Building permits, zoning and septic rules in Union County, North Carolina

At a glance

Building permit

Required before most construction, with limited exceptions for qualifying minor work¹

Zoning

Yes — Union County administers zoning within its jurisdiction; municipal jurisdictions may apply separately⁴

Septic permit

Union County Environmental Health, On-Site Water Protection Program³

Owner-builder exemption

Conditional — an owner may act as their own general contractor through a verified affidavit, but must personally manage the work and intend to occupy the home for at least 12 months⁵

Small-project permit exception

Qualifying work of $40,000 or less may be exempt, but structural, electrical, HVAC, roofing and other listed work is excluded¹

Tiny home (400 sq ft or less)

Allowed statewide as a single dwelling under the NC Residential Code's tiny-house appendix, plus local zoning, septic and utility approval⁶

Agricultural exemption

A farmer may build for personal use on owned land used in the farming business, subject to the exemption's conditions⁷

Median property tax bill

About $2,298 a year at an effective rate near 0.6%⁸⁹

Who to call

Contact details are copied from each office’s official page and were checked against it on October 5, 2026.

Do you need a building permit in Union County, North Carolina?

Union County construction is subject to the North Carolina State Building Code, which is adopted for statewide implementation and enforced locally¹⁰. A permit is required before construction, reconstruction, alteration, repair, movement, removal or demolition begins unless a statutory exception applies¹. Qualifying work costing $40,000 or less may be exempt when it follows the current code, but the exception excludes listed structural, plumbing, heating, cooling, electrical, roofing and Fire Code work¹. Submit a completed building permit application with zoning approval and either a water/sewer accessibility letter or a septic permit or waiver¹¹. Required code inspections follow the permit, and the inspector conducts the inspections requested by the permit holder for each scheduled inspection¹². A new, enlarged, altered or moved building cannot be occupied until the inspection department issues a certificate of compliance, although a temporary certificate may allow safe occupancy before final completion¹³.

Who is the Union County building department, and how do you reach them?

Union County Building Code Enforcement Division issues permits and handles inspections where the county has authority; Monroe and Waxhaw are outside the county's building-permit authority². The county's online plan-review and permitting service accepts applications and inspection requests, and permit searches remain available without an account¹⁴. Reach Building Code Enforcement at 500 N. Main St. Suite 47 in Monroe for permit questions¹¹. The division's zoning administrator enforces the Union County Development Ordinance, including property use, setbacks, violations and floodplain rules for unincorporated Union County¹¹. Residential permit cost is based on heated and unheated square footage¹¹. Union County has published building-permit fees, but the accessible schedule is marked effective in 2024 while the county identifies a newer schedule for 2026, so ask the office for the current price before budgeting¹⁵.

Does Union County have zoning?

Union County administers zoning within its planning and development jurisdiction, while municipal planning and land-use jurisdictions may apply separately⁴. The county ordinance governs property use, setbacks and floodplain rules in unincorporated Union County¹¹. Union County's zoning jurisdiction does not include Fairview, Indian Trail, Lake Park, Marshville, Marvin, Mineral Springs, Monroe, Stallings, Unionville, Waxhaw, Weddington, Wesley Chapel or Wingate, so identify the parcel's jurisdiction before applying county rules¹¹. Bona fide farm property is exempt from county zoning for farm purposes, including a code-compliant residence occupied by the farm's owner, lessee or operator, but nonfarm uses remain subject to zoning¹⁶. A person engaged in farming also has a conditional contractor-licensing exception when building on personally owned land used in the farming business for that person's own use⁷.

How do septic permits work in Union County?

Union County Environmental Health's On-Site Water Protection Program performs soil and site evaluations, issues permits, and inspects on-site wastewater (septic) systems to prevent groundwater contamination and protect public health³¹⁷. Statewide, an improvement permit and construction authorization are required before you build, relocate, install or repair a wastewater system, unless you use the engineered-option or Authorized On-Site Wastewater Evaluator permit path¹⁸. The construction authorization is required both to install septic system components and to obtain your building permit, so a delay at Environmental Health can delay your building permit too¹⁷. A local health department inspection has to confirm the system was installed or repaired correctly before it can be covered or used¹⁹. Only 27.3% of Union County's soil is rated without severe limits for a conventional septic drain field, so budget for the chance of an engineered or alternative system on a given parcel²⁰. A chemical or portable toilet can supplement a system during peak use but can't substitute for a properly connected wastewater system where the state code requires one, so there's no shortcut around permitting if you plan to live on the land²¹.

Can you live in an RV, tiny home or manufactured home on your land in Union County?

North Carolina allows a code-compliant tiny home as a permanent single-family dwelling, but local zoning, utility, septic and permit requirements still apply⁶. A local government cannot exclude manufactured homes from its entire zoning jurisdiction or exclude them because of age, but it may impose appearance and dimensional standards; zoning, installation, septic and other approvals still apply²². Union County does not provide a confirmed blanket answer for an RV used as a residence, so ask the Building Code Enforcement Division about a parcel under county zoning or the relevant town about land in a municipality outside county zoning jurisdiction¹¹²³.

