Franklin County, ID: Owner-Builder Allowed

Franklin County, Idaho requires a building permit for a home, and zoning applies throughout unincorporated Franklin County^1,2. Agricultural buildings have a code exemption, but they still must meet zoning placement rules³. Southeastern Idaho Public Health handles onsite septic permits, and the septic permit must come before the county building permit^4,5.

At a glance

Building permit: Required for a home¹
Building codes: Adopted by Franklin County³
Zoning: Yes in unincorporated Franklin County; cities maintain their own plans²
Septic permits: Southeastern Idaho Public Health⁴
Agricultural buildings: Exempt from adopted building codes, but zoning placement still applies³
Manufactured homes outside parks: At least 20 feet wide and 900 square feet, with a narrow older-unit exception⁶
Septic soil suitability: 5.3% of soils avoid a severe conventional drain-field limitation⁷
Property taxes: 0.5% effective rate; $1,512 median annual bill⁷

Who to call

Building permits

Franklin County Building Department

Building permits and inspections for Franklin County; the county page says the septic permit must be completed before a building permit can be issued

208-221-6149

randallh@fcidaho.us

561 West Oneida

Zoning

Franklin County Planning & Zoning

Planning, zoning, development-code materials, subdivisions and agricultural building-exemption materials

208-220-2120

pandzadministrator@fcidaho.us

2 more officesSeptic permits · Roads & driveways

Septic permits

Southeastern Idaho Public Health — Franklin County Office

Local contact for the public health district that administers onsite septic permitting in Franklin County

(208) 852-0478

42 West 1st South, Preston, Idaho 83263

Roads & driveways

Franklin County Road and Bridge

County right-of-way and approach permit materials

208-852-0610

sarahl@fcidaho.us

561 West Oneida Preston, ID 83263

Contact details are copied from each office’s official page and were checked against it on October 10, 2026.

Do you need a building permit in Franklin County, Idaho?

Yes.

Yes. Franklin County requires a written building permit from the County Building Inspector before anyone erects or constructs a new building, structure or mobile home, and before remodeling that changes a building's outside dimensions¹. The county has adopted official building codes³. The county code sets the building permit fee at 1% of the assessed value of the proposed building, payable when the application is made¹. Idaho also requires permits whenever electrical, plumbing or HVAC work is performed, although a local jurisdiction may administer some of those programs⁸. Agricultural buildings are the important exception: Franklin County exempts them from its adopted building codes, but zoning placement requirements still apply³. Do not treat that agricultural exemption as a general exemption for a farmhouse, cabin or other residence. The county's Building Department publishes the building-permit materials and tells applicants to send permits to that department⁵.

Who is the Franklin County building department, and how do you reach it?

Franklin County's Building Department is at 561 West Oneida in Preston; call 208-221-6149 or email randallh@fcidaho.us.

Franklin County's Building Department is at 561 West Oneida in Preston; call 208-221-6149 or email randallh@fcidaho.us⁵. The department publishes building, mechanical and agricultural permit materials, along with a residential builders handbook and design criteria⁵. For land-use questions, contact Franklin County Planning & Zoning at 208-220-2120 or pandzadministrator@fcidaho.us³. The county's page does not publish a complete step-by-step process, and it states that a completed septic permit is required before a building permit can be issued⁵. The inspection sequence, certificate-of-occupancy process and other fees could not be confirmed. Ask the Building Department for the current application packet, fee total and required inspections before budgeting or scheduling construction.

Does Franklin County have zoning?

Yes.

Yes. Franklin County zoning applies to land throughout unincorporated Franklin County². Incorporated cities maintain their own plans, and city plans and zoning apply in an Area of City Impact only after annexation². A listing described as rural or agricultural therefore does not establish what may be built. Ask Planning & Zoning to identify the parcel's jurisdiction and district and confirm permitted uses, setbacks, minimum lot size, building height and subdivision rules. The county's website lists zoning guidelines, a 2025 comprehensive plan and an amended development code, but the opened page does not give district names or the exact unincorporated boundary³. Franklin County publishes its development code, subdivision application and agricultural building-exemption material through Planning & Zoning³. The agricultural building-code exemption does not waive zoning placement requirements³.

How do septic permits work in Franklin County?

Southeastern Idaho Public Health administers onsite septic permitting for Franklin County under Idaho's district system.

