Bolthole Index

Twin Falls County, Idaho

Building permits, zoning and septic rules in Hansen, Idaho

Hansen, Idaho requires a building permit from the City building inspector before covered construction, alteration or demolition.1 Hansen sets its own zoning inside city limits in Twin Falls County.2 Private sewage systems require a City permit where public sewer is unavailable, alongside Idaho health-district requirements administered locally by South Central Public Health District.345

At a glance

Building permit
Required from the City building inspector1
Zoning
Hansen administers city zoning2
Private sewage
City permit and $100 permit/inspection fee; health requirements also apply3
R-1 setbacks
Front 10 feet, side 7 feet, rear 20 feet6
R-1 lot coverage
Dwellings and accessory buildings may occupy no more than 60%7
Agricultural buildings
Exempt from adopted building codes; zoning placement still applies8
Owner-builder
State contractor-registration exemption is conditional; building permits still apply91

Who to call

Building permits

Hansen City Hall / City Clerk

Contact point to request the City building inspector, building application, fee schedule and zoning assistance.

Septic permits

South Central Public Health District — Twin Falls Main Office

Health-district septic permitting and property-specific land/septic questions for Twin Falls County, including Hansen.

(208) 737-5900

[email protected]

1020 Washington Street North

Contact details are copied from each office’s official page and were checked against it on October 12, 2026.

Off-grid gear

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

These are affiliate links — we may earn a commission, at no cost to you. As an Amazon Associate, Bolthole Index earns from qualifying purchases.

Do you need a building permit in Hansen, Idaho?

Hansen requires a City building permit before erecting, constructing, enlarging, altering, repairing, moving, converting or demolishing a building or structure.1 Hansen adopts building codes as adopted by Idaho or the Idaho Building Code Board, including successive versions when the board makes them effective.10 Agricultural buildings are exempt from the adopted building codes, but Hansen zoning placement requirements still apply.8 An agricultural-code exemption therefore does not remove the need to resolve where the building may sit.8

Who issues Hansen building permits, and how do you apply?

The Hansen City building inspector issues building permits after reviewing a written application on the inspector’s form for acceptability under the International Building Code.11 Request the application form from Hansen’s City building inspector before preparing a submission.11 Hansen building-permit fees follow a schedule established by City Council resolution; ask the City for the current schedule before budgeting the project.12 The City building permit and applicable payment must be in place before covered construction begins.11

Does Hansen have zoning, and what are the setbacks?

Hansen administers its own zoning inside city limits, so begin with the City when confirming a parcel’s zoning district.2 In Hansen’s R-1 district, primary dwelling setbacks are at least 10 feet from the front property line, 7 feet from the side and 20 feet from the rear.6 Corner and double-frontage lots require the front setback on both streets.6 R-1 dwellings and accessory buildings together may occupy no more than 60% of the lot.7 Detached accessory buildings have separate placement requirements, including separation from the main building.6

How do septic permits work inside Hansen?

Hansen allows private sewage disposal where public sanitary sewer is unavailable, with a written City permit required before construction.3 The City application must include plans, specifications and other requested information, and the permit and inspection fee is $100 when filed.3 Idaho also requires a valid installation permit for installing, modifying, expanding or repairing a septic system unless a specified state exception applies.13 South Central Public Health District serves Twin Falls County and accepts property-specific septic permitting questions.5 Arrange both City and health-district approvals; City approval does not displace additional state requirements.144

Can you live in an RV or tiny home on land in Hansen?

We could not confirm Hansen’s rules for living in an RV, temporary camping, tiny-home occupancy or accessory dwellings; ask the City to evaluate the proposed use before buying a structure or relying on temporary housing.15 Hansen’s building-permit requirement covers constructing, moving and converting buildings or structures, so a small building still needs review under the applicable City requirements.1 For a manufactured home, Idaho requires installation inspection and approval by DOPL or the authority having jurisdiction before occupancy.16

What are the steps for building a home in Hansen?

  1. Ask Hansen to confirm the zoning district and review the proposed building placement; apply the R-1 setbacks only if the parcel is in that district.26
  2. Resolve sewer availability with the City; private sewage disposal is conditional on public sewer being unavailable.17
  3. Submit the City building inspector’s written application and pay the applicable building-permit fee before covered work starts.11
  4. Arrange electrical, plumbing and HVAC permits with the applicable authority; Idaho trade-permit administration varies by location.18
  5. For private sewage, notify Hansen before underground work is covered and when ready for final inspection, alongside the required health-district inspection.1920

What should you check before buying land in Hansen?

