Stretch Code Report for Building Permits in Somerville, MA

What the Building Department Is Asking For

Most people have never heard the words "HERS rating" until the building department asks for one. These all mean the same report:

Stretch code report or stretch energy code report
Energy report or energy compliance report for the permit
HERS report, projected HERS rating or ERI report
Energy code compliance letter

Under the Massachusetts Stretch Code (225 CMR 22), new homes and large additions show compliance with a HERS Index score at or below the code target. The score has to come from a RESNET-certified HERS rater, and the code requires third-party verification.

What Is in Your Permit Report

A projected HERS report the building inspector can check in a few minutes.

The projected HERS Index score next to the code target for your project
The compliance path: Stretch Code or Specialized Code, mixed-fuel or all-electric
Insulation R-values, window U-factors and air sealing targets used in the model
Heating, cooling, hot water and ventilation equipment
The blower door target (3.0 ACH50 for new homes) and duct leakage target the house must hit at final
The rater's name and RESNET ID

Sample projected HERS rating certificate showing a HERS Index score of 45 - stretch code report for a building permit in Somerville, MA

Which Report Do You Need? Residential vs. Commercial

The building type decides the report. Homes and low-rise residential buildings follow 225 CMR 22. Commercial buildings and larger multifamily buildings follow 225 CMR 23.

Project	What goes in with the permit	Testing at the end
New single-family home, two-family, townhouse or ADU	Projected HERS rating report (or Passive House)	Blower door, duct leakage, confirmed HERS certificate
Addition over 1,000 sq ft or over 100% of the home, or an extensive alteration over 1,000 sq ft (R503.1.5)	Projected HERS rating report (what triggers a HERS rating)	Blower door, duct leakage, confirmed HERS certificate
Smaller residential addition or alteration	REScheck or the prescriptive path, if the inspector accepts it	Per the building department
Commercial building up to 20,000 sq ft	COMcheck (prescriptive path, C401.2.1). See REScheck vs. COMcheck.	Whole-building blower door test: 0.35 cfm/sq ft at 75 Pa (C402.5.2)
Commercial building over 20,000 sq ft	Energy modeling: Targeted Performance (TEDI), Relative Performance or Passive House. COMcheck alone is not enough.	Whole-building blower door test
Multifamily over 12,000 sq ft	Specialized Code towns: Passive House (Phius) certification. Stretch Code towns: Passive House, a HERS rating, or TEDI energy modeling (C401.2).	Phius or HERS testing (sampling allowed over 8 units)

Where Phius comes in: Passive House is allowed on any project, and it is required for residential buildings over 12,000 sq ft in Specialized Code towns. Dominic Zammuto is a Phius Certified Rater and Verifier, so the same team can handle the HERS rating and the Phius verification. Many builders also add ENERGY STAR certification on top of the code HERS rating.

What You Need to Meet the Stretch Code (With Code References)

Beyond the HERS score, these are the items plan reviewers look for on a new home. We flag each one in the report so nothing comes back from plan review. References are to 225 CMR 22 (2025).

Requirement	What it means	Code section
HERS score	At or below the target in the table below, confirmed by a RESNET rater	R406.5, Table R406.5
EV-ready parking	One- and two-family homes and townhouses: at least one 50-amp branch circuit per dwelling for Level 2 charging, labeled "EV READY," ending within 6 ft of the parking space. Other residential buildings: 20% of spaces on a 40-amp, 208/240-volt circuit.	R404.4, Table R404.4
Solar-ready zone	New homes with at least 600 sq ft of roof facing 110° to 270° need a marked solar-ready zone of at least 300 sq ft (150 sq ft for townhouses of 3 stories or less under 2,000 sq ft per unit). Exempt if solar is installed or the zone is shaded more than 70% of daylight hours. In Specialized Code towns this applies to all new buildings, all-electric included.	Appendix RB (RB103), RC103.1
Mixed-fuel homes in Specialized towns	Electric-ready circuits for every gas or oil appliance: a heat pump circuit, a 40-amp range circuit, 30-amp dryer and water heater circuits, and space for a heat pump water heater. Plus on-site solar of at least 4 kW per dwelling, unless the potential solar zone is under 300 sq ft.	RC104.3, RC104.4
Homes over 4,000 sq ft in Specialized towns	Must be all-electric or zero energy (HERS 0 or less)	RC101.2, RC102, RC103
Air tightness and ducts	Blower door test at 3.0 ACH50 or tighter for new homes; duct leakage test on ducted systems	R402.4, R403.3
Ventilation and windows	Mechanical ventilation sized to the home (ERV or HRV common); window U-factor and SHGC as modeled	R403.6, R402
Energy certificate	Permanent certificate posted at or near the electrical panel at the end of the job	R401.3

