Bolthole Index

Hunterdon County, New Jersey

Zoning, building permits and septic in Union Township, Hunterdon County, NJ

Building in Union Township, New Jersey takes a township zoning permit first, then a construction permit from the state Department of Community Affairs, which runs the building code for the township1. DCA will not process a construction permit until the township zoning officer approves the project2. Septic permits are a separate track through Hunterdon County Environmental Health3.

At a glance

Zoning
Yes. The township zones, with multiple districts, each with its own minimum home site, yard and building requirements4
Building permit
Required. Zoning approval first, then a state construction permit through DCA2
Building inspections
Required; DCA's northern code enforcement office performs them5
Septic
Hunterdon County Environmental Health handles septic design review and inspections3
Driveways
Zoning review required for installing, altering or paving a driveway6
Owner-builder
Owner-built homes need an affidavit filed with the construction official before a certificate of occupancy7

Who to call

Zoning

Union Township Zoning Officer

Zoning permits, plot plan review, driveway and change-of-use review; refers variances to the board of adjustment

908-735-8027

zoning@uniontwp-hcnj.org

140 Perryville Rd, Hampton, New Jersey 08827

Building permits

NJ Department of Community Affairs, Office of Local Code Enforcement (Northern)

Construction permits, plan review, inspections and certificates for Union Township under the State Uniform Construction Code

908-713-0722

171 Route 173, Suite 101 Asbury, NJ 08802

Septic permits

Hunterdon County Health Department, Office of Environmental Health

Septic design review, installation inspections and certification of completed systems

908-788-1351

314 State Route 12

Contact details are copied from each office’s official page and were checked against it on October 24, 2026.

Off-grid gear

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

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Does Union Township, NJ have zoning, and what does it mean for lot size and setbacks?

Yes. Union Township is made up of multiple zoning districts, each with its own minimum home site, yard and building requirements4. Those requirements cover front, side and rear setbacks, maximum lot coverage, habitable floor area and structure height8. Which numbers apply depends on the district your parcel sits in, and we could not confirm the district-by-district figures. The township posts a zoning map, and the zoning office can tell you a parcel's classification9.

New Jersey counties cannot zone, so Hunterdon County does not set these rules for you10. We also could not confirm what the township ordinance says about RVs, tiny homes or accessory dwellings; ask the Union Township zoning officer before you buy.

Do you need a building permit in Union Township, and who issues it?

Yes, construction work in Union Township needs a construction permit under the State Uniform Construction Code2. The township does not run its own building department: the state Department of Community Affairs, Office of Local Code Enforcement (Northern), issues the permits and performs inspections for Union Township11.

Zoning comes first. The township zoning officer must approve your project before DCA will take the construction permit application11. Statewide, a permit is required before work begins on construction, enlargement, repair, alteration or change of use, with exceptions for ordinary maintenance12. Hunterdon County itself does not issue building permits; the county's own page points permit questions to the municipality13.

How do septic permits work for a home in Union Township?

Septic permits for Hunterdon County come through the county Office of Environmental Health, which reviews septic designs, inspects installations and certifies completed systems3. The county offers an application for a permit to construct, alter or repair an individual subsurface sewage disposal system14. Across New Jersey, the board of health must certify the septic plan before a building permit can be issued, so start the septic evaluation early15.

Soils matter. Only about 10% of Hunterdon County soils rate as not limited for a conventional drain field, so expect a site evaluation and possibly an engineered system16. We could not confirm whether the Union Township board of health adds its own septic rules; ask the township office17.

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

  1. Ask the township zoning officer which district your lot is in and what its minimum home site, yard and height limits are4.
  2. Start septic and well planning with Hunterdon County Environmental Health, since the board of health must certify the septic plan before a building permit issues15.
  3. Submit the township zoning permit application with a plot plan or survey showing existing and proposed development and setbacks18.
  4. Once the zoning officer approves, apply to DCA's northern code enforcement office for the construction permit2.
  5. Request inspections in writing through DCA's online procedure5.
  6. If you built the home yourself, file the owner-built affidavit with the construction official before the certificate of occupancy7.

What stays with Hunterdon County, and what to check before you buy

Septic stays with Hunterdon County Environmental Health3. Subdividing land also involves county review before local approval, and the township requires its own certificate of approval of subdivision1920. Driveways need township zoning review, and a driveway onto a state highway also needs a state access permit621.

