CS54 Energy Code Feasibility Study in Quincy, Massachusetts

Energy code feasibility study for a 100-unit Multifamily Mid-rise in Massachusetts. Compares multiple design paths. Recommended: Either Path. View full study.

Study Type
Energy Code Feasibility Study
State
Massachusetts
Units
100
Building Type
Multifamily Mid-rise
Fuel Type
All-Electric
Recommended Path
Either Path

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

  • Quincy, MA 02169
  • 100 Units | 191,197 sqft
  • New Construction | Multifamily | Mid-rise
  • All-Electric | Stretch Code | HERS ≤ 45 | Energy Star 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.

Study Summary

We compared two good options for your exterior walls:

  • Continuous & Batt Insulation: Provides a slightly better safety net for your HERS score (about 0.5 extra points).
  • Spray Foam Only (No Continuous): Cheaper and easier to build, but requires a slightly better ERV system.

We recommend getting quotes for both options and deciding based on final cost and constructability. If your HERS score ever falls out of compliance, there is no huge risk, both paths can use HVAC Grading as a backup to gain 2-3 points.

Code Path

Code Path

Permit / Certificate of Occupancy Requirements

Permit / Certificate of Occupancy Requirements

High Rise Buildings

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

MassSave Multifamily High Rise Program Energy Star Tier ($175,000) (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.

MassSave Multifamily Wifi Enabled Thermostat Adder ($10,000) (Program Breakdown): You get this rebate for installing wifi enabled thermostats in your units. 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.

Recommended Design - Units

ItemDetailed Specifications
Exterior Walls2x6 Wood Studs @ 16"oc with R-23 batt cavity + 2" R-10 continuous insulation (Zip R9 OK).
SlabR-10 fully insulated slab; fully covers underside and perimeter of slab.
Floor Over GarageR-30 continuous insulation.
Rim JoistsSeal interior rim cavity with 3" closed-cell spray foam (R-20), continuous insulation to continue without breaking (where continuous insulation cannot continue, use 4.5" of R-30 spray foam).
RoofR-60 Cavity Insulation.
Windows & Glass DoorsU-0.15 / SHGC 0.20, triple pane.
DoorsOpaque: R-4.75.
Air Sealing≤0.30 CFM50 per sqft of shell area, blower-door tested (Air sealing protocol) (Backup Air Sealing)
HVACDucted air-source heat pump, HSPF2 ≥9.5, SEER2 ≥18.5, EER2 ≥12.0.

1BR & 1BR+ = 1.5 ton (18,000 BTU/hr) (product rec).
2BR = 2.0 ton (24,000 BTU/hr) (product rec).
Townhomes & Large 2BR = 2.5 ton (30,000 BTU/hr) (SEER2 rating of this product is only 17.2, acceptable due to increased HSPF2 rating of 10.8, product rec)

Ductless air-source heat pump, HSPF2 ≥11, SEER2 ≥26.3, EER2 ≥15.3; Carrier Infinity Series (Product Rec).

S=1.5 ton (18,000 BTU/hr)

Size per Manual J; Air handler located in conditioned space (mechanical closet).
DuctworkDucts outside conditioned space are to be insulated to R-8 & buried in attic insulation.
Duct SealingDuct total leakage: the greater of 8 CFM25/100 ft² conditioned floor area or 80 CFM25 (duct sealing protocol).
HVAC GradingFan Flow Test: N/A
Watt Draw Test: N/A
Refrigerant Charge: N/A
Mechanical VentilationPanasonic FV-12ESC1 or FV-15ESC1; 85-93% rated recovery.
S: 30 CFM
1BR & 1BR+: 50 CFM
2BR: 70 CFM
Townhomes: 100 CFM
Local Mechanical ExhaustBathroom(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, utilize ERV.
ThermostatsProgrammable thermostat.
DHWElectric resistance storage tank, UEF ≥0.93, 50 gal, located in conditioned space (product rec).
DHW PipingR-3 pipe insulation on all hot water lines.
Maximum hot water pipe run per unit type:
Studio ≤ 26 ft,
1BR ≤ 36 ft,
2BR ≤ 42 ft,
Townhomes ≤ 52 ft.
Targets = 1/2 of refPipeL formula 2·√(CFA/Nfl) + 10·Nfl at largest CFA in each tier.
Water FixturesLow-flow WaterSense certified ≤1.8 GPM showerhead, ≤1.5 GPM lavatory faucet, ≤1.8 GPM kitchen faucet
RefrigeratorENERGY STAR, ≤450 kWh/yr (Studios & 1BR), ≤550 kWh/yr (2BR & 3BR)
DishwasherENERGY STAR, ≤240 kWh/yr, 12 place settings, standard capacity (product rec).
Clothes WasherENERGY STAR electric, ≤99 kWh/yr, IMEF ≥2.92, ≥5.0 cuft capacity, front-load (product rec).
Clothes DryerENERGY STAR heat-pump electric ventless, CEF ≥9, moisture sensing (product rec).
Stove / OvenElectric induction & convection required (product rec).
Lighting100% high-efficacy (LED).
Solar ReadyDesignated Solar Zone: Reserve a contiguous area equal to at least 40% of the total horizontal roof area.
Contiguity: Zone free of obstructions, minimum 5 ft wide.
Structural Capacity: 5 PSF collateral dead load.
Electrical Infrastructure: Conduit pathways and reserved breaker space.
EV ReadyEV Ready infrastructure for at least 20% of total parking. Branch circuit and termination for required spaces, rated for at least 6.2 kVA per space.

