Residential

OverviewRooftop PV at volumeRoof & dronePlanes measured on the roofAttic & structureRafters recordedElectricalPanel and interconnectionDesign & engineeringModel to stamped set

Commercial & Industrial

OverviewBig roofs, real structureOn-site surveyRoof, structure, switchgearDesign & engineeringPE stampedVisual inspectionModule resolutionThermal inspectionFaults as heatElectroluminescenceCell-level cracks

Utility-Scale

OverviewThousands of acresLiDAR topographyTerrain before earthworkLand surveyingBoundary and topographicConstruction monitoringProgress, measuredThermal & ELEvery string

Across every scale

Site surveysRoof and electrical, one visitPermitting & engineeringStamped plan setsInspectionAerial thermal and ELShading analysisSA, TOF and TSRFSurvey locationsState and metro guides

The platform

Platform overviewPortal, 3D models, live dataShading analysisMove the sun yourselfCost calculatorWhat bad field data costs you

Sign in

Vanguard AccessInvite only · survey data portalScheduling & DispatchCrewLink · all verticals

Field Notes · build vs. buy

What a survey really costsPart 01 · the full modelUtilization is the whole gamePart 02 · a real TuesdayThe break-even headcountWhen hiring pays offTwo technicians, two roofsVariance, measuredThe hybrid crewIn-house plus outsourced

Field Notes · reference

Site survey checklistBuilt backwards from reworkHow long a survey takesHour by hourDo panels need a permit?What goes in the packageStorage site surveysThe capture listCompare survey vendorsQuestions to ask any vendor

Company

All servicesAll Field NotesAboutBook a 15-min call

Home  /  Solar site surveys  /  Connecticut

Solar site surveys · Connecticut

Solar site surveys in Connecticut

A technician on the roof, in the attic and at the service panel, with the survey read against the code editions, AHJs and utilities that apply in Connecticut.

NEC 2020Electrical code in effect
2Utilities covered here
48 hrsSurvey to deliverable
Nationwide500+ technicians
Short answer

Connecticut enforces one statewide code: the 2022 Connecticut State Building Code (2021 IRC and 2020 NEC) and the 2022 Fire Safety Code (2021 IFC), because the 2026 codes are still awaiting legislative approval. Each town's building official issues permits, and a state amendment to IRC R324.6 lets arrays skip eave-to-ridge pathways on a slope when the opposite slope is clear. Eversource and UI compensate new rooftop solar through the RRES program, which Public Act 26-127 extends through 2035.

What changes in Connecticut

The capture spec is the same everywhere. What the engineer and the plan reviewer read it against is not.

CT · METROSHartford
Code stack
2020NEC 2020National Electrical Code · effective Oct 1, 2022. The 2022 Connecticut State Building Code adopts the 2020 NEC with state amendments for permits applied for on or after October 1, 2022. The 2026 code would move to the 2023 NEC, but its planned July 1, 2026 start was delayed while the Legislative Regulation Review Committee considers it.1,2
2021IRC 2021The residential portion of the 2022 State Building Code is the 2021 IRC with Connecticut amendments, including its own rooftop PV access rules. The pending 2026 code is based on the 2024 IRC.1,2
2021IFC 2021The 2022 Connecticut State Fire Safety Code adopts the 2021 IFC. The separate State Fire Prevention Code, used for existing buildings, is based on NFPA 1 (2021) and deletes that code's general PV section, keeping only rules for ground-mounted arrays.3,4
Rooftop fire access. Connecticut's amended IRC R324.6 requires two 36-inch eave-to-ridge pathways on separate roof planes (one on the street or driveway side), but drops the pathway on the array's slope when the array sits on only one slope of a ridge, hip or valley and the opposite slope is clear with a roof access point. Ridge setbacks are 18 inches when arrays cover 33% or less of the roof area and 36 inches above that, and roofs of 2:12 or flatter are exempt.1,5

Climate and site factors

Snow

Connecticut's building code lists ground snow loads by town, for example 30 psf in Hartford, Danbury and Darien, 35 psf in Avon and New Hartford, and 40 psf in Cornwall in the northwest hills.1

Wind

The same town table sets design wind speeds and flags which towns are in the hurricane-prone region; Hartford's residential ultimate design wind speed is 120 mph.1

Roof access

Placing the array on one slope and leaving the opposite slope clear with a ladder point can remove the need for a pathway on the solar slope under Connecticut's R324.6 amendment.1

HOAs and condos

Detached homes in condominiums and planned communities gained rooftop solar protections on January 1, 2026, but associations may still opt out by January 1, 2028, so check the association's status.6

Permitting in Connecticut

Who reviews the plan set, and what the state layers on top.

Utilities and interconnection

The utility decides the interconnection path and what an exported kilowatt-hour is worth.