For land outside Union Township, see the Hunterdon County page. Hunterdon County's effective property tax rate is about 2%22. We could not confirm township rules on wells, floodplain development or permit fees; ask the zoning officer.

Watch-outs

  • Do not skip the township zoning step: DCA will not process a construction permit until Union Township approves a zoning permit2.
  • The owner-builder exception covers new-home builder registration only, not construction permits or the building code23.
  • We could not confirm Union Township's rules on RV living, tiny homes, accessory dwellings or short-term rentals, so ask the zoning officer before you plan around them9.

Sources

  1. Building & Construction - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  2. Zoning - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  3. Septic Disposal Systems, quoted and re-checked
  4. Zoning - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  5. Building & Construction - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  6. Zoning - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  7. N.J.A.C. 5:23, Uniform Construction Code (New Jersey statewide rule), quoted and re-checked
  8. Zoning - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  9. Union Township Zoning Officer (uniontwp-hcnj.gov)
  10. P.L. 2013, c.106 — Municipal Land Use Law amendments (New Jersey statewide rule), quoted and re-checked
  11. NJ Department of Community Affairs, Office of Local Code Enforcement (Northern) (uniontwp-hcnj.gov)
  12. N.J.A.C. 5:23-2.14, Construction permits—when required (New Jersey statewide rule), quoted and re-checked
  13. Open Public Records Act (OPRA), quoted and re-checked
  14. Septic Disposal Systems, quoted and re-checked
  15. New Jersey Statutes, R.S. 58:11-23 through 58:11-43 (New Jersey statewide rule), quoted and re-checked
  16. 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
  17. Hunterdon County Health Department, Office of Environmental Health (co.hunterdon.nj.us)
  18. Zoning - Union Township, NJ (official township site) (Union Township), quoted and re-checked
  19. County Land Development Standards, quoted and re-checked
  20. Application for Zoning Permit (Z-3, 11/29/2021), Township of Union, Hunterdon County (Union Township), quoted and re-checked
  21. Major Access Permits (New Jersey statewide rule), quoted and re-checked
  22. Effective property tax rate: Bolthole Index county data
  23. New Jersey Department of Community Affairs — Construction Code FAQs for New Home Buyers, quoted and re-checked

Written October 24, 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 Union Township

Union Township’s own rules

  • Certificate of occupancyRequired

    Commercial or industrial property in Union township only

    • Form states it may be used for certificates of occupancy for commercial or industrial properties under township code section 11-1.7.
    “h. _______ certificate of occupancy for commercial or industrial property (§ 11-1.7)”
  • Local zoningPresent (with conditions)

    Land inside Union township's limits (Hampton, Hunterdon County, NJ); the township administers its own zoning permits under its land use code, chapter 30

    • Zoning review and approval by the township zoning officer is required before construction permits can be submitted to the NJ DCA.
    • Zoning permit types listed on the township form cite land use code section 30-12.3 (use permit, building permit/local clearance, occupancy permit, certificate of occupancy, sign, subdivision, minor driveway modification).
    “the township of union is comprised of multiple zoning districts, each with its own particular minimum home site, yard, and building requirements.”
  • Zoning districtsPartial

    Zoning districts of Union township, Hunterdon County

    • The township says it has multiple zoning districts and posts a zoning map; the map and district list were not opened, so the district names are not recorded here.
    “the township of union is comprised of multiple zoning districts, each with its own particular minimum home site, yard, and building requirements.”
  • Minimum dwelling sizeDistrict specific (with conditions)

    Single-family dwellings inside Union township; the minimum habitable floor area varies by zoning district (district values not captured)

    • Numeric habitable floor area minimums per district were not captured; the township schedule of zoning requirements was not reached.
    • Main single-family residential district and any agricultural/rural district to be recorded as separate claims in a follow-up.
    “these requirements include minimum front, side and rear yard setbacks, maximum lot coverage, habitable floor area and structure height.”
  • Minimum lot sizeDistrict specific (with conditions)

    Residential lots inside Union township; minimum home site (lot) size varies by zoning district (district values not captured)