N/A
Paperwork & ModelingHERS/ERI energy model, 2021 IECC checklists, ENERGY STAR checklists, incentive documentation.
Testing & VerificationUnit Blower Door Test, Duct Leakage Testing, Mechanical Ventilation Testing, Room Balancing, Predrywall & Final Inspection.

Recommended Design - Common Areas

ItemDetailed Specifications
Exterior Walls2x6 Wood Studs @ 16"oc with R-23 batt cavity + 2" R-10 continuous insulation.
Floor Over GarageR-38 cavity insulation at wood studs.
SlabR-10 fully insulated slab; fully covers underside and perimeter of slab.
Rim JoistsSeal interior rim cavity with 3" closed-cell spray foam (R-20), continuous insulation to continue without breaking (we're continuous insulation cannot continue, use 4.5" of R-30 spray foam).
RoofR-60 Cavity Insulation.
WindowsFixed: U-0.36 / SHGC 0.40
Operable: U-0.43 / SHGC 0.40
DoorsEntrance: U-0.77 / SHGC 0.40; Opaque: U-0.61;
HVACDucted/Ductless split heat pump; SEER2 ≥15.2 / HSPF2 ≥7.8 / EER2 ≥11.7; ENERGY STAR certified; sized per Manual J/S, ≤15% above calculated cooling load.
Duct Sealing<=8 CFM25 per 100 ft² CFA or 80 CFM, whichever is greater.
Mechanical VentilationPer ASHRAE 62.1: Lobby/Office 5 cfm/person + 0.06 cfm/ft²; Fitness 20 cfm/person + 0.18 cfm/ft²; Corridor 0.06 cfm/ft²; Laundry 5 cfm/person + 0.12 cfm/ft². ERV required if total OA intake >=1,000 cfm. Demand controlled ventilation required for spaces >500 ft² with occupancy >25 people per 1,000 ft².
Local Mechanical ExhaustPer ASHRAE 62.1 exhaust rates. Common restrooms, laundry, mechanical rooms as applicable.
ThermostatsProgrammable with 5°F setback capability during unoccupied periods.
DHWPoint-of-use electric water heater for common restroom sinks (if applicable).
DHW PipingPiping insulated to R-3 (<=1.5" pipe) / R-4 (>1.5" pipe).
Water FixturesWaterSense certified: Lavatory <=1.5 GPM; Toilet <=1.28 GPF; Urinal (if installed) <=0.5 GPF.
Lighting100% LED. LPD limits by space: Corridor 0.41 W/ft²; Lobby 0.84; Office 0.74; Fitness 0.63; Community Room 0.59; Laundry 0.53; Stairway 0.49; Mechanical/Electrical 0.43; Storage 0.38.
Lighting ControlsOccupancy/vacancy sensors in all common spaces (corridors/stairs may dim to 50% instead of off). Daylight responsive controls where daylighted area >150 ft². Automatic time switches on all common area lighting.
Solar ReadyPer dwelling unit table (building-wide requirement).
EV ReadyPer dwelling unit table (building-wide requirement).
Paperwork & ModelingCOMcheck report for common areas, ASHRAE 62.1 ventilation calcs, lighting power density calcs.
Testing & VerificationMechanical ventilation balancing, lighting controls commissioning, rough-in and final inspection.

