Bolthole Index

Mercer County, New Jersey

Zoning, building permits and septic rules in Hopewell Township, New Jersey

Hopewell Township, New Jersey requires a building permit from the township construction official before anyone erects or alters a building or structure1. The township adopts and enforces its own zoning ordinance in Chapter 172. Septic systems and private wells are permitted by the township Board of Health, not Mercer County34.

At a glance

Building permit
Required from the township construction official1
Zoning
Township ordinance, Chapter 17, district by district2
Septic
Township Board of Health, on top of state rules3
Wells
Well permit from the Board of Health4
R-150 minimum lot
60,000 sq ft (40,000 clustered)5
Owner-builder
Allowed with an affidavit filed before the certificate of occupancy6

Who to call

Building permits

Hopewell Township Construction Department

Building permits, plan review and inspections under the New Jersey Uniform Construction Code inside Hopewell Township.

609-737-0612

201 Washington Crossing - Pennington Road, Lower Level, Titusville, NJ 08560

Online permits →

Zoning

Hopewell Township Zoning Office

Zoning permits and zoning-ordinance review inside Hopewell Township.

609-737-0605 x6640

201 Washington Crossing-Pennington Rd, Lower Level, Titusville, NJ 08560

Septic permits

Hopewell Township Health Department

Septic system permits and private-well testing inside Hopewell Township.

609-737-0120

201 Washington Crossing - Pennington Road, Lower Level, Titusville, NJ 08560

Roads & driveways

Mercer County Office of the County Engineer

County road permits, including driveways onto a county road, and pre-application review for development affecting county roads or drainage.

(609) 989-6600

640 South Broad Street, P.O. Box 8068, Trenton, NJ 08650-0068

Contact details are copied from each office’s official page and were checked against it on October 13, 2026.

Off-grid gear

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

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Do you need a building permit in Hopewell Township, NJ?

Yes. Hopewell Township's code says no one may erect, construct, alter, repair, remodel, convert, remove or destroy a building or structure without first obtaining a building permit from the construction official, except as the township's ordinances or State law expressly provide1. The permit sits on top of New Jersey's statewide Uniform Construction Code, so the township Building Department also inspects the work as it goes7.

New buildings need a certificate of occupancy before anyone moves in8. The minimum building permit fee is $65, and other permit types and trades can add fees9.

Hopewell Township is not a county-administered area: in New Jersey the municipality issues building permits, not Mercer County10.

Who issues building permits in Hopewell Township, and how do you reach them?

The Hopewell Township Construction Department enforces the State Uniform Construction Code for new residential, commercial and industrial construction11. It is at 201 Washington Crossing - Pennington Road, Lower Level, Titusville, and takes calls at 609-737-061211. Applications run through the township's online permit portal listed on the department's page.

Zoning approval is a separate step handled by the Zoning Office at 609-737-0605 x664012.

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

Hopewell Township adopts and administers its own zoning ordinance in Chapter 17, and the rules differ by district2. The code lists residential districts R-150, R-100, R-75, R-50, R-5 and R-6, plus the Mountain and Valley Resource Conservation districts and several commercial and industrial districts13. Mercer County does not zone unincorporated land in New Jersey, so the township ordinance is the one that applies14.

In the R-150 district, single-family detached dwellings are the permitted residential use2. A conventional design needs a minimum lot area of 60,000 square feet; a cluster design needs 40,0005. Setbacks for the conventional design are 75 feet in front, 50 feet on each side and 50 feet in the rear15. Maximum lot coverage in R-150 is 15%16.

Confirm your parcel's district with the Zoning Office before you buy, because those figures apply to R-150 only5.

How do septic permits work in Hopewell Township?

Applications for onsite sewage disposal systems in Hopewell Township go to the township Board of Health on its approved application form3. The Health Department also tests private wells and issues septic permits17. Mercer County itself does not license septic systems18.

