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§ 02
When a permit is required
Permit triggers and exempt work for Ada County
New construction, additions, structural alterations, demolition, relocations, and most improvements to structures in unincorporated Ada County.
One-story detached accessory structures (tool sheds, playhouses, similar) with floor area not exceeding 200 sq. ft.
Fences not over 6 feet high (subject to zoning setback requirements; no permit required but zoning standards still apply)
Decks not more than 30 inches above grade at any point that do not serve as an exit
Painting, flooring, cabinets, countertops, and wall coverings (interior cosmetic work)
Agricultural buildings meeting IBC definition of 'Ag Buildings' (must still comply with zoning setbacks)
Concrete slabs
- Exempt One-story detached accessory structures (tool sheds, playhouses, similar) with floor area not exceeding 200 sq. ft.
- Exempt Fences not over 6 feet high (subject to zoning setback requirements; no permit required but zoning standards still apply)
- Exempt Decks not more than 30 inches above grade at any point that do not serve as an exit
- Exempt Painting, flooring, cabinets, countertops, and wall coverings (interior cosmetic work)
- Exempt Agricultural buildings meeting IBC definition of 'Ag Buildings' (must still comply with zoning setbacks)
- Exempt Concrete slabs
Note: MEP (mechanical, electrical, plumbing) permits are handled separately; contact Idaho DBS for trade permit exemptions.
Required documents
- Completed building permit application
- Site plan showing property lines and structure locations
- Construction drawings
- Building code
- 2018 International Building Code (IBC), 2018 International Residential Code (IRC), 2018 International Energy Conservation Code (IECC), 2017 Idaho State Plumbing Code, 2018 International Mechanical Code, 2018 International Fuel Gas Code, 2018 International Urban-Wildland Interface Code, and the National Electrical Code (updated November 2025)
- Permit validity
- Work must commence or resume within 180 days; permit is invalid if work does not commence within that period. Extensions require contacting the department before expiration.
- Owner-builder
- Homeowners may pull permits on their primary residence if they perform the work themselves.
- Contractor requirements
- Licensed contractors must hold a current, valid State of Idaho contractor license.
§ 03
Application process
Typical processing: Not published; contact department for current turnaround times.
- 01 Determine that the project address is in unincorporated Ada County (not within any city limits).
- 02 Prepare required documents: completed building permit application, site plan, and construction drawings.
- 03 Submit application online through the COBRA portal or in person at the Ada County Courthouse, Second Floor.
- 04 The Permitting Team reviews the application for completeness and contacts you for payment.
- 05 Pay via e-check or credit card; your application officially enters the review queue after payment.
- 06 Building Division reviews plans for compliance with Ada County Building Code.
- 07 Permit is issued when plans are approved.
- 08 Post permit card on site and schedule inspections at required stages.
- 09 Complete all required inspections and final permit closeout.
Typical processing time: Not published; contact department for current turnaround times.
Source: Ada County Development Services — Building Division ↗
§ 04
Fee schedule
Effective November 2025
Fee type
Amount
01
Permit fee formula
Valuation-based; fees set per Ada County fee schedule (updated November 2025; contact department for details)
E-check accepted ($3.00 flat fee); credit card accepted (2.4% convenience fee, minimum $2.00). Payment required before application enters review.
Fees change periodically. Confirm at the official fee schedule ↗ (effective November 2025) before budgeting.
§ 05
Required inspections
Scheduling and sequence
How to schedule
- (208) 287-7900 (phone)
- COBRA portal inspection request page (online)
- Scheduling deadline
- Inspections must be requested the business day before, by 4:30 PM via phone or by midnight via the portal/email.
- Inspection hours
- Monday-Friday (weekend inspections not available)
Typical sequence: Typical sequence: footing/foundation, framing, rough mechanical/electrical/plumbing (as applicable), insulation, final inspection.
§ 06
Frequently asked
Common questions about unincorporated Ada County permits
01 Do I need a building permit in unincorporated Ada County, ID? ▸
New construction, additions, structural alterations, demolition, relocations, and most improvements to structures in unincorporated Ada County.
02 How much does a building permit cost in unincorporated Ada County, ID? ▸
Building permit fees in unincorporated Ada County, ID are set by the local building department and vary by project type and valuation. Fees are calculated as: Valuation-based; fees set per Ada County fee schedule (updated November 2025; contact department for details).
03 How do I apply for a building permit in unincorporated Ada County, ID? ▸
To apply for a building permit in unincorporated Ada County, ID, follow these steps: 1. Determine that the project address is in unincorporated Ada County (not within any city limits). 2. Prepare required documents: completed building permit application, site plan, and construction drawings. 3. Submit application online through the COBRA portal or in person at the Ada County Courthouse, Second Floor. 4. The Permitting Team reviews the application for completeness and contacts you for payment. 5. Pay via e-check or credit card; your application officially enters the review queue after payment. 6. Building Division reviews plans for compliance with Ada County Building Code. 7. Permit is issued when plans are approved. 8. Post permit card on site and schedule inspections at required stages. 9. Complete all required inspections and final permit closeout.
04 How long does it take to get a building permit in unincorporated Ada County, ID? ▸
Building permit processing times in unincorporated Ada County, ID typically run Not published; contact department for current turnaround times.. Timelines can vary based on project complexity and current department workload.
05 What work is exempt from building permits in unincorporated Ada County, ID? ▸
Not all construction work requires a permit in unincorporated Ada County, ID. The following work is generally exempt: One-story detached accessory structures (tool sheds, playhouses, similar) with floor area not exceeding 200 sq. ft.; Fences not over 6 feet high (subject to zoning setback requirements; no permit required but zoning standards still apply); Decks not more than 30 inches above grade at any point that do not serve as an exit; Painting, flooring, cabinets, countertops, and wall coverings (interior cosmetic work); Agricultural buildings meeting IBC definition of 'Ag Buildings' (must still comply with zoning setbacks); Concrete slabs. Note: MEP (mechanical, electrical, plumbing) permits are handled separately; contact Idaho DBS for trade permit exemptions. When in doubt, confirm with the local building department before starting work.
06 How do I schedule a building inspection in unincorporated Ada County, ID? ▸
Once your permit is issued and work reaches an inspection milestone, you can schedule a building inspection in unincorporated Ada County, ID via: (208) 287-7900, COBRA portal inspection request page. Inspections must be requested the business day before, by 4:30 PM via phone or by midnight via the portal/email..
last verified April 2026
source Ada County Development Services — Building Division ↗
entry id permits/idaho/ada/unincorporated
Educational reference. Permit rules and fees change — confirm current requirements directly with Ada County Development Services — Building Division before applying. Jaspector is not legal advice.