Exterior Wall Assembly (Continuous)

Exterior Wall Assembly (Continuous)

Exterior Wall Assembly (Spray Foam)

Exterior Wall Assembly (Spray Foam)

Rim Joist (Continuous)

Rim Joist (Continuous)

Rim Joist (Spray Foam)

Rim Joist (Spray Foam)

Roof (Both)

Roof (Both)

Slab Edge (Both)

Slab Edge (Both)

Floor Over Garage (Both)

Floor Over Garage (Both)

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

MassSave Multifamily High Rise Program Energy Star Tier ($175,000) (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.

MassSave Multifamily Wifi Enabled Thermostat Adder ($10,000) (Program Breakdown): You get this rebate for installing wifi enabled thermostats in your units. 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.

Path Comparison - Net Cost Summary

PathTotal Cost $/sfTotal Incentives $/sfNet $/sfOpEx FactorWorst HERS$/HERS Point
Spray Foam$55.73$0.97$55.311.0144.391.25
Continuous$57.63$0.97$57.231.0143.931.30

Path Comparison - Envelope

ItemPathDetailed SpecificationsCost $/sfIncentive $/sfNet $/sfOpEx Factor
Exterior WallsSpray Foam2x6 Wood Studs @ 16"oc with R-30 spray foam (3.5" closed cell insulation, 2" open cell insulation).$3.15$0.00$3.150.95
Continuous2x6 Wood Studs @ 16"oc with R-23 batt cavity + 2" R-10 continuous insulation (Zip R9 OK).$4.00$0.00$4.000.95
SlabSpray FoamR-10 fully insulated slab; fully covers underside and perimeter of slab.$1.00$0.00$1.000.90
ContinuousR-10 fully insulated slab; fully covers underside and perimeter of slab.$1.00$0.00$1.000.90
Floor Over GarageSpray FoamR-30 continuous insulation.$1.50$0.00$1.501.00
ContinuousR-30 continuous insulation.$1.50$0.00$1.501.00
Rim JoistsSpray FoamSeal interior rim cavity with 4.5" closed-cell spray foam (R-30).$0.35$0.00$0.350.90
ContinuousSeal interior rim cavity with 3" closed-cell spray foam (R-20), continuous insulation to continue without breaking (we're continuous insulation cannot continue, use 4.5" of R-30 spray foam).$0.40$0.00$0.400.90
RoofSpray FoamR-60 cavity insulation.$1.80$0.00$1.800.95
ContinuousR-60 cavity insulation.$1.80$0.00$1.800.95
Windows & Glass DoorsSpray FoamU-0.15 / SHGC 0.20, triple pane.$15.00$0.00$15.001.10
ContinuousU-0.15 / SHGC 0.20, triple pane.$15.00$0.00$15.001.10
DoorsSpray FoamOpaque: R-4.75.$0.80$0.00$0.800.95
ContinuousOpaque: R-4.75.$0.80$0.00$0.800.95
Air SealingSpray Foam≤0.30 CFM50 per sqft of shell area, blower-door tested (Air sealing protocol) (Backup Air Sealing)$0.60$0.00$0.600.90
Continuous≤0.30 CFM50 per sqft of shell area, blower-door tested (Air sealing protocol) (Backup Air Sealing)$0.60$0.00$0.600.90

Path Comparison - Mechanical

ItemPathDetailed SpecificationsCost $/sfIncentive $/sfNet $/sfOpEx Factor
HVACSpray FoamDucted air-source heat pump, HSPF2 ≥9.5, SEER2 ≥18.5, EER2 ≥12.0.

1BR & 1BR+ = 1.5 ton (18,000 BTU/hr) (product rec).
2BR = 2.0 ton (24,000 BTU/hr) (product rec).
Townhomes & Large 2BR = 2.5 ton (30,000 BTU/hr) (SEER2 rating of this product is only 17.2, acceptable due to increased HSPF2 rating of 10.8, product rec)

Ductless air-source heat pump, HSPF2 ≥11, SEER2 ≥26.3, EER2 ≥15.3; Carrier Infinity Series (Product Rec).