Southeastern Idaho Public Health administers onsite septic permitting for Franklin County under Idaho's district system^4,5,9. Start with the district's Franklin County office at 42 West 1st South in Preston, phone (208) 852-0478¹⁰. Every application needs an onsite evaluation, test holes at least 8-10 feet deep depending on soil type, a plot plan, a deed or tax notice and the fee⁴. The district's published sewage disposal permit fee is $850 for a basic or complex system, $3,000 for a large soil absorption system and $300 for a tank only; fees may change⁴. Only 5.3% of county soils avoid a severe limitation for a conventional drain field, so make septic feasibility a purchase contingency rather than assuming a standard system will work⁷. The public health district conducts the site evaluations and issues the septic permits, and no system may receive wastewater until the final installation inspection is complete^9,11. Franklin County requires the septic permit before issuing the building permit⁵.

Can you live in an RV or tiny home on your land in Franklin County?

Franklin County's rules for long-term RV living, temporary camping on private land and tiny-home occupancy could not be confirmed.

Franklin County's rules for long-term RV living, temporary camping on private land and tiny-home occupancy could not be confirmed. Zoning applies throughout unincorporated Franklin County, so ask Planning & Zoning whether the parcel permits the proposed dwelling or temporary occupancy^2,3. A manufactured home outside a park must generally be at least 20 feet wide and contain at least 900 square feet; a narrow replacement exception covers qualifying units in place by January 26, 1998⁶. The Building Inspector must inspect and certify the unit's bronze data plate before a building permit can issue, and the unit must meet county setbacks and other applicable rules⁶. Idaho also requires manufactured-home installation approval before occupancy¹².

How do you build a home in Franklin County, step by step?

Ask Franklin County Planning & Zoning to verify the parcel's zoning district, permitted dwelling type and dimensional standards.

Ask Franklin County Planning & Zoning to verify the parcel's zoning district, permitted dwelling type and dimensional standards^2,3.
Have Southeastern Idaho Public Health evaluate the site and issue the septic permit; Franklin County requires that permit before the building permit^4,5.
Confirm water. Before drilling a private well, obtain an Idaho Department of Water Resources drilling permit and use a licensed well driller¹³.
Apply to the Franklin County Building Department and confirm the current fee, plan requirements and inspection schedule^1,5.
Obtain separate permits for electrical, plumbing or HVAC work through the applicable Idaho or local program⁸.
If access crosses county right-of-way, ask Road and Bridge about its approach permit; a connection to state-highway right-of-way requires an Idaho Transportation Department encroachment permit^14,15.
Complete the required septic inspection before putting the system into service¹⁶.

What should you check before buying land in Franklin County?

Make septic feasibility the first physical-site check: only 5.3% of Franklin County soils avoid a severe limitation for a conventional drain field.

Make septic feasibility the first physical-site check: only 5.3% of Franklin County soils avoid a severe limitation for a conventional drain field⁷. Confirm zoning and legal access next, including whether the parcel supports the intended dwelling and whether a county approach permit or state-highway encroachment permit is needed^2,14,15. Franklin County evaluates all development for its location within the National Flood Insurance Program before approval and may limit density or intensity in floodplain and floodway areas². For a private well, budget for the required state drilling permit and licensed driller¹³. Franklin County has about 23.4 people per square mile, and 32.9% of its land is federally owned, so nearby public land does not establish private access or development rights⁷.

Watch-outs

A Franklin County agricultural building may be exempt from adopted building codes while still remaining subject to zoning placement requirements³.
Franklin County requires the septic permit to be completed before it will issue the building permit⁵.
Manufactured homes outside parks generally must be at least 20 feet wide and 900 square feet, and temporary permits last 12 months with one possible renewal⁶.
Long-term RV living, private-land camping, tiny-home occupancy and an owner-builder exemption could not be confirmed; ask Planning & Zoning and the Building Department before relying on any of them^3,5,17.

Sources

17 official pages, each quoted and re-checked · written October 10, 2026

Written October 10, 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.

Off-grid gear

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

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Compared with neighboring counties

Like all 6 of its neighbors, Franklin County requires a building permit for a home.

Rule	Franklin County	Bear Lake County	Bannock County	Oneida County	Caribou County	Power County	Bingham County
Building permit	Required	Required	Required	Required	Required	Required	Required
County zoning	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Septic permits	SIPH	Southeastern Idaho Public Health	Southeastern Idaho Public Health	Southeastern Idaho Public Health	SIPH	Southeastern Idaho Public Health	Southeastern Idaho Public Health

Answers from the rulebook for Franklin County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Franklin County rules

