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  /  South Carolina  /  Charleston

Solar site surveys · Charleston, SC

Solar site surveys in Charleston

Roof, attic and service panel captured in one visit, with the plan set built for the Charleston AHJ you submit into and the utility that serves the address.

NEC 2020Electrical code in effect
3AHJs covered here
48 hrsSurvey to deliverable
Nationwide500+ technicians
Short answer

The City of Charleston issues a residential solar building permit with an electrical sub-permit, and wants a sealed South Carolina structural letter, a roof plan with access pathways, a single-line diagram, and Board of Architectural Review approval in historic districts. Unincorporated areas go to Charleston County, which asks for structural, wind and seismic design analysis. Design loads are 150 mph wind and Seismic Design Category D2.

What changes in Charleston

South Carolina state rules apply here, plus whatever the local AHJ amends.

SC · CHARLESTONCharleston
Code stack
2020NEC 2020National Electrical Code · effective Jan 1, 2023. The Building Codes Council adopted the 2020 NEC with SC modifications on October 6, 2021, for enforcement by all municipalities and counties from January 1, 2023. The Council adopted the 2023 NEC with the 2024 code set on August 26, 2025, with local implementation on January 1, 2027.1,2,3
2021IRC 2021The 2021 South Carolina Residential Code (2021 IRC with SC modifications) applies until the 2024 IRC takes over on January 1, 2027. Neither modification list includes a change to the IRC's solar section R324, and local governments cannot enforce modifications the Council has not approved.1,3,4
2021IFC 2021The 2021 South Carolina Fire Code is the 2021 IFC with SC modifications; the 2024 IFC with modifications published in the State Register on May 22, 2026 follows on January 1, 2027.1,5
Rooftop fire access. Because South Carolina adopts the IRC without modifying R324, the model code's residential pathway and ridge setback rules apply as written, and the IFC's PV provisions cover other buildings. Charleston's residential solar guidance asks for a roof plan showing array locations with roof access and pathways.4,3,6

Climate and site factors

Hurricane wind

City design criteria set a 150 mph design wind speed with wind-borne debris zone 2, which governs attachment count and uplift on every array.7

Seismic

Charleston is Seismic Design Category D2, and the county's solar checklist explicitly asks for seismic as well as wind analysis.7,8

Historic roofs

On historic buildings the BAR prefers rear slopes or accessory buildings, low-profile reversible mounting, painted conduit, and structural confirmation of load, wind load and uplift by a qualified engineer.9

Flood maps

The city sits on both Charleston County (effective January 29, 2021) and Berkeley County (December 17, 2018) flood maps, which matters for ground-level equipment on low sites.7

Permitting in Charleston

The main AHJs, and how the rest of the metro splits up.

City of Charleston Permit Center

Residential solar is a Solar Panel permit with a separate electrical sub-permit. Applications need building and electrical permit forms, a roof plan showing array locations and access pathways, a structural letter or plan sealed by an SC design professional, a single-line diagram and array specs, and a BAR application in historic districts. Inspections are electrical rough, electrical final and building final.6,10

Official page ↗

City of Charleston Board of Architectural Review

In the Old and Historic District, Old City District, Landmark Overlay and Historic Corridor District, panels on Category 1 or 2 buildings must not be visible from the public right of way, and panels should stay low profile (no more than 8 inches above the roof), reversible, and avoid penetrating historic roofing where possible.9

Official page ↗

Charleston County Building Inspection Services

For unincorporated areas the county asks for a structural analysis of the existing roof, wind and seismic design, a panel layout with clearances, fastening design and an electrical layout, with values for both building and electrical permits. Its residential solar form notes the county does not perform plan review on these submittals, and all work remains subject to field inspection.8,11

Official page ↗

Across the metro

Each municipality enforces the same Council-adopted codes through its own permit office, and Charleston County handles unincorporated areas; the City of Charleston itself spans both Charleston and Berkeley counties.1,7,12

South Carolina-wide rules that still apply

Utilities and interconnection

Check the customer's bill for the serving utility: DESC's Solar Choice rider and Santee Cooper's DG-25 rider treat exports very differently, from TOU-period netting with a November cash-out to hourly netting at 4.15 cents per kWh.15,16