S=1.5 ton (18,000 BTU/hr)
$14.60$0.00$14.601.05
ContinuousDucted air-source heat pump, HSPF2 ≥9.5, SEER2 ≥18.5, EER2 ≥12.0.

1BR & 1BR+ = 1.5 ton (18,000 BTU/hr) (product rec).
2BR = 2.0 ton (24,000 BTU/hr) (product rec).
Townhomes & Large 2BR = 2.5 ton (30,000 BTU/hr) (SEER2 rating of this product is only 17.2, acceptable due to increased HSPF2 rating of 10.8, product rec)

Ductless air-source heat pump, HSPF2 ≥11, SEER2 ≥26.3, EER2 ≥15.3; Carrier Infinity Series (Product Rec).

S=1.5 ton (18,000 BTU/hr)
$14.60$0.00$14.601.05
DuctworkSpray FoamDucts outside conditioned space insulated to R-8 & buried in attic insulation.$1.50$0.00$1.501.00
ContinuousDucts outside conditioned space insulated to R-8 & buried in attic insulation.$1.50$0.00$1.501.00
Duct SealingSpray FoamDuct total leakage: the greater of 8 CFM25/100 ft² conditioned floor area or 80 CFM25 (duct sealing protocol).$0.25$0.00$0.250.95
ContinuousDuct total leakage: the greater of 8 CFM25/100 ft² conditioned floor area or 80 CFM25 (duct sealing protocol).$0.25$0.00$0.250.95
HVAC GradingSpray FoamFan Flow Test: N/A
Watt Draw Test: N/A
Refrigerant Charge: N/A
$0.00$0.00$0.001.00
ContinuousFan Flow Test: N/A
Watt Draw Test: N/A
Refrigerant Charge: N/A
$0.00$0.00$0.001.00
Mechanical VentilationSpray FoamPanasonic FV-12ESC1 or FV-15ESC1; 85-93% rated recovery.
S: 30 CFM
1BR & 1BR+: 50 CFM
2BR: 70 CFM
Townhomes: 100 CFM
$3.50$0.00$3.501.15
ContinuousPanasonic FV-12ESC1 or FV-15ESC1; 85-93% rated recovery.
S: 30 CFM
1BR & 1BR+: 50 CFM
2BR: 70 CFM
Townhomes: 100 CFM
$3.50$0.00$3.501.15
Local Mechanical ExhaustSpray FoamBathroom(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, utilize ERV.
$1.50$0.00$1.501.05
ContinuousBathroom(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, utilize ERV.
$1.50$0.00$1.501.05
ThermostatsSpray FoamProgrammable thermostat.$0.00$0.00$0.001.05
ContinuousProgrammable thermostat.$0.00$0.00$0.001.10

