Bolthole Index

Providence County, Rhode Island

Building permits, zoning and septic rules in Johnston, Rhode Island

The Town of Johnston, Rhode Island adopts its own zoning ordinance, Chapter 340 of the town code1. Building permits follow the Rhode Island State Building Code and are issued by the town, not by Providence County, which has no building authority2. Septic permits for homes without public sewer come from the state Department of Environmental Management3.

At a glance

Building permit
Required under the Rhode Island State Building Code; the town issues it4
Zoning
Town zoning ordinance, Chapter 340, with named districts such as R-40 and R-2015
Septic
State permit from RI DEM where no public sewer is available; town rules also apply67
RV living
Limited: occupying a trailer on a lot is restricted; one unoccupied trailer may be kept in a garage or rear yard8
Accessory dwelling
One per lot allowed by state law when statutory conditions are met9
Owner-builder
Owner-occupants may do their own work without contractor registration, but permits and inspections still apply10

Who to call

Building permits

Town of Johnston Building Division

Building, plumbing, mechanical, electrical, demolition, sign and solar permits for the Town of Johnston; permitting is handled online

Septic permits

Rhode Island DEM Office of Water Resources – OWTS Program

Statewide septic (OWTS) permitting, design review and inspection, including in Johnston

(401) 222-3961

dem.owts@dem.ri.gov

235 Promenade Street, Providence, RI 02908

Contact details are copied from each office’s official page and were checked against it on October 14, 2026.

Off-grid gear

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

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Does Johnston, RI have zoning, and what does it mean for RVs and lot size?

Yes. The Town of Johnston adopts its own zoning ordinance, Chapter 340 of the town code, and divides the town into zoning districts1. The districts include R-40 and R-20, and the zoning map is filed with the town clerk5.

Minimum lot sizes, setbacks and which uses each district allows sit in the use and dimensional tables at the end of Chapter 3401. We could not confirm those figures, so ask the town's Planning and Zoning Division which district a parcel is in before you buy.

On RVs, Johnston's trailer chapter says no one may park or occupy a trailer on a lot, whether or not a dwelling stands on it, except one unoccupied trailer kept in a garage or rear yard. Violations are a misdemeanor with a fine of $50 to $100 per day8. Living in an RV on a Johnston lot is therefore not a practical plan.

Do you need a building permit in Johnston, RI, and who issues it?

Yes. Rhode Island requires a permit for construction, enlargement, alteration, removal and demolition under the State Building Code, and the one- and two-family work a homeowner does is governed by the state's One and Two-Family Dwelling Code4. Counties in Rhode Island cannot require building permits, so the town is the office to deal with2.

In Johnston the Building Division issues building, plumbing, mechanical, electrical, demolition and solar permits, and the town says permitting is conducted online while you can still stop in the offices to discuss a project11. Work under a permit must be inspected, and a new building needs a certificate of use and occupancy before it is used12.

An owner who lives in and builds their own single-family home may be exempt from contractor registration, but permits and inspections still apply10. We could not confirm Johnston's fee schedule; ask the Building Division.

How do septic permits work in Johnston, RI?

Where no public sewer is available, a house in Johnston must connect to an on-site wastewater system that meets both town and Rhode Island DEM requirements7. DEM's OWTS Program is the permitting authority for septic systems in the state3, and a permit is required for a new structure that will use one6. A licensed designer must witness the installation13.

Where a public sewer abuts the street or easement and the town's director finds it accessible with adequate capacity, an occupied building must connect to it instead14. Contact the15 at (401) 222-3961 for septic questions.

Building permits and zoning are the town's job; septic stays with the state.

Can you live in an RV, tiny home or accessory dwelling in Johnston, RI?

RVs: Johnston limits trailer occupancy on lots, as described above8. Statewide, extended RV stays are allowed in recreational vehicle parks and campgrounds, not on a private lot16.

Accessory dwellings: Rhode Island allows one accessory dwelling unit per lot in residential zoning districts when the statutory conditions are met9.

Manufactured homes: state law allows manufactured homes as single-family homes on lots zoned for single-family use17.

We could not confirm how Johnston's use table treats tiny homes or minimum dwelling size; ask the Planning and Zoning Division.

What stays with the state and county when you build in Johnston, RI?

Septic permits come from RI DEM, not the town3. A driveway onto a state highway needs a Rhode Island DOT access permit18. Projects that may alter freshwater wetlands, buffers or floodplains need DEM approval19.

Providence County itself has no zoning authority20. The county page at Providence County covers the wider area.

Providence County's effective property tax rate is 1.4% and the median bill is $4,661 a year2122.

Watch-outs

  • We could not confirm Johnston's minimum lot sizes, setbacks, fees or tiny-home rules; the Planning and Zoning Division and the Building Division can answer them11.
  • Soil ratings are poor for conventional drain fields in Providence County, so expect a site evaluation and possibly an engineered system23.
  • Johnston's town code ties septic to both town and DEM rules, so check Chapter 332 on wastewater management with the town before designing a system7.