Building permitRequired
Erecting or constructing a new building, structure, or mobile home, and remodeling an existing building, structure, or mobile home where the outside dimensions are changed, within Franklin County.
- A written building permit must be obtained first from the County Building Inspector.
- Agricultural buildings are exempt from the county-adopted building codes but remain subject to zoning placement requirements.
- Industrial and commercial buildings whose owners certify in advance that they will create and fill five or more full-time positions within the succeeding 24 months may be exempt from International Building Code fees, but remain subject to the county building permit and site inspection fee requirements.
- The county Building Department states that a septic permit must be completed before a building permit can be issued.
building permit fee: 1% of assessed value of proposed building USD (payable when application is made for construction defined in § 150.015)
“No person, firm, or corporation shall here after erect or construct any new building, structure, or mobile home within the county without having first obtained a written building permit to do so from the County Building Inspector.”
§ 150.015 Building Permit Required ↗Re-checked Oct 10, 2026
Building code adoptedAdopted (with conditions)
International building codes administered by Franklin County.
- The county page labels the item Adoption of International Codes - Amended June 8, 2026; the specific code editions and amendments were not available in the opened official webpage.
“Adoption of International Codes - Amended June 8, 2026”
franklincountyidaho.org ↗Re-checked Oct 5, 2026
County-wide zoningPresent (with conditions)
Land-use designations and zoning in unincorporated Franklin County.
- Areas within an adopted Area of City Impact are subject to city plans and zoning only upon annexation pursuant to Idaho Code 67-6529.
“These future land designations apply to all lands located within unincorporated Franklin County. [...] The Franklin County Zoning and Development Code and zoning designations will be used to implement these land use designations.”
Franklin County Comprehensive Plan ↗Re-checked Oct 1, 2026
Local zoningVaries (with conditions)
Aggregate local zoning across unincorporated Franklin County and incorporated-city areas.
- The county code applies in the unincorporated area; city plans and zoning apply within adopted Areas of City Impact only upon annexation, and incorporated municipalities may administer their own rules.
“Policies are adopted for the unincorporated county, each city adopts and maintains their own plan.”
Franklin County Comprehensive Plan ↗Re-checked Oct 1, 2026
Zoning districtsPublished (with conditions)
County zoning-district information and related zoning materials.
- The official page lists Zoning Guidelines and an amended Development Code but does not provide the district names or the exact unincorporated boundary in the opened webpage.
“Zoning Guidelines Comprehensive Plan 2025 Development Code - Amended 2026 Manufactured Home Ordinance”
Planning & Zoning ↗Re-checked Oct 5, 2026
Minimum lot sizeDistrict specific (with conditions)
Base zoning districts in unincorporated Franklin County, including City Areas of Impact unless otherwise specifically negotiated and accepted by Franklin County.
- The Development Code applies to development of all land in unincorporated Franklin County, including a City Area of Impact, unless otherwise specifically negotiated and accepted by Franklin County.
- The AI minimum may be reduced to one-half acre if central water or central sewer is available.
- P/PS Public/Semi-Public has no minimum lot area in Table 9-2-1.
- Cluster lots may be smaller than the applicable district minimum but not below one acre, subject to community water and sewage-disposal provisions and the remaining conservation-subdivision standards.
- Multi-family development has a two-acre minimum lot size and a maximum density of one unit per one-half acre.
R-A Agricultural Residential minimum lot area: 10 acres · AI Rural Residential minimum lot area: 1 acre (May be reduced to 0.5 acre when central water or central sewer is available.) · R1 Residential One minimum lot area: 1 acre · R2 Residential Two minimum lot area: 2.5 acres · RC Recreation minimum lot area: 1 acre · C Commercial minimum lot area: 1 acre · I/E Industrial/Extraction minimum lot area: 1 acre · P/PS Public/Semi-Public minimum lot area: No Minimum · multifamily-development minimum lot size: 2 acres (Also subject to Code Chapter 8 and all other Development Code requirements.)
“P/PS Public/Semi-Public [...] No Minimum”
Franklin County Development Code — amended 2026 ↗Re-checked Nov 13, 2026
SetbacksDistrict specific (with conditions)
Base zoning districts in unincorporated Franklin County, including City Areas of Impact unless otherwise specifically negotiated and accepted by Franklin County.
- The Development Code applies to development of all land in unincorporated Franklin County, including a City Area of Impact, unless otherwise specifically negotiated and accepted by Franklin County.