Path Comparison - Plumbing & Appliances

ItemPathDetailed SpecificationsCost $/sfIncentive $/sfNet $/sfOpEx Factor
DHWSpray FoamElectric resistance storage tank, UEF ≥0.93, 50 gal, located in conditioned space (product rec).$1.20$0.00$1.200.90
ContinuousElectric resistance storage tank, UEF ≥0.93, 50 gal, located in conditioned space (product rec).$1.20$0.00$1.200.90
DHW PipingSpray FoamR-3 pipe insulation on all hot water lines.
Maximum hot water pipe run per unit type:
Studio ≤ 26 ft,
1BR ≤ 36 ft,
2BR ≤ 42 ft,
Townhomes ≤ 52 ft.
Targets = 1/2 of refPipeL formula 2·√(CFA/Nfl) + 10·Nfl at largest CFA in each tier.
$0.15$0.00$0.150.95
ContinuousR-3 pipe insulation on all hot water lines.
Maximum hot water pipe run per unit type:
Studio ≤ 26 ft,
1BR ≤ 36 ft,
2BR ≤ 42 ft,
Townhomes ≤ 52 ft.
Targets = 1/2 of refPipeL formula 2·√(CFA/Nfl) + 10·Nfl at largest CFA in each tier.
$0.15$0.00$0.150.95
Water FixturesSpray FoamLow-flow WaterSense certified ≤1.8 GPM showerhead, ≤1.5 GPM lavatory faucet, ≤1.8 GPM kitchen faucet$0.50$0.00$0.501.05
ContinuousLow-flow WaterSense certified ≤1.8 GPM showerhead, ≤1.5 GPM lavatory faucet, ≤1.8 GPM kitchen faucet$0.50$0.00$0.501.05
RefrigeratorSpray FoamENERGY STAR: ≤450 kWh/yr (Studios & 1BR), ≤550 kWh/yr (2BR & 3BR)$0.80$0.00$0.801.00
ContinuousENERGY STAR: ≤450 kWh/yr (Studios & 1BR), ≤550 kWh/yr (2BR & 3BR)$0.80$0.00$0.801.00
DishwasherSpray FoamENERGY STAR, ≤240 kWh/yr, 12 place settings, standard capacity (product rec).$0.45$0.00$0.451.05
ContinuousENERGY STAR, ≤240 kWh/yr, 12 place settings, standard capacity (product rec).$0.45$0.00$0.451.05
Clothes WasherSpray FoamENERGY STAR electric, ≤99 kWh/yr, IMEF ≥2.92, ≥5.0 cuft capacity, front-load (product rec).$0.60$0.00$0.601.15
ContinuousENERGY STAR electric, ≤99 kWh/yr, IMEF ≥2.92, ≥5.0 cuft capacity, front-load (product rec).$0.60$0.00$0.601.15
Clothes DryerSpray FoamENERGY STAR heat-pump electric ventless, CEF ≥9, moisture sensing (product rec).$0.60$0.00$0.601.30
ContinuousENERGY STAR heat-pump electric ventless, CEF ≥9, moisture sensing (product rec).$0.60$0.00$0.601.30
Stove / OvenSpray FoamElectric induction & convection required (product rec).$0.40$0.00$0.401.15
ContinuousElectric induction & convection required (product rec).$0.40$0.00$0.401.15

Path Comparison - Electrical

ItemPathDetailed SpecificationsCost $/sfIncentive $/sfNet $/sfOpEx Factor
LightingSpray Foam100% high-efficacy (LED).$3.50$0.00$3.500.85
Continuous100% high-efficacy (LED).$3.50$0.00$3.500.85
Solar ReadySpray FoamDesignated Solar Zone: Reserve a contiguous area equal to at least 40% of the total horizontal roof area.
Contiguity: Zone free of obstructions, minimum 5 ft wide.
Structural Capacity: 5 PSF collateral dead load.
Electrical Infrastructure: Conduit pathways and reserved breaker space.
$0.05$0.00$0.051.00
ContinuousDesignated Solar Zone: Reserve a contiguous area equal to at least 40% of the total horizontal roof area.
Contiguity: Zone free of obstructions, minimum 5 ft wide.
Structural Capacity: 5 PSF collateral dead load.
Electrical Infrastructure: Conduit pathways and reserved breaker space.
$0.05$0.00$0.051.00
EV ReadySpray FoamEV Ready infrastructure for at least 20% of total parking. Branch circuit and termination for required spaces, rated for at least 6.2 kVA per space.$0.60$0.00$0.601.00
ContinuousEV Ready infrastructure for at least 20% of total parking. Branch circuit and termination for required spaces, rated for at least 6.2 kVA per space.$0.60$0.00$0.601.00
HPWH ReadySpray FoamN/A$0.00$0.00$0.001.00
ContinuousN/A$0.00$0.00$0.001.00

Path Comparison - Soft Costs

ItemPathDetailed SpecificationsCost $/sfIncentive $/sfNet $/sfOpEx Factor
Paperwork & ModelingSpray FoamHERS/ERI energy model, 2021 IECC checklists, ENERGY STAR checklists, incentive documentation.$0.10$0.00$0.101.00
ContinuousHERS/ERI energy model, 2021 IECC checklists, ENERGY STAR checklists, incentive documentation.$0.10$0.00$0.101.00
Testing & VerificationSpray FoamUnit Blower Door Test, Duct Leakage Testing, Mechanical Ventilation Testing, Room Balancing, Predrywall & Final Inspection.$0.23$0.00$0.231.00
ContinuousUnit Blower Door Test, Duct Leakage Testing, Mechanical Ventilation Testing, Room Balancing, Predrywall & Final Inspection.$0.23$0.00$0.231.00

Additional Design Considerations Not Represented In This Study

This study was focused on the comparison between using continuous insulation and not.