Bolthole Index

Spartanburg County, South Carolina

Building permits, zoning and septic rules in Town of Duncan, SC

Town of Duncan, South Carolina has municipal zoning, and campground or RV-park construction needs building permits and inspections from Spartanburg County Building Codes.123 Start an ordinary home project with Duncan Planning & Zoning to confirm the town approval and building-permit route.4 Septic approval comes separately from the South Carolina Department of Environmental Services when public or community sewer does not serve the property.56 RV living on a residential lot is prohibited.7

At a glance

Building permits
County Building Codes permits and inspects campground and RV-park construction; ask Duncan about the ordinary-home route234
Zoning
Town zoning applies inside Duncan; start with Duncan Planning & Zoning14
Septic permits
SCDES approval required where public or community sewer does not serve the property6
RV living
No living, sleeping or housekeeping in an RV on a residential lot7
Tiny houses
Planned tiny-home neighborhoods, with 10–40 houses on at least 5 usable acres8
Owner-builder
State exemption is conditional; building codes and zoning still apply9
Private wells
Notice of Intent for state General Permit coverage before residential-well construction10

Who to call

Zoning

Town of Duncan Planning & Zoning

Town planning and zoning questions; confirmation of the building-permit route for an ordinary home inside town limits

864.439.1877

153 West Main Street, Duncan, SC 29334

Building permits

Spartanburg County Building Codes Department

Building permits and inspections for campground and RV-park construction in Duncan, as specified by the town code; confirm other municipal work with Duncan first

864-596-2727

366 N Church St Main Level, Suite 500 Spartanburg SC 29303

Septic permits

South Carolina Department of Environmental Services — Onsite Wastewater

Septic application questions before submission; state septic permitting is separate from town zoning and building approvals

1-855-731-2504

[email protected]

Contact details are copied from each office’s official page and were checked against it on October 11, 2026.

Off-grid gear

Going off-grid in Town of Duncan means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Town of Duncan, SC?

Duncan expressly requires Spartanburg County Building Codes to permit and inspect all structures and construction associated with campgrounds or recreational vehicle parks inside town limits.23 That requirement is specific to those developments; for an ordinary home, ask Duncan Planning & Zoning to identify the building-permit authority and town approvals before submitting construction plans.4

South Carolina requires municipal building-code administration, but allows municipalities to arrange building-code services through agreements with other government entities.11 A qualifying owner-builder exemption concerns residential-builder licensing and still requires compliance with applicable building codes, laws and zoning regulations.9

Who handles building permits and zoning in Town of Duncan?

Duncan Planning & Zoning is the starting point for a town zoning or planning issue; call 864.439.1877 and describe the proposed use and property.4 Duncan has a zoning appeals board for appeals of zoning decisions.4 For campground and RV-park construction in Duncan, the named building-permit and inspection authority is Spartanburg County Building Codes, reachable at 864-596-2727.2312

Keep wastewater approval separate: SCDES administers individual septic systems statewide.5 Before submitting a septic application, questions about the application process or permit modifications go to 1-855-731-2504 or [email protected].13

Does Town of Duncan have zoning, lot-size and setback rules?

Duncan has town zoning that applies within the incorporated area; county rules for unincorporated land should not be used as Duncan parcel standards.114 Ask Duncan Planning & Zoning to confirm the parcel district and the standards for the proposed house, accessory building or manufactured home.4 We could not confirm a complete ordinary-residential schedule for minimum dwelling size, setbacks, lot coverage or building height; ask Duncan Planning & Zoning for those standards before choosing a building footprint.4

The confirmed tiny-home-neighborhood minimum lot area is 1,950 square feet where public sewer is available; that is a special development standard, not a townwide lot-size rule.15 Manufactured homes brought into or relocated within Duncan must meet the town’s manufactured-home standards and applicable floodplain standards.16

How do septic permits and private wells work in Town of Duncan?

A home or manufactured home in Duncan that is not served by public or community sewer needs SCDES approval and a permit to install a septic system first.6 Public-sewer accessibility must be verified before applying, because an onsite wastewater permit cannot be issued where public sewer is accessible.17 SCDES evaluates a new-home site before issuing the septic construction permit, and the installer must arrange the final inspection before covering the system.18

A composting or incinerating toilet is not an automatic sanitation exemption: qualifying nonwater-carried systems require engineering plans, a state permit to construct and approval to operate.19 If pressurized water generates gray water, a separately permitted onsite gray-water system is required.20 Individual residential wells require a Notice of Intent for General Permit coverage before construction; the residential-well fee is $70.10

Can you live in an RV or tiny house in Town of Duncan?