Sources

  1. Johnston Code Ch. 340 Zoning, Article III: Zoning Districts and Map; Use Table (Town of Johnston), quoted and re-checked
  2. R.I. Gen. Laws § 23-27.3-100.1 — Short title — Applicability (Rhode Island statewide rule), quoted and re-checked
  3. Obtaining a Permit for a New Home’s Septic System (Rhode Island statewide rule), quoted and re-checked
  4. R.I. Gen. Laws § 23-27.3-113.1 — When permit is required (Rhode Island statewide rule), quoted and re-checked
  5. Johnston Code Ch. 340 Zoning, Article III: Zoning Districts and Map; Use Table (Town of Johnston), quoted and re-checked
  6. Rules Establishing Minimum Standards Relating to Location, Design, Construction and Maintenance of Onsite Wastewater Treatment Systems (Rhode Island statewide rule), quoted and re-checked
  7. Johnston Code Ch. 279 Sewers (Town of Johnston), quoted and re-checked
  8. Johnston Code Ch. 319 Trailers and Mobile Homes (Town of Johnston), quoted and re-checked
  9. R.I. Gen. Laws § 45-24-73. Design standards required for accessory dwelling units (Rhode Island statewide rule), quoted and re-checked
  10. RI Contractors' Registration and Licensing Board - FAQs (2026 county census)
  11. Town of Johnston Building Division (johnstonri.gov)
  12. R.I. Gen. Laws § 23-27.3-120.1 — New buildings (Rhode Island statewide rule), quoted and re-checked
  13. Rules Establishing Minimum Standards Relating to Location, Design, Construction and Maintenance of Onsite Wastewater Treatment Systems (Rhode Island statewide rule), quoted and re-checked
  14. Johnston Code Ch. 279 Sewers (Town of Johnston), quoted and re-checked
  15. Rhode Island DEM Office of Water Resources – OWTS Program (dem.ri.gov)
  16. R.I. Gen. Laws § 32-7-7 — Definitions (Rhode Island statewide rule), quoted and re-checked
  17. R.I. Gen. Laws § 45-24-37. General provisions — Permitted uses (Rhode Island statewide rule), quoted and re-checked
  18. Physical Alteration Permit Application Manual (Rhode Island statewide rule), quoted and re-checked
  19. Rules and Regulations Governing the Administration and Enforcement of the Freshwater Wetlands Act (Rhode Island statewide rule), quoted and re-checked
  20. R.I. Gen. Laws § 45-24-50 — Adoption — Power of council to adopt (Rhode Island statewide rule), quoted and re-checked
  21. Effective property tax rate: Bolthole Index county data
  22. Median property tax bill: Bolthole Index county data
  23. 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

Written October 14, 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 Johnston

Town of Johnston’s own rules

  • Local zoningPresent

    All land inside Johnston town; the town adopts its own zoning ordinance (Chapter 340)

    • Table of use regulations and table of dimensional regulations are at the end of Chapter 340 and were not read.
    “for the purpose of this chapter, the town of johnston is divided into the following zoning districts:”
  • Zoning districtsPublished

    Zoning districts inside Johnston town (R-40, R-20, and others through planned districts; zoning map on file with the town clerk)

    • The zoning map is filed in the office of the town clerk.
    “the boundaries of the above zoning districts are hereby established as shown on the map filed in the office of the town clerk”
  • Living in an RVLimited

    Trailers (any wheeled vehicle or structure designed for sleeping quarters, including RVs) on lots inside Johnston town

    • Only one unoccupied trailer may be kept in an accessory private garage or rear yard, with no living quarters or business.
    • Exceptions for trailers used for building construction or public works and for trailer sales lots.
    • Emergency or temporary stopping on streets limited to one hour.
    • Violation is a misdemeanor, fine $50 to $100 per day.
    “no person shall park or occupy any trailer on the premises of any occupied dwelling or on any lot, tract or parcel of land which is not a part of the premises of any occupied dwelling, except the parking of only one unoccupied trailer in an accessory private garage or in a rear yard in any district is permitted”
  • Who permits septicMixed (with conditions)

    On-site wastewater treatment systems where no public sewer is available inside Johnston town

    • Must comply with both town requirements (Chapter 332 Wastewater Management) and RI DEM requirements.
    • Chapter 332 text not read.
    “where a public sanitary sewer is not available, the building sewer shall be connected to an owts complying with the requirements of the town and the state of rhode island department of environmental management (dem).”
  • Mandatory utility hookupConditional

    Buildings used for human occupancy abutting a street or easement with a public sanitary sewer inside Johnston town

    • Connection required only where the director determines the public sewer is accessible and has adequate capacity.
    • Narragansett Bay Commission rules also apply; the more stringent requirement prevails.
    • Violation fine up to $500 or 30 days imprisonment per § 279-17.
    “provided that the public sewer is determined by the director to be accessible and contain adequate capacity to serve said property”

Still unanswered

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

  • Building permit — Building permits inside Johnston town
  • Owner-builder exemption — Owner-builder rules inside Johnston town
  • Building code adopted — Building code inside Johnston town
  • Inspections — Building inspections inside Johnston town
  • Certificate of occupancy — Certificates of occupancy inside Johnston town
20 more unanswered
  • Minimum dwelling size
  • Minimum lot size
  • Setbacks
  • Lot coverage
  • Building height
  • Camping on your land
  • Tiny homes
  • Manufactured homes
  • Accessory dwellings
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit
  • Agricultural exemption
  • Subdividing land
  • Driveway access
  • Building in a floodplain
  • Short-term rentals
  • Permit fees
  • Permit process

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

← All of Providence County: county rules, score and offices