Dominion Energy South Carolina DESC

Customers who applied on or after June 1, 2021 take the Solar Choice rider on Rate 5 time-of-use service, up to 20 kW AC. Installers use PowerClerk and the SC Generator Interconnection Procedures.17,15

Interconnection page ↗

Santee Cooper

The state-owned utility's Distributed Generation Rider DG-25 allows residential systems up to the lesser of 20 kW or the customer's estimated maximum monthly demand, requires an interconnection application and fee, and adds a standby charge.16,18

Interconnection page ↗
Export compensation. DESC Solar Choice (tariff effective July 2026) nets exports against usage within each time-of-use period, carries excess kWh forward, and pays any balance at avoided cost on the November bill, with a $13.50 minimum bill. Duke's Rider RSC (effective January 1, 2026) nets within each TOU period monthly and credits net excess at $0.0419 per kWh. Santee Cooper nets hourly and credits returned energy at $0.0415 per kWh with a $10 customer charge.15,19,16,18

What we capture on every Charleston survey

The same capture standard as every other South Carolina job, so the plan set is built on what the technician verified on site.

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

Charleston solar survey FAQ

What does the City of Charleston need for a residential solar permit?

A Solar Panel permit with an electrical sub-permit, a roof plan showing arrays and access pathways, a structural letter sealed by an SC design professional, a single-line diagram with array specs, and a BAR application if the house is in a historic district.6

What wind speed do Charleston solar arrays have to meet?

The City of Charleston's design criteria list a 150 mph design wind speed, with the city in wind-borne debris zone 2.7

Can solar go on a historic house in downtown Charleston?

Often, but with BAR review: on Category 1 or 2 buildings panels must not be visible from the public right of way, and all installations should be low profile and reversible.9

Does Charleston County review solar plans for unincorporated areas?

The county's residential solar form says it does not perform plan review on these submittals; the applicant certifies an engineer has approved the structure, and field inspections still apply.11

Who can install the racking on a Charleston roof?

Not a solar panel installer alone: the city's guidance limits that license to panels and electrical work, so roof mounting or framing needs a residential builder, a specialty roofer or a general contractor with a roofing classification.6

Services and further reading

State-level detail is on the South Carolina page; every location is on the solar site survey hub.

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://www.llr.sc.gov/bcc/pdffiles/SC-Code-Adoption-Notice.pdf
  2. https://llr.sc.gov/bcc/BCAdoption.aspx
  3. https://llr.sc.gov/bcc/PDFfiles/2024%20Final%20Modification%20Index%20with%20Hyperlinks.pdf
  4. https://llr.sc.gov/bcc/PDFfiles/2021-Modification-index.pdf
  5. https://llr.sc.gov/bcc/PDFfiles/State%20Register%20-%20May%2022,%202026.pdf
  6. https://www.charleston-sc.gov/DocumentCenter/View/39974
  7. https://www.charleston-sc.gov/DocumentCenter/View/18835
  8. https://www.charlestoncounty.gov/departments/building-inspection-services/forms/Solar-Panel-Requirements-for-Permits.pdf?v=735
  9. https://www.charleston-sc.gov/DocumentCenter/View/30884
  10. https://www.charleston-sc.gov/856/Permit-Center
  11. https://www.charlestoncounty.gov/departments/building-inspection-services/forms/Residential-Solar-Panel-Information-Form.pdf?v=735
  12. https://www.charlestoncounty.gov/departments/building-inspection-services/forms.php
  13. https://www.scstatehouse.gov/code/t58c040.php
  14. https://www.scstatehouse.gov/code/t27c030.php
  15. https://www.dominionenergy.com/-/media/content/rates-and-tariffs/pdfs/south-carolina/electric/riders/rider-to-residential-rate5-solar-choice.pdf
  16. https://www.santeecooper.com/programs-incentives/empowersolar/
  17. https://www.dominionenergy.com/south-carolina/save-energy/solar-technical-resources
  18. https://www.santeecooper.com/Rates/_pdfs/Adjustments/DG-25.pdf
  19. https://p-cd.duke-energy.com/-/media/pdfs/for-your-home/rates/electric-sc/scriderrsc.pdf?rev=ff56b1004c78460dbe599d628a149982

Researched September 30, 2026.

Talk through your next Charleston 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