    • Numeric minimum lot area per district not captured; the township schedule of zoning requirements was not reached.
    • Main single-family residential district and any agricultural/rural district to be recorded as separate claims in a follow-up.
    “the township of union is comprised of multiple zoning districts, each with its own particular minimum home site, yard, and building requirements.”
  • SetbacksDistrict specific (with conditions)

    Principal structures on lots inside Union township; minimum front, side and rear yard setbacks vary by zoning district (district values not captured)

    • Numeric setback distances per district not captured; the township schedule of zoning requirements was not reached.
    • The zoning permit form requires a plot plan showing proposed setbacks from property lines.
    “these requirements include minimum front, side and rear yard setbacks, maximum lot coverage, habitable floor area and structure height.”
  • Lot coverageDistrict specific (with conditions)

    Lots inside Union township; maximum lot coverage varies by zoning district (district values not captured)

    • Numeric maximum lot coverage per district not captured.
    “these requirements include minimum front, side and rear yard setbacks, maximum lot coverage, habitable floor area and structure height.”
  • Building heightDistrict specific (with conditions)

    Structures inside Union township; maximum structure height varies by zoning district (district values not captured)

    • Numeric height limits per district not captured.
    “these requirements include minimum front, side and rear yard setbacks, maximum lot coverage, habitable floor area and structure height.”
  • Subdividing landRegulated (with conditions)

    Subdivision of land inside Union township

    • Subdivision requires a certificate of approval under township code section 30-12.8, per the zoning permit form.
    • Subdivision procedure and standards not reviewed.
    “g. _______ certificate of approval of subdivision (§ 30-12.8)”
  • Driveway accessRequired

    Driveway installation, alteration or paving on private land in Union township

    • Zoning review is required; the zoning permit form also lists a minor driveway modification permit under § 30-2.14(b).
    • Driveway width, curb cut and access standards not reviewed.
    “zoning review is also required for the proper display of a residence address, tree removal, driveway installation, driveway alteration or paving”
  • Permit processPublished (with conditions)

    Zoning permit process for construction, alteration and change-of-use projects in Union township

    • Zoning permit application goes to the zoning office first, with a plot plan or survey; DCA construction permits follow after zoning approval.
    • Zoning review is also required for change of use (residential and commercial).
    “the first step is for the homeowner/property owner/tenant or agent to submit a zoning permit application to the zoning office for project review/compliance with the zoning ordinances.”

Rules another office applies inside Union Township

Union Township does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

  • Building permitRequired

    Construction inside Union township limits requiring a construction permit under the State Uniform Construction Code, issued through NJ DCA

    • A Union township zoning permit must be obtained and approved by the zoning officer before DCA will process the construction permit application.
    • Permit types and project thresholds are not stated on the pages reviewed.
    “dca will not process construction permit applications until a union township zoning permit is obtained and approved by the zoning officer.”
  • Building code adoptedAdopted (with conditions)

    New construction and alterations inside Union township limits, enforced by NJ Department of Community Affairs Office of Local Code Enforcement (Northern) under the State Uniform Construction Code

    • The township does not appear to run its own building department; DCA administers the state code for the township.
    • Local zoning review must precede DCA construction permit applications.
    “the office of local code enforcement provides for the administration and enforcement of the state uniform construction code in many smaller municipalities, including union township.”
  • InspectionsRequired

    Construction inside Union township limits performed under a construction permit, inspected by NJ DCA Office of Local Code Enforcement (Northern)

    • As of August 15, 2025, DCA requires inspection requests to be made in writing through an online procedure, per the township page.
    • Specific inspection types are not listed on the page reviewed.
    “services provided include receiving and providing guidance on construction permit applications, review of construction plans, issuance of construction permits, performing required inspections, and issuing certificates and orders, where necessary.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Union Township or Hunterdon County directly.

  • Owner-builder exemption — Owner-builder exemption for a homeowner building their own home in Union township
  • Living in an RV — Occupancy of an RV on private land in Union township
  • Camping on your land — Temporary camping on private land in Union township
  • Tiny homes — Occupancy of a tiny home on private land in Union township
  • Manufactured homes — Occupancy of a manufactured home on private land in Union township
11 more unanswered
  • Accessory dwellings
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit
  • Mandatory utility hookup
  • Agricultural exemption
  • Building in a floodplain
  • 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 Union Township publishes no rule on the point, not that none exists. Hunterdon County’s page lists the county offices to call.

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