- FEMA, groundwater/well-protection, high-nitrate, and Preston Airport overlays must comply with the base district and the referenced Code section.
- A development agreement may impose specific conditions and limitations.
- The Code states that the AI minimum lot size may be reduced to one-half acre when central water or central sewer is available.
- The Code separately states that arterial and collector front-yard and street-side setbacks in all residential districts are 100 feet from road centerline.
- The Code provides listed setback-reduction procedures and an additional five-foot-per-story side setback for multi-story structures, except single-family attached dwellings.
base-district front setback: 50 ft (R-A, AI, R1, R2, RC, C, and I/E districts.) · base-district rear setback: 10 ft (R-A, AI, R1, R2, RC, C, and I/E districts.) · base-district side setback: 10 ft (R-A, AI, R1, R2, RC, C, and I/E districts.) · base-district corner setback: 50 ft (R-A, AI, R1, R2, RC, C, and I/E districts.) · residential arterial and collector front-yard setback: 100 ft from road centerline (All residential zoning districts.) · residential arterial and collector street-side setback: 100 ft from road centerline (All residential zoning districts.)
“R1 Residential One 40 ft 50 ft 10 ft 10 ft 50 ft 1-acre”
Franklin County Development Code — amended 2026 ↗Re-checked Nov 13, 2026
Living in an RVLimited
Recreational vehicle parks, commercial campgrounds, and recreational areas in unincorporated Franklin County, including City Areas of Impact unless otherwise specifically negotiated and accepted by Franklin County.
- The Development Code applies to development of all land in unincorporated Franklin County, including a City Area of Impact, unless otherwise specifically negotiated and accepted by Franklin County.
- Private campgrounds and recreational uses by a landowner in the RC zone must adhere to applicable county, state, and federal regulations.
- A recreation area must be at least 10 acres and may have a maximum intensity of one unit per one-half acre.
- Facilities are seasonal and not intended for year-round occupation; the Code defines seasonal use here as April 1 through October 21.
- RVs must be fully licensed and ready for highway use, remain on wheels or jacking system, connect only through quick-disconnect utilities and security devices, and have no permanently attached additions.
- The applicant must demonstrate sufficient sewer and water capacity, including approvals from IDEQ and the State Health Department.
- One home or RV may be permanently placed for a caretaker only if current caretaker and legal-owner contact information is registered with the county.
- An RV or utility trailer may not be parked or stored on a county road for more than 24 hours, and may not be occupied or connected to utilities while parked on a county road.
minimum recreation area: >= 10 acres · maximum intensity of use: 1 unit per 0.5 acre · seasonal use period: April 1 to October 21 (Facilities are not intended for year-round occupation.) · county-road RV or utility-trailer parking/storage: <= 24 hours (The RV or trailer may not be occupied or connected to any utility while parked on a county road.)
“Recreation Vehicle Park /Campground. To allow for recreational vehicle (RV) parks, commercial campgrounds and/or recreational areas. To establish reasonable regulation concerning the operation of these activities in order to protect the health, safety and welfare of the public, which includes protecting the natural resources found in Franklin County and the associated amenities provided by these natural resources, including but not limited to surface and ground water, air, soils, native vegetation, aquatic and terrestrial wildlife and habitat, unique geologic features, topography and scenic views.”
Franklin County Development Code — amended 2026 ↗Re-checked Nov 13, 2026
Manufactured homesLimited
Manufactured homes installed outside manufactured-home parks in Franklin County.
- A building permit cannot issue until the Building Inspector inspects and certifies the bronze data plate.
- The unit must satisfy applicable county ordinances, county setbacks and other building ordinances, and Idaho statutes.
- Units outside parks must be at least 20 feet wide and 900 square feet, except qualifying units in place on or before January 26, 1998.
- A temporary permit may last 12 months and may be renewed once; the unit must then be removed.
minimum width: >= 20 feet (Units outside manufactured-home parks.) · minimum floor area: >= 900 square feet (Units outside manufactured-home parks; exception for qualifying pre-January 26, 1998 units.) · temporary permit duration: 12 months (May be renewed once.)
“All manufactured home units located or installed outside of manufactured home parks must be a minimum of 20 feet wide and contain a minimum of 900 square feet; provided however, such units which were in place on or before January 26, 1998, may be replaced or upgraded with equal or larger sized units that meet the requirements of division (B) above.”