The township ordinance adds site-specific soil testing, lot-area and system-location rules on top of the state's N.J.A.C. 7:9A standards19. Plan on soil testing before design.

Wells need their own permit: nobody may locate, construct, repair, deepen, abandon or alter a well without first receiving a well permit from the Board of Health4. If a public sewer is available, connecting needs approval of the Township Committee where law or the water quality management plan requires it20.

Can you live in an RV or tiny home on your land in Hopewell Township?

We could not confirm a township rule on living in an RV, a tiny home, a manufactured home or an accessory dwelling on a lot in Hopewell Township. The code's recreational-vehicle provisions that we found address storage, not residential occupancy. Ask the Zoning Office at 609-737-0605 x6640 before you buy or park anything on the lot12.

New Jersey limits manufactured HUD homes used as dwellings statewide, so a manufactured home still needs township zoning and building approval21.

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

  1. Confirm the parcel's zoning district and dimensional rules with the Zoning Office12.
  2. If the lot will not have public sewer, arrange soil testing and apply to the Board of Health for a septic permit; apply for a well permit the same way34.
  3. Apply for a building permit from the Construction Department1.
  4. Build, and call for the required inspections during construction7.
  5. Owner-builders file an affidavit with the construction official certifying that the work conforms to law before a certificate of occupancy can be issued6.
  6. Obtain the certificate of occupancy8.

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

Mercer County does not issue building permits or zoning in Hopewell Township; its role is county-level planning, farmland preservation and permits for driveways onto a county road22. A driveway onto a state highway needs a state access permit23. For land elsewhere in the county, see the Mercer County page.

Township floodplain and driveway rules exist in the code, but we could not confirm their requirements, so ask the township before you buy. Mercer County's effective property tax rate is 2.5%24.

Watch-outs

  • Dimensional figures in this guide apply only to the R-150 district; other districts differ, so confirm the parcel's district with the Zoning Office13.
  • Accessory structures such as sheds, barns and garages and pools need zoning permits in addition to any building permit12.
  • We could not confirm township rules on RV living, tiny homes, accessory dwellings, short-term rentals or agricultural permit exemptions; ask the Zoning Office before relying on any of them12.

Sources

  1. Article II: Permits and Certificates; Enforcement (Hopewell Township), quoted and re-checked
  2. Chapter 17: Land Use and Development (Hopewell Township), quoted and re-checked
  3. ecode360.com (Hopewell Township), quoted and re-checked
  4. ecode360.com (Hopewell Township), quoted and re-checked
  5. Article IX: Zoning Districts (Hopewell Township), quoted and re-checked
  6. N.J.A.C. 5:23, Uniform Construction Code (New Jersey statewide rule), quoted and re-checked
  7. The New Jersey State Uniform Construction Code (Hopewell Township), quoted and re-checked
  8. Article II: Permits and Certificates; Enforcement (Hopewell Township), quoted and re-checked
  9. Chapter 10: Fees and Permits (Hopewell Township), quoted and re-checked
  10. NJ Dept. of Community Affairs - Uniform Construction Code (2026 county census)
  11. Hopewell Township Construction Department (hopewelltwp.org)
  12. Hopewell Township Zoning Office (hopewelltwp.org)
  13. Article IX: Zoning Districts (Hopewell Township), quoted and re-checked
  14. P.L. 2013, c.106 — Municipal Land Use Law amendments (New Jersey statewide rule), quoted and re-checked
  15. Article IX: Zoning Districts (Hopewell Township), quoted and re-checked
  16. Article IX: Zoning Districts (Hopewell Township), quoted and re-checked
  17. Hopewell Township Health Department (hopewelltwp.org)
  18. NJDEP Division of Water Quality - Septic Permitting Information (2026 county census)
  19. ecode360.com (Hopewell Township), quoted and re-checked
  20. Chapter 19: Sewer and Water Matters (Hopewell Township), quoted and re-checked
  21. Manufactured/Modular Buildings Program (New Jersey statewide rule), quoted and re-checked
  22. Mercer County Office of the County Engineer (mercercounty.org)
  23. Major Access Permits (New Jersey statewide rule), quoted and re-checked
  24. Effective property tax rate: Bolthole Index county data

Written October 13, 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 Hopewell Township

Hopewell Township’s own rules

  • Building permitRequired

    Erection, construction, alteration, repair, remodeling, conversion, removal, or destruction of a building or structure inside Hopewell Township.