Worked example of the mechanical ventilation CFM calculation for a 2,700 sq ft four-bedroom home - stretch code report for a building permit in Somerville, MA

Diagram of eligible roof orientation and roof areas for a solar-ready zone - stretch code report for a building permit in Somerville, MA

Diagram comparing an EV-ready parking space with an installed EV charger - stretch code report for a building permit in Somerville, MA

Code text: 225 CMR 22 (residential) · 225 CMR 23 (commercial and multifamily) · Mass.gov Building Energy Code

HERS Targets Your Report Has to Meet

Maximum HERS scores from Table R406.5 of the 2025 Massachusetts Stretch Code. Lower is better.

Project	Mixed-fuel	All-electric
New home	HERS 42	HERS 45
Accessory dwelling unit (ADU)	HERS 52	HERS 55
Addition over 1,000 sq ft or over 100% of the home, major alteration, change of use	HERS 65	HERS 70
Smaller additions and alterations	Usually REScheck or the prescriptive path (inspector decides)

On-site solar and embodied carbon credits can raise some targets a few points. Specialized Code towns add rules for homes over 4,000 sq ft and residential buildings over 12,000 sq ft. Passive House (Phius or PHI) certification is another way to comply.

Massachusetts Table R406.5 maximum HERS scores for new homes, ADUs and major renovations - stretch code report for a building permit in Somerville, MA

Three example houses showing which additions and renovations trigger a HERS rating - stretch code report for a building permit in Somerville, MA

How It Works, Permit to Final

Send your plans

Plans, sections, window specs and equipment choices. We quote the same day.

Projected report

We model the house and send the projected HERS report for your permit application, usually in about one business day.

Fixes before you build

If the score misses the target, we tell you the cheapest changes to get there before anything is ordered.

Pre-drywall inspection

We check insulation and air sealing while it can still be fixed.

Final testing

Blower door and duct leakage tests at the end of the job.

Confirmed certificate

We send the confirmed HERS certificate for your final inspection and certificate of occupancy.

Getting Your Somerville Permit: What the Building Department Needs

Wood-framed new house under construction before insulation - stretch code report for a building permit in Somerville, MA

Diagrams showing when finishing a basement or attic or adding a dormer triggers a HERS rating - stretch code report for a building permit in Somerville, MA

Somerville follows the Specialized (Opt-In) Code, effective July 1, 2023, after following the Stretch Code since January 1, 2012, according to the state's municipal energy code adoption list.

Building permits in Somerville go through the Inspectional Services Division, and applications are filed online through the city's Citizenserve portal. For a new home or a large addition, upload the projected HERS report with the permit application so the energy review moves with plan review instead of holding it up.

Because Somerville is a Specialized Code community, new homes over 4,000 sq ft must be all-electric or zero energy, and residential buildings over 12,000 sq ft must meet Passive House. Mixed-fuel homes also need electric-ready circuits and, unless the roof is too small or shaded, at least 4 kW of on-site solar. We confirm which of these applies before we run the numbers.

Somerville projects are covered from our Somerville office at 519 Broadway. We also have a Somerville stretch code help page and a Somerville HERS rating page with more local detail.

