Custer County, ID - 2026 Building Permit Guide

Permit Authority

All unincorporated areas of Custer County, Idaho.

Department

Custer County Planning & Zoning Department

Address

PO Box 385, Challis, ID 83226

Phone

208-879-2379

Website

https://custercountyidaho.org

Application Process

1. Contact Custer County Planning & Zoning Department by phone or mail.
2. Obtain zoning compliance certificate and site evaluation form (if septic required).
3. Obtain approved septic permit from Eastern Idaho Public Health (if applicable).
4. Submit building notification application with all required documents and approved septic permit attached.
5. County reviews for zoning compliance and floodplain status.
6. County issues building notification.
7. Obtain separate electrical, plumbing, and HVAC permits from Idaho Division of Building Safety if required.

Typical processing time: Zoning certificate: 1-3 business days. Septic permit: 5-10 business days. Building notification: 2-5 business days after septic approval.

General Requirements

Building notification required for residential construction (new homes, additions, major renovations), commercial/industrial buildings, subdivisions, and most structures. An approved septic permit must be attached to the building notification per Ordinance 2007-13.

Required Documents

• Building notification application form
• Site plan or sketch showing proposed structure, setbacks, lot lines
• Proof of property ownership
• Approved septic permit (if applicable)
• Flood information and elevation certificate (if in mapped floodplain)
• Zoning compliance certification

Building code

2018 International Building Code (IBC), 2018 International Residential Code (IRC) with Idaho state amendments.

Owner-builder

Owner-builders may install basic septic systems on their own property without hired labor; otherwise, licensed septic installer required.

Contractor requirements

Contractor registration required for projects totaling $2,000 or more (labor, materials, and all other items). Registration number must be presented before permit issuance.

Fees

Payment note

Zoning compliance certificate: $25-$50. Building notification: $0-$75 depending on project value. Septic permit: $100-$300 (Eastern Idaho Public Health); site evaluation adds $75-$150.

Work That Does NOT Require a Permit

Contact the Custer County Planning & Zoning Department to confirm whether your project requires a permit before starting work.

Inspections

How to Schedule

Inspection hours

Weekdays during business hours

Additional Resources

• Building code: 2018 International Building Code (IBC), 2018 International Residential Code (IRC) with Idaho state amendments.
• Verify contractor license: Idaho DOPL License Lookup
• Eastern Idaho Public Health (Septic Permits)
• Idaho Division of Building Safety (IDBS)
• Idaho DEQ Stormwater Permits
• License lookup guide: Idaho Contractor License Requirements
• Contract template: Idaho Homeowner-Contractor Agreement
• Idaho hub: Idaho Contractor License & Permit Hub

Frequently Asked Questions

Custer County Building Permit FAQ

Do I need a building permit in unincorporated Custer County, ID?

Building notification required for residential construction (new homes, additions, major renovations), commercial/industrial buildings, subdivisions, and most structures. An approved septic permit must be attached to the building notification per Ordinance 2007-13.

How do I apply for a building permit in unincorporated Custer County, ID?

1. Contact Custer County Planning & Zoning Department by phone or mail. 2. Obtain zoning compliance certificate and site evaluation form (if septic required). 3. Obtain approved septic permit from Eastern Idaho Public Health (if applicable). 4. Submit building notification application with all required documents and approved septic permit attached. 5. County reviews for zoning compliance and floodplain status. 6. County issues building notification. 7. Obtain separate electrical, plumbing, and HVAC permits from Idaho Division of Building Safety if required.

How long does it take to get a building permit in unincorporated Custer County, ID?

Typical processing time is Zoning certificate: 1-3 business days. Septic permit: 5-10 business days. Building notification: 2-5 business days after septic approval..

What work is exempt from building permits in unincorporated Custer County, ID?

The following work is generally exempt: Minor farm buildings; Minor storage sheds under specified square footage (consult county for exact thresholds); Certain exempt structures per local ordinance. Note: Consult Custer County Planning & Zoning Department for specific exemption determinations. Building notification exemption does not mean exemption from zoning and planning requirements.