    • Exceptions may be provided by township ordinances or State law.
    • Where applicable, public improvements must be constructed, inspected, and approved before permit issuance, unless modified by an approved developer's agreement and construction phasing plan.
    “No one shall erect, construct, alter, repair, remodel, convert, remove or destroy any building or structure without first obtaining a building permit from the construction official except as expressly provided in these ordinances or by State law.”
  • Certificate of occupancyRequired

    New construction, reconstruction, alteration, conversion, or installation of a structure or building inside Hopewell Township.

    • All applicable UCC, site plan, subdivision, and plot plan requirements must be satisfied.
    • An exception applies to an as-built grading survey for an addition to an existing single-family residence when the addition does not exceed 25% of gross floor area and does not require a bulk variance.
    • Unfinished site work may be covered by a performance guarantee.
    “A certificate of occupancy must be obtained pursuant to the Uniform Construction Code for all new constructions, reconstructions, alterations, conversions or installations of a structure or building.”
  • Local zoningPresent

    Land inside Hopewell Township; the township adopts and administers its own zoning ordinance in Chapter 17.

    • Zoning requirements vary by district and use.
    “R-150 District: Residential Uses. Only single-family detached dwellings and conversions (section 17-145) are permitted as residential uses in this district.”
  • Zoning districtsPublished

    Zoning districts inside Hopewell Township.

    • The code lists residential districts R-150, R-100, R-75, R-50, R-5, R-6, MRC, VRC, and multiple commercial, industrial, and inclusionary districts.
    • District-specific dimensional and use rules apply.
    “§ 17-159 RESIDENTIAL: R-150, R-100, R-75, R-50, R-5 AND R-6. § 17-160 MOUNTAIN RESOURCE CONSERVATION (MRC) AND VALLEY RESOURCE CONSERVATION (VRC) DISTRICTS.”
  • Who permits septicLocal

    Onsite sewage disposal systems inside Hopewell Township.

    • Township requirements supplement N.J.A.C. 7:9A and may impose more stringent requirements.
    • The Township Board of Health administers the local requirements.
    “Applications for onsite sewage disposal systems shall be made to the board of health on the approved township application form.”
  • Off-grid sanitationLimited

    Onsite sanitation using individual sewage disposal systems inside Hopewell Township.

    • Onsite systems are subject to township Board of Health approval, soil testing, lot-area, location, design, installation, and State N.J.A.C. 7:9A requirements.
    • Alternative systems and holding tanks are subject to additional conditions.
    “It is determined to be in the interest of public health, safety and welfare to develop an ordinance to provide site specific requirements in the conducting of soil testing, specifying lot area, restricting system locations and providing additional design and installation requirements for onsite sewage disposal systems in Hopewell Township. These requirements are in addition to N.J.A.C. 7:9A (Adopted by reference as Ordinance 16-3 on 7-16-1990).”
  • Well permitRequired

    Locating, constructing, repairing, deepening, abandoning, decommissioning, altering, or using an existing well for a nonessential use inside Hopewell Township.

    • The Board of Health schedules and performs inspections as part of permit requirements.
    • Emergency no-water activity may proceed before inspection and permit, but the Board of Health must be notified as soon as possible and no later than the next business day.
    • A well-use certificate of compliance is required before operation.
    “No person shall locate, construct, repair, deepen, abandon, decommission or alter any well, or utilize an existing well for any nonessential use, without first receiving a well permit from the board of health.”
  • Mandatory utility hookupConditional

    Connection of a home or other property inside Hopewell Township to a public sewer system.