Confirm whether the parcel is inside Hansen city limits before choosing the building and zoning office; use the Twin Falls County guide for land outside the city, where county zoning applies to unincorporated territory.221 Hansen requires direct public-sewer connection when sewer becomes available to property using private sewage disposal, with the old facility abandoned and filled.17 If a private well is proposed, Idaho requires an IDWR drilling permit before drilling and a licensed well driller.22 Land subdivision inside Hansen also requires City Council approval.23

Watch-outs

  • Hansen’s $100 private-sewage permit and inspection fee is a City fee; additional state and health-district requirements still apply.3
  • We could not confirm Hansen’s general building-inspection schedule, certificate-of-occupancy requirements or floodplain-development rules; request those answers from the City before committing to construction.15
  • Idaho’s owner-builder contractor-registration exemption applies to owners doing their own work on their own land who do not intend to sell within 12 months; Hansen’s building-permit requirement still applies.91

Sources

  1. 9-1-2: Building Permits (Hansen), quoted and re-checked
  2. Ordinance No. 223 (Hansen), quoted and re-checked
  3. 8-3A-18: Private Sewer Permitted; Regulations (Hansen), quoted and re-checked
  4. Septic and Septage (Idaho statewide rule), quoted and re-checked
  5. South Central Public Health District — Twin Falls Main Office (phd5.idaho.gov)
  6. 10-4B-8: Yards; Setbacks (Hansen), quoted and re-checked
  7. 10-4B-6: Lot Area and Occupancy (Hansen), quoted and re-checked
  8. 9-1-1: Codes Adopted (Hansen), quoted and re-checked
  9. Frequently Asked Questions (FAQ) - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
  10. 9-1-1: Codes Adopted (Hansen), quoted and re-checked
  11. 9-1-2: Building Permits (Hansen), quoted and re-checked
  12. 9-1-2: Building Permits (Hansen), quoted and re-checked
  13. IDAPA 58.01.03 – Individual/Subsurface Sewage Disposal Rules and Rules for Cleaning of Septic Tanks (Idaho statewide rule), quoted and re-checked
  14. 8-3A-18: Private Sewer Permitted; Regulations (Hansen), quoted and re-checked
  15. Hansen City Hall / City Clerk (cityofhansen.org)
  16. Building Archives - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
  17. 8-3A-18: Private Sewer Permitted; Regulations (Hansen), quoted and re-checked
  18. Frequently Asked Questions (FAQs) - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
  19. 8-3A-18: Private Sewer Permitted; Regulations (Hansen), quoted and re-checked
  20. IDAPA 58.01.03 Individual/Subsurface Sewage Disposal Rules (Idaho statewide rule), quoted and re-checked
  21. Twin Falls County Zoning Code 2022 (2026 county census)
  22. Wells Overview (Idaho statewide rule), quoted and re-checked
  23. 10-6A-1 through 10-6A-5: Subdivision Regulations (Hansen), quoted and re-checked

Written October 12, 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 Hansen

Hansen’s own rules

  • Building permitRequired

    Erecting, constructing, enlarging, altering, repairing, moving, converting, or demolishing any building or structure inside Hansen city.

    • A building permit must be obtained first from the City building inspector.
    • The appropriate fee must be paid under the fee schedule established by City Council resolution.
    “without first obtaining a building permit”
  • Building code adoptedAdopted (with conditions)

    Building construction inside Hansen city.

    • The City adopts the listed codes as adopted by Idaho or the Idaho Building Code Board.
    • Successive versions are deemed adopted when made effective by the Idaho Building Code Board.
    • Agricultural buildings are exempt from the adopted Building Codes but remain subject to zoning placement requirements.
    “are adopted as the official Building Codes of the City”
  • Local zoningPresent

    Land inside Hansen city limits; Hansen adopts and administers zoning regulations.

    • The code is hosted as the City of Hansen Code of Ordinances; Ordinance 223 documents a city zoning-map amendment.
    “CHANGING THE ZONING CLASSIFICATION OF REAL PROPERTY”
  • SetbacksSpecified

    Primary dwellings and detached accessory buildings in the R-1 district inside Hansen city.

    • Double-frontage and corner lots require the 10-foot front yard on both streets.
    • Accessory buildings are prohibited in the front yard and must be 20 feet from property lines on other street frontages.
    • Detached accessory buildings must be at least 3 feet from side and rear property lines and 10 feet from the main building.

    R-1 front setback: >= 10 feet · R-1 side setback: >= 7 feet · R-1 rear setback: >= 20 feet

    “The front building line shall not be closer than ten feet (10') to the front property line. [...] The side building line shall not be closer than seven feet (7') to the side property line. [...] The rear building line shall not be closer than twenty feet (20') to the rear property line.”
  • Lot coverageSpecified

    Dwellings, including accessory buildings, in the R-1 district inside Hansen city.

    R-1 maximum lot occupancy: <= 60 percent

    “shall occupy more than sixty percent (60%) of a lot”
  • Who permits septicMixed (with conditions)

    Private sewage disposal systems inside Hansen city.

    • Hansen requires a City permit and City inspection.
    • System type, capacity, location, and layout must comply with Idaho Department of Health and Welfare and/or Central District Health Department rules and recommendations.
    • Additional state requirements may apply.
    “Before commencement of construction of a private sewage disposal system, the owner shall first obtain a written permit from the city. [...] The city shall be allowed to inspect the work at any stage of construction [...] The type, capacities, location and layout of a private sewage disposal system shall comply with all of the rules and regulations and recommendations of the Idaho department of health and welfare and/or the central district health department. [...] No statement contained in this section shall be construed to interfere with any additional requirements that may be imposed by the department of health and welfare of the state.”
  • Septic permitRequired

    Construction of a private sewage disposal system inside Hansen city where public sanitary sewer is unavailable.

