What work is exempt from building permits in unincorporated Crook County, WY?

The following work is generally exempt: No building code / no permit required for residential construction in unincorporated areas; One-Split Subdivision: Properties may be split once without going through the full subdivision review process, subject to the county's one-split regulation; Subdivision Exemptions: Crook County maintains subdivision exemption criteria. Contact the Planning Department for the current exemption list.; Agricultural exemptions: Agricultural land uses and accessory farm structures are generally outside the scope of any local code in Crook County given the absence of a building code. Note: The absence of a county building permit program is confirmed by multiple independent sources. However, county policies can change; always verify current requirements with the Planning Department at (307) 283-4548 before breaking ground.

How do I schedule a building inspection in unincorporated Crook County, WY?

Inspections can be scheduled via: . Prior to backfilling or covering the septic system.

County Building Permits

Crook County, WY - 2026 Building Permit Guide

How to apply for a building permit in unincorporated Crook County, Wyoming. Permit authority, application steps, fees, and inspection requirements.

Wyoming Updated March 2026

Permit Authority

Covers all unincorporated areas of Crook County. Does not cover the incorporated municipalities of Sundance, Hulett, Moorcroft, or Pine Haven.

Department: Crook County Growth and Development Department
Address: Crook County Courthouse, 309 Cleveland Street, Sundance, WY 82729 (mailing: PO Box 825, Sundance, WY 82729)
Phone: (307) 283-4548
Email: timl@crookcounty.wy.gov
Website: https://www.crookcounty.wy.gov/departments/growth_and_development/index.php

Online Permit Portal

Open Crook County Growth and Development

Platform: • Account required: No • Submission: In-person only

Additional resources:

Application Process

Download the Crook County Conventional Small Wastewater Application Packet from the county website or obtain from the Growth and Development Department
Complete the application and include all required documentation (site plan, soil evaluation, system design by a licensed Wyoming engineer or sanitarian where applicable)
Submit completed application to the Growth and Development Department with the $200.00 permit fee
Crook County Planning Administrator reviews for compliance with the Crook County Small Wastewater Regulation
Permit to Construct issued
Construct the system
Contact Caleb Peters to schedule the required inspection prior to backfilling or covering the system
Inspection passed; system may be covered

Source: Crook County Growth and Development Department

General Requirements

Crook County has NOT adopted a county-wide building code for private residential construction. No general building permit for residential construction in unincorporated areas is apparent from publicly available sources. Septic permit required whenever a new on-site wastewater system is installed.

Required Documents

Site plan
Soil evaluation
System design by a licensed Wyoming engineer or sanitarian (where applicable)

Building code: None formally adopted for private residential construction in unincorporated areas. The county recommends following the Wyoming Building Code (2021 IBC base) and related I-Codes voluntarily for structural and life-safety purposes.
Owner-builder: No county restriction identified; owner-builder construction is permissible in the unincorporated county.
Contractor requirements: No county-level contractor license requirement. Wyoming does not have a statewide general contractor license. Electrical work requires a licensed electrician under Wyoming State Fire Marshal rules.

Fees

Payment note: In person at the Growth and Development Department; check or cash assumed -- confirm with office

Work That Does NOT Require a Permit

No building code / no permit required for residential construction in unincorporated areas
One-Split Subdivision: Properties may be split once without going through the full subdivision review process, subject to the county's one-split regulation
Subdivision Exemptions: Crook County maintains subdivision exemption criteria. Contact the Planning Department for the current exemption list.
Agricultural exemptions: Agricultural land uses and accessory farm structures are generally outside the scope of any local code in Crook County given the absence of a building code

Important: The absence of a county building permit program is confirmed by multiple independent sources. However, county policies can change; always verify current requirements with the Planning Department at (307) 283-4548 before breaking ground.

Inspections

How to Schedule

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Scheduling deadline: Prior to backfilling or covering the septic system

Typical inspection sequence: Septic inspection required prior to backfilling or covering the system. Electrical inspections performed by the Wyoming State Fire Marshal's Office/Electrical Safety Division for work requiring a state electrical wiring permit.

Additional Resources

Building code: None formally adopted for private residential construction in unincorporated areas. The county recommends following the Wyoming Building Code (2021 IBC base) and related I-Codes voluntarily for structural and life-safety purposes.
Zoning information: View zoning info
License lookup guide: Wyoming Contractor License Requirements
Contract template: Wyoming Homeowner-Contractor Agreement
Wyoming hub: Wyoming Contractor License & Permit Hub

Information on this page was last verified: March 2026. Permit rules and fees change — confirm current requirements directly with the Crook County Growth and Development Department before applying.

Frequently Asked Questions

Crook County Building Permit FAQ

Do I need a building permit in unincorporated Crook County, WY?: Crook County has NOT adopted a county-wide building code for private residential construction. No general building permit for residential construction in unincorporated areas is apparent from publicly available sources. Septic permit required whenever a new on-site wastewater system is installed.
How do I apply for a building permit in unincorporated Crook County, WY?: 1. Download the Crook County Conventional Small Wastewater Application Packet from the county website or obtain from the Growth and Development Department 2. Complete the application and include all required documentation (site plan, soil evaluation, system design by a licensed Wyoming engineer or sanitarian where applicable) 3. Submit completed application to the Growth and Development Department with the $200.00 permit fee 4. Crook County Planning Administrator reviews for compliance with the Crook County Small Wastewater Regulation 5. Permit to Construct issued 6. Construct the system 7. Contact Caleb Peters to schedule the required inspection prior to backfilling or covering the system 8. Inspection passed; system may be covered
What work is exempt from building permits in unincorporated Crook County, WY?: The following work is generally exempt: No building code / no permit required for residential construction in unincorporated areas; One-Split Subdivision: Properties may be split once without going through the full subdivision review process, subject to the county's one-split regulation; Subdivision Exemptions: Crook County maintains subdivision exemption criteria. Contact the Planning Department for the current exemption list.; Agricultural exemptions: Agricultural land uses and accessory farm structures are generally outside the scope of any local code in Crook County given the absence of a building code. Note: The absence of a county building permit program is confirmed by multiple independent sources. However, county policies can change; always verify current requirements with the Planning Department at (307) 283-4548 before breaking ground.
How do I schedule a building inspection in unincorporated Crook County, WY?: Inspections can be scheduled via: . Prior to backfilling or covering the septic system.

Need help with your project?

Navigating permits in Crook County (Unincorporated) can be complicated.

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Important: This page is an educational resource provided by jaspector.com. It is not legal advice, and it does not substitute for official guidance from the permit authority listed above. Permit requirements, fees, and processes change frequently. Always verify current requirements directly with the issuing department before beginning any construction project. Use of this page does not create an attorney-client relationship. Jaspector assumes no liability for any outcomes arising from reliance on this information.

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