Duncan prohibits using major recreational equipment for living, sleeping or housekeeping when parked or stored on a residential lot, so an RV is not a lawful residential-lot fallback while building a home.7 The loading-and-unloading allowance is limited to 24 hours; it does not authorize residential occupancy.7 Duncan campground and RV-park rules require at least 5 contiguous usable acres and limit density to 12 units per physical acre.21 Utility buildings cannot be used for occupancy under the town’s campground and RV-park construction rules.22

Duncan permits tiny houses in planned residential developments with individually owned fee-simple lots in a tiny-home-neighborhood setting; developments must contain 10–40 houses on at least 5 usable acres.8 Those rules exclude RVs, park models, campers and seasonal-use designs, and impose additional setback, parking, open-space and road standards.8 Tiny-house development lots cannot directly access an existing public street or highway and must have at least 20 feet of access/frontage on approved access, a private road or a private drive.23

Building a home in Town of Duncan: what are the steps?

  1. Start with Duncan Planning & Zoning: identify the parcel, proposed dwelling type and use, then request the applicable district standards and building-permit route.4
  2. Verify public-sewer accessibility before commissioning a septic proposal; where public or community sewer does not serve the property, obtain SCDES septic approval first.176
  3. Ask Duncan about floodplain status before settling the house design: covered residential construction in special flood-hazard areas must place the lowest floor at or above base flood elevation, and residential basements are prohibited.24
  4. If acting as your own builder, follow the state exemption’s personal-supervision, permit-signature and recorded-notice requirements, while complying with building codes and zoning.9
  5. Arrange the septic final inspection before covering the system.18

For land outside Duncan town limits, use the Spartanburg County guide for the county’s unincorporated-area building-permit and land-use answers.2526

Watch-outs

  • Duncan’s residential-lot RV prohibition means the loading-and-unloading allowance cannot be used as permission to live in an RV while building.7
  • We could not confirm Duncan’s current building-permit fee amounts or ordinary-home certificate-of-occupancy procedure; ask Duncan Planning & Zoning to identify the responsible office before budgeting and scheduling move-in.4
  • South Carolina’s newly adopted mandatory code editions have an implementation date of January 1, 2027; ask the building authority which edition applies to the proposed construction schedule.27
  • The state farm-structure exemption excludes residences and attached structures, requires an affidavit before construction, and preserves local building-permit authority and applicable flood standards.28

Sources

  1. Duncan Code § 125-748, Purpose and authority (Town of Duncan), quoted and re-checked
  2. Duncan Code § 125-750, Campground and recreational vehicle park requirements (Town of Duncan), quoted and re-checked
  3. Duncan Code § 125-750, Campground and recreational vehicle park requirements (Town of Duncan), quoted and re-checked
  4. Town of Duncan Planning & Zoning (townofduncansc.com)
  5. Septic Tanks - Residential, Single Home Builder (South Carolina statewide rule), quoted and re-checked
  6. Septic Tanks - Residential, Single Home Builder (South Carolina statewide rule), quoted and re-checked
  7. Duncan Code § 125-8, Supplementary regulations (Town of Duncan), quoted and re-checked
  8. Duncan Code § 125-760, Tiny home neighborhood (Town of Duncan), quoted and re-checked
  9. South Carolina Code Title 40, Chapter 59 — Residential Home Builders (South Carolina statewide rule), quoted and re-checked
  10. Private Drinking Water Wells (South Carolina statewide rule), quoted and re-checked
  11. South Carolina Code Title 6, Chapter 9 — Building Codes (South Carolina statewide rule), quoted and re-checked
  12. Spartanburg County Building Codes Department (spartanburgcounty.gov)
  13. South Carolina Department of Environmental Services — Onsite Wastewater (des.sc.gov)
  14. South Carolina Code Title 6, Chapter 29 — Local Government Comprehensive Planning Enabling Act (South Carolina statewide rule), quoted and re-checked
  15. Duncan Code § 125-760, Tiny home neighborhood (Town of Duncan), quoted and re-checked
  16. Duncan Code § 125-8, Supplementary regulations (Town of Duncan), quoted and re-checked
  17. Professional Soil Classifiers - Sewer Accessibility Verification (South Carolina statewide rule), quoted and re-checked
  18. Septic Tanks - Frequently Asked Questions (South Carolina statewide rule), quoted and re-checked
  19. South Carolina State Register Vol. 45, Issue 5 — Regulation 61-56 (South Carolina statewide rule), quoted and re-checked
  20. South Carolina State Register Vol. 45, Issue 5 — Regulation 61-56 (South Carolina statewide rule), quoted and re-checked
  21. Duncan Code § 125-749, Definitions (Town of Duncan), quoted and re-checked
  22. Duncan Code § 125-750, Campground and recreational vehicle park requirements (Town of Duncan), quoted and re-checked
  23. Duncan Code § 125-760, Tiny home neighborhood (Town of Duncan), quoted and re-checked
  24. Duncan Code § 109-80, Specific flood-hazard standards (Town of Duncan), quoted and re-checked
  25. Article 1 — Applications and Required Permits (2026 county census)
  26. Zoning in Spartanburg County (2026 county census)
  27. 2024 Building Code Modification Index (South Carolina statewide rule), quoted and re-checked
  28. South Carolina Code of Laws, Section 6-9-65 (South Carolina statewide rule), quoted and re-checked

