County Building Permits
Franklin County, ID - 2026 Building Permit Guide
How to apply for a building permit in unincorporated Franklin County, Idaho. Permit authority, application steps, fees, and inspection requirements.
Permit Authority
All properties in unincorporated Franklin County areas not within incorporated city limits.
- Department
- Franklin County Building Inspector
- Address
- Franklin County, Preston, ID
- Phone
- (208) 220-2120
Application Process
- Obtain septic permit from Southeast Idaho Public Health District before proceeding.
- Submit completed building permit application with required documentation to Franklin County Building Inspector.
- County reviews application for completeness and compliance with Idaho Building Code (2018 IBC) and Idaho Residential Code (2018 IRC).
- Pay required permit fees upon approval.
- Receive permit issuance and commence construction.
Typical processing time: Minimum 30 days from complete application submission
General Requirements
Building permits are required for residential and commercial construction in unincorporated Franklin County.
Required Documents
- Completed building permit application
- Construction plans (site plans, elevations, structural details)
- Proof of septic permit approval from Southeast Idaho Public Health District
- Any required engineering or design documentation
- Building code
- Idaho Building Code (2018 IBC) and Idaho Residential Code (2018 IRC) with state amendments.
- Contractor requirements
- Contractors performing work on projects of $2,000 or more in value must be registered with the Idaho Contractors Board. Proof of workers' compensation and general liability insurance ($300,000+ single limit) required.
Fees
- Payment note
- Contact Franklin County Building Department at (208) 220-2120 for current residential and commercial fee rates. Fees typically based on project valuation or square footage.
Work That Does NOT Require a Permit
Contact the Franklin County Building Inspector to confirm whether your project requires a permit before starting work.
Inspections
How to Schedule
- (208) 220-2120 (phone)
Additional Resources
- Building code: Idaho Building Code (2018 IBC) and Idaho Residential Code (2018 IRC) with state amendments.
- Verify contractor license: Idaho Contractors Board Registration
- Idaho Division of Building Safety (DOPL)
- Southeast Idaho Public Health District — Septic Permits
- Idaho Department of Environmental Quality — Septic and Septage
- License lookup guide: Idaho Contractor License Requirements
- Contract template: Idaho Homeowner-Contractor Agreement
- Idaho hub: Idaho Contractor License & Permit Hub
Information on this page was last verified: March 2026. Permit rules and fees change — confirm current requirements directly with the Franklin County Building Inspector before applying.
Frequently Asked Questions
Franklin County Building Permit FAQ
- Do I need a building permit in unincorporated Franklin County, ID?
- Building permits are required for residential and commercial construction in unincorporated Franklin County.
- How do I apply for a building permit in unincorporated Franklin County, ID?
- 1. Obtain septic permit from Southeast Idaho Public Health District before proceeding. 2. Submit completed building permit application with required documentation to Franklin County Building Inspector. 3. County reviews application for completeness and compliance with Idaho Building Code (2018 IBC) and Idaho Residential Code (2018 IRC). 4. Pay required permit fees upon approval. 5. Receive permit issuance and commence construction.
- How long does it take to get a building permit in unincorporated Franklin County, ID?
- Typical processing time is Minimum 30 days from complete application submission.
- How do I schedule a building inspection in unincorporated Franklin County, ID?
- Inspections can be scheduled via: (208) 220-2120.
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