Building a home in Union County: the steps, in order

1. Confirm whether Union County or a municipality has zoning and building-permit authority over the parcel²¹¹.
2. If the parcel lacks public sewer, apply to Union County Environmental Health for a soil/site evaluation and septic authorization before fixing the house location¹⁷.
3. Get zoning approval, then use the county's online permitting service to submit the building application and schedule inspections²¹⁴.
4. Include the septic permit or waiver or the required water/sewer accessibility letter¹¹.
5. If acting as owner-builder, file the verified affidavit, personally manage the construction and attend required inspections unless architect-sealed plans qualify for the exception; the home must be intended for the qualifying owner's occupancy for at least 12 months⁵.
6. Arrange the required inspections before work is covered or the project advances¹².
7. If temporary electrical service is needed, submit the application, affidavit and $100 fee and pass the electrical inspection; the service lasts 90 days, temporary gas is unavailable, and occupancy remains prohibited²⁴²⁵.
8. Obtain a certificate of compliance or temporary certificate of occupancy before moving in¹³.

What should you check before you buy land in Union County?

Test the soil before you count on a standard septic system: only 27.3% of Union County's soil rates free of severe limits for a conventional drain field, and Environmental Health's soil/site evaluation is the way to confirm a parcel before closing²⁰¹⁷. Check whether the parcel is inside Union County's zoning jurisdiction or a municipality, since rules, setbacks and floodplain review differ by jurisdiction¹¹. If the land is used for farming, bona fide farm purposes are exempt from county zoning and, outside a municipality's building-rules jurisdiction, qualifying farm buildings are exempt from building-rule enforcement¹⁶²⁶. Farmland has recently traded around $6,148 an acre, and typical countywide home value is about $456,000²⁷²⁸. The effective property tax rate is near 0.6%, the median bill is about $2,298 a year, and a typical homeowner's insurance premium is near $1,307 a year⁹⁸²⁹. The nearest city of 100,000 or more is about 21 miles from the county center; roughly 48.8% of the county is wooded, and about 97.4% has a slope of 15% or less³⁰³¹³².

Watch-outs

• Union County zones unincorporated land itself, but Fairview, Indian Trail, Lake Park, Marshville, Marvin, Mineral Springs, Monroe, Stallings, Unionville, Waxhaw, Weddington, Wesley Chapel and Wingate all zone their own land, so confirm which jurisdiction covers a specific parcel before assuming county rules apply¹¹.
• A septic construction authorization is required both to install septic system components and to obtain a building permit, so a delay at Environmental Health can delay your building permit too¹⁷.
• Temporary electrical service during construction does not authorize occupancy, may be revoked and requires a $100 fee, an application, an affidavit and an inspection²⁴²⁵.
• Occupying a new, enlarged, altered or moved building before the inspection department issues a certificate of compliance or temporary certificate of occupancy is a Class 1 misdemeanor¹³.

Sources

1. G.S. 160D-1110. Building permits, quoted and re-checked
2. unioncountync.gov, quoted and re-checked
3. On-site Wastewater Disposal (Septic) Systems (2026 county census)
4. Development Services, quoted and re-checked
5. ncleg.gov, quoted and re-checked
6. Guidelines for Tiny Homes in North Carolina (North Carolina statewide rule), quoted and re-checked
7. G.S. 87-1. Farming exception, quoted and re-checked
8. Median property tax bill: Bolthole Index county data
9. Effective property tax rate: Bolthole Index county data
10. Codes, quoted and re-checked
11. Union County Building Code Enforcement Division (unioncountync.gov)
12. G.S. 160D-1104. Duties and responsibilities, quoted and re-checked
13. G.S. 160D-1116. Certificates of compliance; temporary certificates of occupancy, quoted and re-checked
14. Union County Online Plan Review and Permitting Service, quoted and re-checked
15. Building Code Enforcement Fee Schedule, quoted and re-checked
16. G.S. 160D-903. Agricultural uses (North Carolina statewide rule), quoted and re-checked
17. Union County Environmental Health – On-Site Water Protection Program (unioncountync.gov)
18. G.S. 130A-336. Improvement permit and construction authorization required (North Carolina statewide rule), quoted and re-checked
19. G.S. 130A-337. Inspection; operation permit required (North Carolina statewide rule), quoted and re-checked
20. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
21. G.S. 130A-335 PDF, subsection (h) (North Carolina statewide rule), quoted and re-checked
22. Chapter 160D, G.S. 160D-910. Manufactured homes (North Carolina statewide rule), quoted and re-checked
23. Development Services (2026 county census)
24. Application for Temporary Electrical Utility, quoted and re-checked
25. Application for Temporary Electrical Utility, quoted and re-checked
26. NC General Statutes Pertaining to the Enforcement of the NC State Building Code (North Carolina statewide rule), quoted and re-checked
27. Farmland value per acre (USDA census): Bolthole Index county data
28. Typical home value (Zillow): Bolthole Index county data
29. Typical home insurance premium: Bolthole Index county data
30. Straight-line distance from the county center to the nearest city of 100,000+ people: Bolthole Index county data
31. Wooded share of land: Bolthole Index county data
32. Share of land at 15% slope or less: Bolthole Index county data

Written October 5, 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.