§ 151.06 Manufactured Home Restrictions ↗Re-checked Oct 1, 2026
Who permits septicLocal (with conditions)
Individual and subsurface sewage disposal systems administered through Southeastern Idaho Public Health materials.
- The Franklin County Building Department links to the SIPH septic permit and requires that permit before a county building permit can be issued.
- Idaho statewide sewage-disposal rules also apply.
“Septic Permit must be completed before a Building Permit can be issued.”
Building Department ↗Re-checked Oct 5, 2026
Septic permitRequired
Onsite sewage disposal systems serving property in Franklin County within the health district.
- The Franklin County Building Department states that the septic permit must be completed before a county building permit can be issued.
- An onsite evaluation is required for all applications.
- The applicant must provide test holes at least 8-10 feet deep depending on soil type.
- The application requires a completed plot plan, deed or tax notice, and applicable fee.
speculative site evaluation fee: 300 USD · full site evaluation and permit fee if site is suitable: 925 USD · test-hole depth: 8-10 feet (depending on soil type)
“INFORMATION REQUIRED TO APPLY FOR A SEPTIC PERMIT”
Building Department ↗Re-checked Oct 5, 2026
Septic inspectionRequired
Septic installations in Franklin County administered by Southeastern Idaho Public Health as the applicable public health district.
- The Idaho Department of Environmental Quality states that public health districts administer the statewide septic rules under an MOU with DEQ.
- The DEQ page describes inspections for individual systems by the public health district and for large soil absorption systems by the public health district and DEQ.
- System type, site conditions, and permit requirements may impose additional requirements.
“Idaho’s seven public health districts administer these rules under a memorandum of understanding (MOU) with DEQ. The public health districts conduct site evaluations, issue septic system permits, inspect installations, and assist with property-specific questions about permitting, existing systems, and permit records.”
Septic and Septage ↗Re-checked Oct 5, 2026
Agricultural exemptionAvailable (with conditions)
Agricultural exemptions from county building permits.
- The official page identifies an Ag Exemption from Building Permit form; the eligibility conditions were not stated on the opened webpage and require review of the form or ordinance.
“Ag Exemption from Building Permit Adoption of International Codes - Amended June 8, 2026”
franklincountyidaho.org ↗Re-checked Oct 5, 2026
Building in a floodplainLimited
Development located in or potentially affected by floodplain or floodway areas in Franklin County.
- All development is evaluated for location within the National Flood Insurance Program before approval.
- The county may limit density and intensity within the floodplain and floodway.
- The county will implement a floodplain/floodway overlay designation.
“All development will be evaluated as to its location within the National Flood insurance program prior to approval. [...] The County reserves the right to limit the density and intensity of uses within the floodplain and floodway.”
Franklin County Comprehensive Plan ↗Re-checked Oct 1, 2026
Permit feesPublished (with conditions)
Published septic-permit fees in the Southeastern Idaho Public Health materials.
- The page states that fees are subject to change.
sewage disposal permit: basic or complex system: 850 USD · sewage disposal permit: large soil absorption system: 3000 USD · sewage disposal permit: tank only: 300 USD · speculative site evaluation: 300 USD · septic permit renewal: 40 USD
“Sewage Disposal Permit: Basic or Complex System | $850 Sewage Disposal Permit: Large Soil Absorption System | $3,000 Sewage Disposal Permit: Tank Only | $300 Speculative Site Evaluation | $300 Septic Permit Renewal | $40”
Septic Permits ↗Re-checked Oct 5, 2026
Permit processPartial
The Franklin County Building Department's published permit materials and prerequisite for county building permits.
- The page identifies the Building Department as the recipient for permits and provides its Preston address.
- The page lists Agricultural, Building, Mechanical, and related permit documents.
- A completed septic permit is required before a Building Permit can be issued.
- The page does not publish a complete end-to-end permit process, including all application, review, inspection, fee, or approval steps.
“Please remit permits to Randy Henrie at the Building Department. [...] Septic Permit must be completed before a Building Permit can be issued.”
Building Department ↗Re-checked Oct 5, 2026
One more reviewed finding on this topic
- Partial — County building-permit process and prerequisite documentation.
  “Septic Permit must be completed before a Building Permit can be issued.”
  Building Department ↗Re-checked Oct 5, 2026