Eversource Energy Eversource

Connecticut's largest electric utility, serving about 149 cities and towns including Hartford. It posts its application to connect, net metering information, and hosting capacity maps on its Connecticut interconnection page.11,12

Interconnection page ↗

United Illuminating UI

Serves 17 towns and cities in the greater New Haven and Bridgeport areas and administers RRES tariffs for its customers alongside Eversource.13,14

Interconnection page ↗
Export compensation. Rooftop systems up to 25 kW AC enroll in PURA's Residential Renewable Energy Solutions program, launched January 2022, choosing a Buy-All tariff or a Netting tariff; under Netting, monthly net excess is credited at the customer's retail rate as bill credits that carry forward, plus a production-based REC payment. Public Act 26-127 extends the programs through 2035 with successor tariffs from January 1, 2028, as of September 2026.15,14,8,10

What we capture on every Connecticut survey

One standard, one visit, the same record in Connecticut as everywhere else. What it gets checked against is the code stack above.

Roof and structure

  • Measured roof planes: pitch, azimuth, dimensions
  • Every penetration and obstruction, located
  • Rafter or truss size, spacing and span
  • Decking type and condition
  • Layer count at a cut edge
  • Setbacks and fire pathway constraints
  • Horizon shading capture per array area

Electrical and interconnection

  • Main breaker and bus bar rating, photographed separately
  • Meter location and configuration
  • Slot count: used, open, tandem, double-tapped
  • Available interconnection points
  • Existing loads and sub-panels
  • Conduit route, measured along the actual path
  • Grounding electrode and bonding path

Commercial buildings

  • Membrane type, age and condition, with drainage pattern
  • Bar joist depth, spacing and span
  • Deck type and gauge
  • Switchgear and available bus capacity
  • Access and lift constraints for the install crew

Every visit

  • Roof and electrical in one visit, no second trip
  • 48-hour turnaround from survey to deliverable
  • Photo documentation throughout
  • Permit sets available, stamped, 6 days from survey

Connecticut solar survey FAQ

Which NEC edition applies to solar in Connecticut?

The 2020 NEC, as part of the 2022 Connecticut State Building Code. The 2026 code would adopt the 2023 NEC, but as of September 2026 it still awaits approval by the Legislative Regulation Review Committee.1,2

What replaced net metering in Connecticut?

The Residential Renewable Energy Solutions program, run by Eversource and UI since January 2022, which offers a Buy-All tariff or a Netting tariff for systems up to 25 kW AC.15,14

Is RRES ending in Connecticut?

No. Public Act 26-127 reauthorizes the residential program through 2035, with PURA-designed successor tariffs starting January 1, 2028; storage-paired systems are exempt from new caps on rooftop solar.10,9

Can a Connecticut HOA block rooftop solar?

Since January 1, 2026, condominium and planned community rules cannot prohibit or unreasonably restrict rooftop solar on single-family detached units, though associations may opt out of the law by January 1, 2028.6

What ridge setback applies to solar in Connecticut?

18 inches on each side of a horizontal ridge when arrays cover 33% or less of the roof's plan area, and 36 inches above that, under the 2022 code; a proposed change would allow 12 inches in some one-slope cases.5

Services and further reading

Metro pages for Connecticut: Hartford.

From Field Notes

Sources

Every local fact on this page links to where it came from. Codes, programs and tariffs change: confirm the current requirement with the AHJ and the utility before you design.

  1. https://portal.ct.gov/das/-/media/das/office-of-state-building-inspector/2022-state-codes/2022-csbc-final.pdf
  2. https://portal.ct.gov/das/office-of-state-building-inspector/building-and-fire-code-adoption-process
  3. https://portal.ct.gov/-/media/das/office-of-state-building-inspector/2022-state-codes/2022-csfsc-final.pdf
  4. https://portal.ct.gov/-/media/DAS/Office-of-State-Building-Inspector/2022-State-Codes/2022-CSFPC-Final.pdf
  5. https://portal.ct.gov/das/-/media/das/office-of-state-building-inspector/codes-and-standards/2024/2025-ccp/ccp25-056-bc-irc-r32462--mike-trahan.pdf?rev=b869a2377cdd4a599c0dbbc54bb4fbeb&hash=597259B678644B216297B158B7C33534
  6. https://cga.ct.gov/2025/SUM/PDF/2025SUM00073-R02HB-06957-SUM.PDF
  7. https://www.cga.ct.gov/current/pub/chap_541.htm
  8. https://www.cga.ct.gov/2026/BA/PDF/2026HB-05340-R01-BA.PDF
  9. https://pv-magazine-usa.com/2026/06/05/connecticut-governor-signs-the-states-omnibus-2026-solar-bill/
  10. https://portal.ct.gov/deep/news-releases/news-releases---2026/governor-lamont-signs-legislation-making-renewable-energy-more-affordable-and-easier-to-access
  11. https://www.eversource.com/residential/about/doing-business-with-us/interconnections/connecticut
  12. https://en.wikipedia.org/wiki/Connecticut_Light_and_Power_Company
  13. https://en.wikipedia.org/wiki/United_Illuminating
  14. https://portal.ct.gov/-/media/PURA/Residential-Renewable-Energy-Solutions-Program-Manual.pdf
  15. https://portal.ct.gov/pura/electric/office-of-technical-and-regulatory-analysis/clean-energy-programs/residential-renewable-energy-solutions-program

Researched September 30, 2026.

Talk through your next Connecticut site in 15 minutes

Bring your monthly job count and the AHJs you submit into, and we will tell you straight whether we fit.

Book a 15-min call
Book a 15-min call