Written October 11, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

Answers from the rulebook for Town of Duncan

Town of Duncan’s own rules

  • Building permitRequired

    Structures and construction associated with campgrounds or recreational vehicle parks inside Duncan town limits.

    • The requirement is specific to campground and RV-park construction.
    • The Spartanburg County Building Codes Department is the named permitting body.
    “All structures and construction associated with campgrounds or recreational vehicle parks must be permitted and inspected by the Spartanburg County Building Codes Department.”
  • Building code adoptedPartial

    Building-code requirements for RVs, campgrounds, and related structures inside Duncan town limits.

    • RV construction must comply with the residential building code or NFPA 1192.
    • Utility buildings are not constructed to either standard and are not permitted for occupancy.
    • The supplied excerpts do not identify the complete adopted code editions.
    “RV's must be built to the residential building code or the NFPA 1192 Recreational Vehicle construction standard. Utility buildings are not constructed to either standard and are not permitted for occupancy.”
  • InspectionsRequired

    Structures and construction associated with campgrounds or recreational vehicle parks inside Duncan town limits.

    • Inspection is assigned to Spartanburg County Building Codes Department.
    “All structures and construction associated with campgrounds or recreational vehicle parks must be permitted and inspected by the Spartanburg County Building Codes Department.”
  • Local zoningPresent

    Zoning and land-use regulation inside the incorporated areas of Duncan town.

    • The cited subdivision is specifically for campgrounds and recreational vehicle parks; the complete zoning code remains broader than this excerpt.
    “These regulations shall apply to the incorporated areas in the Town of Duncan. However, where sections conflict or overlap, whichever imposes the most stringent restrictions shall prevail.”
  • Zoning districtsPartial

    Zoning districts and special district regulations inside Duncan town limits.

    • The opened excerpts identify the MHP Mobile Home Park/Campground and Recreational Vehicle Parks/Tiny Home Communities subdivision and reference RM-8, RM-16, MHP, NBD, CBD, GBD, RLI, and GI districts.
    • The complete district list and dimensional tables were not opened.
    “In all front yards in the RM-8, RM-16, MHP, NBD, CBD, GBD, RLI, and GI districts, a planting strip not less than six feet wide shall be provided along the street line on the property”
  • Minimum lot sizeSpecified

    Tiny-home neighborhood lots in zoned areas inside Duncan town limits.

    • Applies where public sewer is available.
    • Other tiny-home-neighborhood zoning and development requirements apply.

    minimum lot area: >= 1950 square feet (Where public sewer is available.)

    “Where public sewer is available, the minimum area lot size shall be 1,950 square feet.”
  • Living in an RVLimited

    Recreational vehicles on residential lots and in RV parks inside Duncan town limits.

    • Major recreational equipment may be parked on residential premises for no more than 24 hours during loading or unloading.
    • It may not be used for living, sleeping, or housekeeping on a residential lot.
    • RV parks require permits issued by Spartanburg County and Duncan.
    • Uninhabitable RVs may not be placed, parked, or stored in town RV parks.
    • RVs must have current registration tags.

    maximum loading/unloading period: <= 24 hours (During loading or unloading.)