Idaho rules that apply here

Owner-builder exemptionConditional
Homeowners personally performing plumbing work on their own residential premises in Idaho.
- The homeowner must own the residential property and personally perform the permitted work.
- The homeowner permit is valid only for a primary or secondary residence and associated outbuildings.
- Associated outbuildings must not be used for commercial purposes or rented by a tenant.
- The homeowner must accept responsibility for all work performed.
- All work must be inspected by the Division of Occupational and Professional Licensing.
- A plumbing permit must be obtained by application to the Division.
- The application must be submitted with payment.
- The application form states that an additional $65 fee may be assessed if the location is not clearly provided by directions or an attached map.
- The application was revised 8/17/2022; this revision date is not treated as an effective date.
unclear-location fee: 65 USD (May be assessed if the location is not clearly given by directions or an attached map.)
“I certify that I am the owner of the residential property and will personally perform the work covered by this permit.”
Homeowner Plumbing Permit Application ↗Re-checked Oct 5, 2026
4 more reviewed findings on this topic
- Available — An owner performing their own construction work on the owner's own land in Idaho.
  “A: Any person who engages in a construction job with a dollar amount exceeding $2000.00 (materials & labor) and is not otherwise exempt (The exemptions are listed below); [...] Owners: Owners who do their own work on their own land and do not intend to sell the property within 12 months are exempt from registration.”
  Frequently Asked Questions (FAQ) - Division of Occupational and Professional Licenses ↗Re-checked Oct 3, 2026
- Conditional — An Idaho homeowner undertaking construction or trade work for which a state-administered permit process applies.
  “Public (Homeowners Only) [...] *Public: “Homeowner” is pre-selected. [...] Once payment is processed, you may choose “Request Inspection” and/or “Print Permit””
  How To Purchase a Trade Permit ↗Re-checked Oct 3, 2026
- Conditional — Owners performing construction work on their own land in Idaho under the state contractor-registration system.
  “Owners who do their own work on their own land and do not intend to sell the property within 12 months are exempt from registration.”
  Frequently Asked Questions (FAQ) - Division of Occupational and Professional Licenses ↗Re-checked Oct 5, 2026
- Conditional — Homeowners personally performing electrical work on a primary or secondary residence and related outbuildings in Idaho.
  “Homeowners may purchase a permit only when they themselves are doing electrical work on their primary or secondary residence and/or related outbuildings.”
  dopl.idaho.gov ↗Re-checked Oct 5, 2026
InspectionsRequired
All manufactured-home installations in Idaho before the manufactured home is occupied.
- The inspection and approval are performed by DOPL or the authority having jurisdiction.
- Inspection and approval must occur before occupancy.
“All installations must be inspected and approved by the Idaho Division of Occupational and Professional Licenses or the authority having jurisdiction before the manufactured home is occupied.”
Building Archives - Division of Occupational and Professional Licenses ↗Re-checked Sep 11, 2026
Camping on your landLimited
Camping or parking a vehicle or trailer on Idaho Fish and Game Wildlife Management Areas and access sites separate from a WMA.
- The restriction applies in areas posted against camping or parking.
- Leaving an unattended camp, vehicle, or trailer for more than 48 hours is prohibited without authorization.
- Camping or parking for more than 10 days during any 30-day period on one WMA or one separate access site is prohibited without authorization.
- The rule permits authorization by the Commission, Director, Regional Supervisor, or designee.
unattended duration: > 48 hours (Unless specifically authorized by the Commission, Director, Regional Supervisor, or designee.) · camping or parking duration: > 10 days during any 30-day period per WMA or separate access site (Unless specifically authorized by the Commission, Director, Regional Supervisor, or designee.)
“camp or park a vehicle or trailer for more than ten (10) days during any thirty (30) day period”
Public Use of Department Lands and Access Areas ↗Re-checked Sep 11, 2026
Accessory dwellingsLimited
Accessory dwelling units for Idaho DEQ wastewater-flow and septic-system sizing purposes; this claim does not establish statewide zoning permission.
- An ADU is sized as a single-family dwelling for the cited wastewater-flow guidance.
- An ADU may combine flows with another structure into one system.
- Any common septic tank must be large enough to hold the required capacity from both structures.
- Local land-use, building, and septic authorities may impose additional requirements.
wastewater flow basis: single-family dwelling
“Size as a single family dwelling. Can combine with another structure's flows into one system”
Idaho DEQ - Uncommon Wastewater Flows ↗Re-checked Sep 11, 2026
Off-grid sanitationLimited
Installing, modifying, repairing or expanding individual or subsurface sewage disposal systems (septic) anywhere in Idaho, including off-grid homes
- A valid installation permit is required before any person modifies, repairs, expands or installs an individual or subsurface sewage disposal system, except as listed in subsection 005.02.
- Exceptions (005.02): portable nondischarging systems may be installed as temporary blackwaste or wastewater systems if properly maintained and of a design approved by the director; repairs for clogged or broken solid piping or electrical/mechanical malfunctions are allowed without a permit, but repairs may not expand the system unless authorized by the director.
- Excepted activities remain subject to all other relevant rules and regulations.
- Where this rule conflicts with state or local zoning, building, fire, safety or health regulation, the provision that in the director's judgment sets the higher health and safety standard prevails.
- Permit becomes invalid if construction is not completed and approved within two years of issuance unless otherwise stated; may be renewed at director's discretion.
- Director may deny where public or central wastewater treatment facilities are reasonably accessible.
- Permit fee is set under IDAPA 58.01.14.
- Rules are administered through the health districts under DEQ; the director may require operation, maintenance and monitoring conditions in the permit.
installation permit validity: 2 years (unless otherwise stated on the application or permit; renewable at director's discretion)
“01. permit required. except as specified in subsection 005.02 no person may modify, repair or expand or install any individual or subsurface sewage disposal system within the state of idaho unless there is a valid installation permit authorizing that activity.”
IDAPA 58.01.03 - Individual/Subsurface Sewage Disposal Rules and Rules for Cleaning of Septic Tanks (current) ↗Re-checked Nov 6, 2026
Well permitRequired
Construction or drilling of wells in Idaho, including domestic wells.
- Before drilling, the well owner or driller must obtain a drilling permit from IDWR.
- All wells must be constructed by a well driller with a valid IDWR license.
- The separate water-right permit exemption for domestic purposes does not eliminate the drilling-permit requirement.
