that uses either 0.75 W/ft² of conditioned floor area OR 75% of available solar ready roof zone. | $3.76 | $0.00 | $3.76 | |
HPWH | Designated Solar Zone: Reserve a contiguous area equal to at least 40% of the total horizontal roof area (after excluding skylights, occupied decks, vegetated areas, and fire setbacks). Contiguity & Obstructions: The zone must be free of all obstructions (pipes, vents, HVAC units) and maintain a minimum width of 5 feet. Structural Capacity: Roof structures within this zone must be engineered to support a future collateral dead load of 5 PSF. Orientation (Sloped Roofs): For roofs with a pitch of 4:12 or greater, the zone must be oriented between 110° and 270° of true north. Electrical Infrastructure: Provide identified conduit pathways from the roof to the electrical service and reserve a labeled space for a dual-pole circuit breaker in the main panel or common space service. | $0.06 | $0.00 | $0.06 | |
EV Ready | SQUEEZE | Requirement: Provide EV Ready infrastructure for at least 20% of total parking. At least 10% of total spaces must have Active Level 2 EV Chargers (EVSE) fully installed and functional. Compliance is achieved through: Standard Level 2 Active (10%): Install functional Level 2 EVSE hardware in 10% of total spaces, ensuring a nameplate charging capacity of not less than 6.2 kVA (or 30A at 208/240V) per space. Standard Level 2 Ready (Remainder): Provide a branch circuit and termination for the remaining required spaces (up to 20% total), rated for a system capacity of at least 6.2 kVA per space. Load Management (EMS) Option: If an Energy Management System (EMS) is used to share power between multiple spaces, the required system capacity and EVSE nameplate rating may be reduced to 2.1 kVA per space. | $0.27 | $0.00 | $0.27 |
GAS | Requirement: Provide EV Ready infrastructure for at least 20% of total parking. At least 10% of total spaces must have Active Level 2 EV Chargers (EVSE) fully installed and functional. Compliance is achieved through: Standard Level 2 Active (10%): Install functional Level 2 EVSE hardware in 10% of total spaces, ensuring a nameplate charging capacity of not less than 6.2 kVA (or 30A at 208/240V) per space. Standard Level 2 Ready (Remainder): Provide a branch circuit and termination for the remaining required spaces (up to 20% total), rated for a system capacity of at least 6.2 kVA per space. Load Management (EMS) Option: If an Energy Management System (EMS) is used to share power between multiple spaces, the required system capacity and EVSE nameplate rating may be reduced to 2.1 kVA per space. | $0.27 | $0.00 | $0.27 | |
HPWH | Requirement: Provide EV Ready infrastructure for at least 20% of total parking. At least 10% of total spaces must have Active Level 2 EV Chargers (EVSE) fully installed and functional. Compliance is achieved through: Standard Level 2 Active (10%): Install functional Level 2 EVSE hardware in 10% of total spaces, ensuring a nameplate charging capacity of not less than 6.2 kVA (or 30A at 208/240V) per space. Standard Level 2 Ready (Remainder): Provide a branch circuit and termination for the remaining required spaces (up to 20% total), rated for a system capacity of at least 6.2 kVA per space. Load Management (EMS) Option: If an Energy Management System (EMS) is used to share power between multiple spaces, the required system capacity and EVSE nameplate rating may be reduced to 2.1 kVA per space. | $0.27 | $0.00 | $0.27 | |
HPWH Ready | SQUEEZE | N/A | $0.00 | $0.00 | $0.00 |
GAS | Electric Requirement: A dedicated branch circuit (minimum 240V/30A or 120V/20A) must terminate within 3 feet of the heater. Space Requirement: A minimum open space of 3' x 3' x 7' must be available surrounding or within 3 feet of the heater to facilitate a future heat pump unit. Condensate Drain: A drain must be installed within 3 feet of the existing heater. | $1.24 | $0.00 | $1.24 | |