    “No such equipment shall be used for living, sleeping, or housekeeping purposes when parked or stored on a residential lot. No such equipment shall be parked in any location not approved for such use.”
  • Camping on your landLimited

    Camping and campground/RV-park uses inside Duncan town limits.

    • Tent camping is prohibited.
    • An RV park/campground requires at least five contiguous usable acres.
    • The maximum density is 12 units per physical acre.
    • Covered parks require town and county permitting and applicable land-disturbance permits.

    minimum acreage: >= 5 contiguous usable acres · maximum density: <= 12 units per physical acre

    “Camping unit means a portable structure, shelter, or vehicle (other than a tent, tent camping is prohibited) designed and intended for occupancy by persons engaged in RVing or camping.”
  • Tiny homesLimited

    Tiny houses in planned residential developments/tiny-home neighborhoods inside Duncan town limits.

    • Tiny houses are permitted only in a planned residential development in a tiny-home-neighborhood setting with individually owned fee-simple lots in zoned areas.
    • The development must contain 10 to 40 tiny houses on at least five usable acres.
    • The rules exclude RVs, park models, campers, and other seasonal-use designs regulated by RVIA.
    • Additional lot, setback, parking, open-space, screening, lighting, and road standards apply.

    minimum units: >= 10 houses · maximum units: <= 40 houses · minimum development area: >= 5 usable acres · minimum lot area with public sewer: >= 1950 square feet (Where public sewer is available.)

    “Tiny houses are permitted within a planned residential development in a tiny home neighborhood setting with individually owned (fee simple) lots in zoned areas. Tiny house subdivisions in the zoned areas shall follow the guidelines and requirements of the Zoning Ordinance.”
  • Manufactured homesLimited

    Manufactured homes brought into or relocated within Duncan town limits.

    • Manufactured homes must comply with the standards in Duncan Code § 125-8(o) and applicable floodplain standards.
    • The supplied § 125-8 excerpt is truncated before all standards and exceptions.
    “All manufactured homes brought into the town or relocated within the town subsequent to the adoption of this chapter, whether placed in a mobile home park or on an individual parcel inside a mobile home subdivision, shall be required to be in compliance with each of the following requirements:”
  • Driveway accessRequired

    Tiny-house development lots inside Duncan town limits.

    • No lot may directly access an existing public street or highway.
    • Each lot must have at least 20 feet of access/frontage on an approved access, private road, or private drive.
    • Private drives require a 20-foot improved surface and drainage.
    • Public roads, sidewalks, and rights-of-way may not be used for parking or maneuvering.

    minimum access/frontage: >= 20 feet · private-drive improved surface width: 20 feet

    “No lot shall have direct access to an existing public street or highway. All lots shall have a minimum of 20 feet of access to and frontage on an approved access to a public street or on a private road constructed to current road standards or private drive.”
  • Building in a floodplainLimited

    New construction and substantial improvements in areas of special flood hazard inside Duncan town limits.

    • Applies in Zones A, AE, AH, AO, A1-30, V, and VE where base-flood-elevation data has been provided.
    • Residential construction must have the lowest floor at least 0 feet above base flood elevation.
    • No basements are permitted for residential construction.
    • Additional standards apply to non-residential and manufactured-home construction.

    minimum elevation above base flood elevation: >= 0 feet (Where base flood elevation data has been provided.)

    “New construction or substantial improvement of any residential structure (including manufactured homes) shall have the lowest floor elevated no lower than 0 feet above the base flood elevation.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Town of Duncan or Spartanburg County directly.

  • Owner-builder exemption — Owner-builder exemptions inside Duncan town limits.
  • Certificate of occupancy — General certificates of occupancy inside Duncan town limits.
  • Minimum dwelling size — Residential districts inside Duncan town limits.
  • Lot coverage — Lots inside Duncan town limits.
  • Building height — Buildings inside Duncan town limits.
6 more unanswered
  • Accessory dwellings
  • Septic inspection
  • Well permit
  • Agricultural exemption
  • Short-term rentals
  • Permit fees

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Unanswered questions are usually a sign that Town of Duncan publishes no rule on the point, not that none exists. Spartanburg County’s page lists the county offices to call.

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