- For new diversions in qualifying subdivisions filed on or after July 1, 2025, a water-right permit is required in a moratorium area, critical groundwater area, or groundwater management area, except for in-home uses and watering livestock.
- Well construction rules apply to wells and other artificial openings more than 18 vertical feet below land surface.
well depth threshold: > 18 vertical feet below land surface (The cited well-construction rules describe covered wells and artificial openings.) · subdivision application date: >= 2025-07-01 (Applies to qualifying new diversions described in Idaho Code § 42-227(4).)
“Prior to drilling a well, the well owner or well driller must first obtain a drilling permit from IDWR.”
Wells Overview ↗Re-checked Sep 11, 2026
Mandatory utility hookupConditional
Proposed individual or subsurface sewage disposal systems where public or central wastewater treatment facilities may be available.
- The Director may deny a septic permit when public or central wastewater treatment facilities are reasonably accessible.
- The cited rule does not establish a universal statewide requirement to connect every property to public sewer.
- Subsurface septic discharge remains an identified onsite disposal method.
“Public or central wastewater treatment facilities are reasonably accessible.”
IDAPA 58.01.03 Individual/Subsurface Sewage Disposal Rules ↗Re-checked Sep 11, 2026
Shed and accessory-building permit exemptionAvailable (with conditions)
One-story detached accessory structures regulated under the state-adopted 2018 Idaho Residential Code for one- and two-family dwellings.
- The Idaho Building Code Board's current rule adopts the 2018 International Residential Code, Parts I, II, III, and IX, with Idaho amendments, for one- and two-family dwellings.
- The cited exemption is from the residential-code building-permit requirement; it does not itself authorize work that violates local land-use, zoning, utility, trade-permit, or other requirements.
- Building-code and placement-site jurisdiction may be exercised by the applicable city or county.
maximum floor area for one-story detached accessory structure permit exemption: <= 200 square feet (Applies to the residential-code exemption for one-story detached accessory structures.)
“One-story detached accessory structures, provided that the floor area does not exceed 200 square feet.”
IDAPA 24.39.30 — Rules of Building Safety (Building Code Rules) ↗Re-checked Nov 4, 2026
Driveway accessRequired
Private and public driveways or streets connecting to Idaho state highway right-of-way.
- An ITD encroachment permit is required for private and public approaches, including driveways and streets.
- No activity may occur on state highway rights-of-way until the Department or a delegated local highway agency issues an approved permit, except emergency approval affecting highway operations and motorist safety may precede processing.
- A Traffic Impact Study may be required for new or expanded development seeking direct access to a state highway when the stated thresholds are met, unless waived by the District Engineer.
peak-hour trips for possible TIS requirement: >= 100 new trips (unless waived by the District Engineer) · daily traffic for possible TIS requirement: >= 1000 vehicles per day (unless waived by the District Engineer)
“Encroachment permits approved by the Department are required for private and public approaches (driveways and streets), utilities and other miscellaneous encroachments.”
Types of Right-of-Way Encroachment Permits ↗Re-checked Sep 11, 2026
Campground & park staysLimited
Temporary camping in Idaho State Parks administered by the Idaho Department of Parks and Recreation.
- Camping is permitted only in designated areas.
- Stays are limited to 14 nights in a 30-day period; the same page's FAQ separately states a 15-day limit, creating an unresolved internal discrepancy.
- Individual-site occupancy is limited to one family unit or no more than 8 persons unless otherwise specified; companion-site and site-design restrictions apply.
- Camping is not permitted on beaches, parking lots, or day-use facilities.
- Check-in is at 2 p.m. for campsites and checkout is at 1 p.m.; late checkouts may incur additional fees unless prior arrangements have been made.
state-park stay limit: 14 nights in 30 days (FAQ on the same page states 15 days in any 30-day period) · individual-site people limit: <= 8 people (one family unit or site-specific limits may apply)
“Camping is permitted only in designated areas. [...] Stays are limited to 14 nights in a 30-day period.”
Camping | Department of Parks and Recreation ↗Re-checked Oct 1, 2026
county zoning authorityGeneral
Idaho counties adopting zoning for unincorporated areas through their boards of county commissioners.
- A board of county commissioners is a governing board and may exercise the powers authorized by the Local Land Use Planning Act.
- The county board's powers under the chapter apply to the unincorporated area of the county.
- Zoning must be adopted, amended, or repealed by ordinance using the notice and hearing procedures in Idaho Code § 67-6509.
- Zoning districts must conform to the adopted comprehensive plan.
- Within zoning districts, standards may regulate or restrict building height, number of stories, size, construction, reconstruction, alteration, repair or use of buildings and structures; lot occupancy; courts, yards and open spaces; population density; and building and structure location and use.
- Standards must be uniform for each class or kind of building throughout each district, but may differ between districts.
- Overlay zoning districts require clear and objective standards and must not constitute a regulatory taking under Idaho or federal law.
“The powers of the board of county commissioners conferred by this chapter shall apply to the unincorporated area of the county.”
Idaho Code § 67-6504 — Planning and zoning commission ↗Re-checked Oct 5, 2026
county building authorityGeneral
Idaho counties' authority to adopt and enforce building codes and require permits for residential construction in unincorporated areas when the county operates a building-code enforcement program.
- The statute defines local government as any city or county of Idaho.
- A local government that had not previously implemented a code-enforcement program may elect to implement one by ordinance evidencing its intent to do so.
- Construction in a local-government jurisdiction enforcing building codes requires a permit under the applicable local ordinance.
- A local government issuing permits and performing enforcement must adopt the specified state-adopted codes and may amend them only within the limits stated in Idaho Code § 39-4116(4).
- Local amendments must generally provide at least an equivalent level of protection; accessibility amendments are restricted, and additional residential-code amendments require the statutory good-cause, necessity, ordinance, public-hearing, publication, and notice procedures.
- Single-family homes and multiple-family dwellings up to two units are exempt from automatic fire-sprinkler requirements in the enumerated codes.
- Agricultural buildings must be exempted; a county may issue farm-building permits only for road setbacks and utility easements, at no more than actual issuance cost.
- Permits are governed by the laws in effect when the application is received.
- The state division retains jurisdiction for in-plant inspections and installation standards for manufactured or mobile homes and for in-plant inspections and enforcement of modular-building and commercial-coach construction standards.
“"Local government" means any city or county of this state.”
Idaho Building Code Act statutes ↗Re-checked Oct 5, 2026