    • Connection or an extension/addition to an existing connection requires Hopewell Township Committee approval when that approval is required or permitted by applicable law, regulations, rules, or a water quality management plan.
    • The ordinance excerpt does not establish a universal distance-to-sewer connection threshold.
    “No person shall be permitted to connect to any public sewer system, or to perform any extension or addition to an existing sewer connection, except through and with the approval of the Hopewell Township Committee, provided such Hopewell Township Committee approval is required or permitted pursuant to applicable law, regulations, rules or water quality management plan for the connection, extension or addition to or of a public sewer system, which approval must be received through the affirmative vote of not less than two-thirds of the full membership thereof.”
  • Permit feesPublished (with conditions)

    Building permits inside Hopewell Township.

    • The cited fee is a minimum; other disciplines and permit types may have additional fees under Chapter 10 and applicable State schedules.

    minimum building permit fee: 65 USD

    “The minimum building permit fee shall be $65.”

Rules another office applies inside Hopewell Township

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

  • InspectionsRequired

    UCC-regulated construction inside Hopewell Township.

    • Inspections are conducted during construction by the code official or inspector.
    • The local enforcing agency is the township Building Department under the State Uniform Construction Code.
    “During construction, the code official or inspector conducts regular inspections to ensure that the work performed complies with the UCC. The permit applicant is responsible for notifying the local enforcing agency that the project is ready for inspection.”
  • Minimum lot sizeSpecified

    Single-family detached dwellings in Hopewell Township's R-150 Residential District; district-specific township zoning rule.

    • For non-cluster design, the minimum lot area is 60,000 square feet.
    • For cluster design, the minimum lot area is 40,000 square feet.
    • The cited district also specifies minimum width, depth, yards, height, coverage, and density.

    minimum lot area: 60000 square feet (40,000 square feet for cluster design)

    “R-150 | Non-Cluster Design | Cluster Design (Section 17-79) Minimum Lot Area | 60,000 square feet | 40,000 square feet”
  • SetbacksSpecified

    Single-family detached dwellings in Hopewell Township's R-150 Residential District; district-specific township zoning rule.

    • For non-cluster design, front yard is 75 feet, each side yard is 50 feet, and rear yard is 50 feet.
    • For cluster design, each side yard is 40 feet; front and rear yards remain 75 and 50 feet respectively.

    minimum front yard: 75 feet · minimum side yard: 50 feet (40 feet each for cluster design) · minimum rear yard: 50 feet

    “Minimum Front Yard | 75 feet | 75 feet Minimum Side Yard | 50 feet ea. | 40 feet ea. Minimum Rear Yard | 50 feet | 50 feet”
  • Lot coverageSpecified

    Single-family detached dwellings in Hopewell Township's R-150 Residential District; district-specific township zoning rule.

    • Maximum lot coverage is 15% for both non-cluster and cluster design.

    maximum lot coverage: 15 percent

    “Maximum Lot Coverage | 15% | 15% Minimum Open Space | — | 25%”

Still unanswered

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

  • Minimum dwelling size — Single-family dwellings inside Hopewell Township.
  • Living in an RV — Occupancy of a recreational vehicle as a residence on land inside Hopewell Township.
  • Camping on your land — Temporary camping on private land inside Hopewell Township.
  • Tiny homes — Tiny-home occupancy on land inside Hopewell Township.
  • Manufactured homes — Manufactured-home occupancy on land inside Hopewell Township.
5 more unanswered
  • Accessory dwellings
  • Agricultural exemption
  • Driveway access
  • Building in a floodplain
  • Short-term rentals

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 Hopewell Township publishes no rule on the point, not that none exists. Mercer County’s page lists the county offices to call.

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