HPWH | N/A | $0.00 | $0.00 | $0.00 |
Path Comparison - Soft Costs
Item | Path | Detailed Specifications | Cost $/sf | Incentive $/sf | Net $/sf |
|---|---|---|---|---|---|
Paperwork & Modeling | SQUEEZE | WUFI & HERS / ERI Energy model, 2021 IECC checklists, ENERGY STAR MFNC checklists, Efficient New Homes checklists, PHIUS checklists, PHIUS Feasibility Study, and incentive documentation. | $1.03 | $0.87 | $0.16 |
GAS | WUFI & HERS / ERI Energy model, 2021 IECC checklists, ENERGY STAR MFNC checklists, Efficient New Homes checklists, PHIUS checklists, PHIUS Feasibility Study, and incentive documentation. | $1.03 | $0.87 | $0.16 | |
HPWH | WUFI & HERS / ERI Energy model, 2021 IECC checklists, ENERGY STAR MFNC checklists, Efficient New Homes checklists, PHIUS checklists, PHIUS Feasibility Study, and incentive documentation. | $1.03 | $0.87 | $0.16 | |
Testing & Verification | SQUEEZE | Whole Building & Unit Blower Door Test, Mechanical Ventilation Testing, Fan Flow (exempt), Watt Draw, Refrigerant Charge, Room Balancing, Slab, Predrywall & Final Inspection. | $0.62 | $3.11 | -$2.49 |
GAS | Whole Building & Unit Blower Door Test, Duct Test Total (As-Needed), Mechanical Ventilation Testing, Fan Flow (exempt), Watt Draw, Refrigerant Charge, Room Balancing, Slab, Predrywall & Final Inspection. | $0.62 | $3.11 | -$2.49 | |
HPWH | Whole Building & Unit Blower Door Test, Duct Test Total (As-Needed), Mechanical Ventilation Testing, Fan Flow (exempt), Watt Draw, Refrigerant Charge, Room Balancing, Slab, Predrywall & Final Inspection. | $0.62 | $3.11 | -$2.49 |
Additional Design Considerations Not Represented In This Study
- Exterior Wall Cavity Spray Foam: Standard 5.5-inch batt insulation provides R-21 more cost-effectively. Upgrading to closed-cell spray foam for maximum R-value of R-38 was assessed but offered a negligible improvement of less than 0.1 HERS points. Given the significant cost increase and lack of energy modeling benefit, standard batts remained the basis of design, although cavity insulation in the exterior walls was ruled unnecessary altogether.
- Podium Drop Ceiling: An R-30 drop ceiling offers a superior U-factor at a lower cost than current methods. However, it was not considered due to potential thermal bridging complications in the WUFI model.
- Centralized HPWH & Gas Water Heating: These provide a significant improvement in the HERS score but the cost & complexity of these systems in addition to the space requirements made them a non-starter.
- Tankless Electric Hot Water: Despite an improved 0.98 UEF, these units negatively impacted HERS scores. They are more expensive and perform worse in energy models than standard electric resistance tanks
- Induction & Convection Ranges: Upgrading to induction stovetops provides a 1-point HERS reduction. Adding a convection oven provides an additional 0.5-point HERS reduction for a minimal cost increase.
- Standard Electric Dryer: Upgrading from standard electric to heat pump dryers improves the HERS score by up to 2 points. The higher equipment cost is offset by simpler installation (no venting) and critical energy savings.
- High-Efficiency Dishwashers: Reducing annual dishwasher usage below 200 kWh provided less than a 0.2-point HERS improvement. The high cost of these units and the potential move to compact sizes do not align with the luxury apartment feel.
- Aggressive In-Unit Air Sealing: Reducing infiltration from 0.20 to 0.10 CFM50/sqft produced zero HERS score reduction. Given the extreme cost, technical difficulty, and risk, the target remains 0.20 CFM50/sqft.