Permit Reports in Nearby Towns

Same report, same process, local building department details:

All of Massachusetts Boston Cambridge Newton Wellesley Brookline Lexington Arlington

Permit Report FAQ for Somerville

What is a stretch code report for a building permit?

It is a projected HERS rating: a RESNET-certified HERS rater models your plans and shows the house will meet the Massachusetts Stretch Code (or Specialized Code) HERS target. Building departments may call it a stretch code report, energy report, HERS report or energy compliance report. It is filed with your building permit application.

Is a stretch code report the same thing as a HERS rating?

Yes. At permit it is the projected (plan-based) HERS rating. At the end of the job the same rater tests the house and issues the confirmed HERS rating, which the building inspector needs before final sign-off.

How fast can I get the report for my permit?

Send the plans, the heating, cooling and hot water choices (gas or electric, ducted or mini-split) and the window specs. Once the quote is accepted, the projected report is usually ready in about one business day.

Do I need a HERS report for an addition or renovation?

Under the Stretch Code, additions over 1,000 sq ft or more than 100% of the existing home need a HERS rating (HERS 65 mixed-fuel, HERS 70 all-electric). Smaller additions and alterations can usually use REScheck or the prescriptive path. The building inspector has the final say on which path applies.

Who is allowed to prepare the report?

The code uses the RESNET HERS Index, so the rating must come from a RESNET-certified HERS rater and is verified by an approved third party. Home Energy Efficiency Consultants is a RESNET-certified HERS rater (RESNET ID 3385643).

What happens after the permit is issued?

We come out twice: once before drywall to inspect insulation and air sealing, and once at the end for the blower door and duct leakage tests. Then we send the confirmed HERS certificate for the final inspection.

What are the EV-ready requirements for a new home?

Under R404.4, one- and two-family homes and townhouses need at least one 50-amp branch circuit per dwelling for Level 2 charging, labeled "EV READY" and ending within 6 ft of the parking space. Other residential buildings need 20% of parking spaces on a 40-amp, 208/240-volt circuit.

Does an all-electric home need a solar-ready zone?

Usually yes. Appendix RB applies to new homes with at least 600 sq ft of roof facing 110 to 270 degrees, and the solar-ready zone must be at least 300 sq ft. It is exempt if solar is installed or the zone is shaded more than 70% of daylight hours. In Specialized Code towns, RC103.1 applies it to all new buildings, all-electric included.

Do commercial buildings need a blower door test?

Yes. Under 225 CMR 23 the building envelope is tested for air leakage, with a limit of 0.35 cfm per sq ft at 75 Pa (C402.5.2). Commercial buildings up to 20,000 sq ft can usually show compliance with COMcheck; larger ones need energy modeling or Passive House.

When is Phius (Passive House) required?

Passive House is allowed on any project. In Specialized Code towns it is required for residential buildings over 12,000 sq ft of conditioned floor area. In Stretch Code towns, multifamily buildings over 12,000 sq ft can use Passive House, a HERS rating or TEDI energy modeling.

Is Somerville on the Stretch Code or the Specialized Code?

Somerville uses the Specialized (Opt-In) Code, effective July 1, 2023, after following the Stretch Code since January 1, 2012 (state adoption list). The Stretch Code HERS targets apply, plus the Specialized rules for new homes over 4,000 sq ft and multifamily buildings over 12,000 sq ft.

Where do I file my building permit in Somerville?

Building permits in Somerville go through the Inspectional Services Division, filed online through the city's Citizenserve portal. Attach the projected HERS report when you apply so the energy review runs with plan review.

Need a Stretch Code Report for Your Somerville Permit?

Send your plans today. Most projected HERS reports are ready in about one business day after the quote is accepted.

Get My Permit Report Call 617-501-6788

68 South St - Framingham MA

Energyconsultants01@gmail.com

+1 (617) 501-6788