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

Certificate of occupancy — Certificates of occupancy in Franklin County.
Minimum dwelling size — Minimum floor area for a dwelling in unincorporated Franklin County.
Lot coverage — Lot-coverage requirements.
Building height — Building-height requirements.
Tiny homes — Tiny-home occupancy on private land in unincorporated Franklin County.

2 more unanswered

Subdividing land
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.

Water rights & wells in Franklin County

Whether a new home can legally get its own water here — the sub-state groundwater regime, from Idaho’s water agency.

Actively managed

This basin is under active state management — new water use is scrutinized, though a domestic well is usually still allowed.

Household wellExempt — no permit or water right

Groundwater for domestic purposes up to 13,000 gpd is exempt from permitting; critical-area and moratorium closures generally target new PERMITTED (non-exempt) appropriations, so a household can still drill a domestic-exempt well even inside a critical groundwater area.

Limit: 13,000 gpd (homes, stockwater, irrigation of ≤0.5 acre) under Idaho Code 42-227

Idaho Dept of Water Resources — Domestic Exemption ↗

Bear River Ground Water Management Areapartial of county
Designated 2001; new appropriations must demonstrate sufficient supply without injuring senior rights. Domestic-exempt wells allowed.
Idaho Dept of Water Resources — Designated Ground Water Management Areas ↗
Malad Valley Ground Water Management Areapartial of county
Designated 2015; temporary moratorium on new non-exempt appropriations extended through 2027. Domestic-exempt wells allowed.
Idaho Dept of Water Resources — Designated Ground Water Management Areas ↗

Prior-appropriation state (first in time, first in right). Groundwater rules change and basin boundaries follow the aquifer, not the county line — confirm current well and appropriation rules with the Idaho state water agency before you buy or drill.Groundwater governance as of Jul 2026, cited to each administering agency.

Living off-grid in Franklin County, Idaho

Is Franklin County a good place to live off-grid or homestead?

Franklin County scores 64/100 on the Bolthole Index, a strong county profile. Its strengths: a stronger property-autonomy legal backdrop and manageable long-term carry cost. Watch-outs: more administrative friction around building and land use.

How much does land cost in Franklin County, Idaho?

Land in Franklin County runs about $3,278 per acre, based on the latest county data.

What is the water situation in Franklin County?

Franklin County gets about 23.1" of rain a year, with severe drought in roughly 13.5% of years. On water rights, Franklin County lies in the Bear River Ground Water Management Area — Designated 2001; new appropriations must demonstrate sufficient supply without injuring senior rights. Domestic-exempt wells allowed..

How remote is Franklin County?

A representative private-land location has about 32,819 people within a 30-minute drive and 1,971,738 within two hours. The road-network catchments count population across county lines and clusters of smaller cities; straight-line radius values remain available as a comparison.

Building permits, zoning and land rules in Franklin County, Idaho