    • A written City permit is required before construction.
    • Application must use a City form and include plans, specifications, and other information the City requires.
    • A $100 permit and inspection fee is due when the application is filed.
    • Health-department and state requirements also apply.

    permit and inspection fee: 100 USD (paid at application filing)

    “Where a public sanitary sewer is not available under the provisions of this article, the building sewer shall be connected to a private sewage disposal system complying with the provisions of this article and in accordance with the following special provisions: [...] Before commencement of construction of a private sewage disposal system, the owner shall first obtain a written permit from the city. The application for such permit shall be made on a form furnished by the city, which the applicant shall supplement by plans, specifications and other information as may be deemed necessary by the city. A permit and inspection fee of one hundred dollars ($100.00) shall be paid to the city at the time the application is filed.”
  • Septic inspectionRequired

    Private sewage disposal system installation inside Hansen city.

    • The installation must be completed to the City's satisfaction.
    • The City may inspect at any construction stage.
    • The applicant must notify the City before underground work is covered and when ready for final inspection.
    • Inspection is due within 72 hours after notice, excluding Saturdays, Sundays, and holidays.

    inspection response time: 72 hours (Saturdays, Sundays, and holidays excluded)

    “A permit for a private sewage disposal system shall not be effective until the installation is completed to the satisfaction of the city. The city shall be allowed to inspect the work at any stage of construction and, in any event, the applicant for the permit shall notify the city when the work is ready for final inspection and before any underground works are covered. The inspection shall be made by the city within seventy two (72) hours after receipt of notice from the applicant, Saturdays, Sundays and holidays being excluded in calculating the elapsed time.”
  • Off-grid sanitationLimited

    Private sewage disposal systems inside Hansen city.

    • Allowed only where public sanitary sewer is unavailable.
    • City permit, $100 fee, City inspection, and state/Central District Health Department requirements apply.
    • Connection to public sewer becomes mandatory when available.
    “Where a public sanitary sewer is not available”
  • Mandatory utility hookupConditional

    New or existing premises inside Hansen city using private sewage disposal.

    • Where public sanitary sewer is unavailable, private sewage disposal is allowed subject to City and health requirements.
    • When public sewer becomes available, direct connection is required and the septic tank, cesspool, or similar facility must be abandoned and filled with suitable material.
    “Where a public sanitary sewer is not available under the provisions of this article, the building sewer shall be connected to a private sewage disposal system complying with the provisions of this article [...] At such time as a public sewer becomes available to property served by a private sewage disposal system, a direct connection shall be made to the public sewer in compliance with this article, and any septic tank, cesspool or similar private sewage disposal facilities shall be abandoned and filled with suitable material.”
  • Agricultural exemptionAvailable (with conditions)

    Agricultural buildings inside Hansen city.

    • Agricultural buildings are exempt from the City-adopted Building Codes.
    • They remain subject to zoning placement requirements.
    “Agricultural buildings are exempt from the Building Codes adopted herein”
  • Subdividing landRegulated (with conditions)

    Subdivision of land inside Hansen city limits.

    • All subdivisions must be submitted for City Council approval and comply with Chapter 6.
    • The chapter also applies within one mile outside city limits and the City's area of impact, but this claim concerns land inside city limits.
    • More restrictive laws, regulations, ordinances, or resolutions control where there is a conflict.
    “All subdivisions as defined in chapter 3 of this title shall be submitted for approval”
  • Permit feesVariable (with conditions)

    City building permits inside Hansen city.

    • The applicable fee is determined under a building-permit fee schedule established by City Council resolution.
    • The opened code does not state the current fee amount.
    “fee schedule which shall be established by resolution”
  • Permit processPublished (with conditions)

    Building-permit applications inside Hansen city.

    • The applicant must file a written application on the form furnished by the City building inspector.
    • The building inspector determines acceptability under the International Building Code and issues or denies the application.
    • A permit and applicable fee are required before covered construction activity begins.
    “To apply for a permit, the applicant shall first file an application therefor in writing on a form furnished for the purpose by the City building inspector, who shall determine the acceptability of the request in conformance with the International Building Code, and who shall thereupon issue or deny the application.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Hansen or Twin Falls County directly.

  • Owner-builder exemption — Owner-builder exemptions from building permits or inspections inside Hansen city.
  • Inspections — Building inspections for construction inside Hansen city.
  • Certificate of occupancy — Certificates of occupancy for buildings inside Hansen city.
  • Minimum dwelling size — Residential dwellings inside Hansen city.
  • Building height — Buildings inside Hansen city.
7 more unanswered
  • Living in an RV
  • Camping on your land
  • Tiny homes
  • Accessory dwellings
  • Well permit
  • 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 Hansen publishes no rule on the point, not that none exists. Twin Falls County’s page lists the county offices to call.

← All of Twin Falls County: county rules, score and offices