Kuna ADU Guide
Summary of Kuna Ordinance 2026-05A (Apr 7, 2026) · ADU 900 sqft / 50% primary cap; owner-occupancy removed; parking waived within 1,500 ft of transit as it applies in Kuna. Reference: https://library.municode.com/id/kuna.
Code evolves continuously. Verify at the official source (https://library.municode.com/id/kuna) before any development decision.
Process
Step by step. Agency, timeline, fee, reference.
Typical sequence for this pathway. Timelines are ranges; each parcel varies.
- 01
Zoning Verification
Confirm parcel zoning via Ada County Assessor or Kuna Planning & Zoning. Verify R-2 Low Density Residential designation.
- 02
Building Permit Application
Submit building permit application with ADU site plan, floor plan, and utility connection plan to Kuna Building Department.
Agency: Kuna Building DepartmentReference → - 03
Utility Connection Approval
Obtain sewer, water, and storm drainage connection approvals from Kuna Public Works.
Agency: Kuna Public WorksReference → - 04
Construction & Inspection
Complete ADU construction per approved plans. Schedule inspections (foundation, framing, mechanical, electrical, plumbing, final) with Kuna Building Department.
Agency: Kuna Building DepartmentReference → - 05
Certificate of Occupancy
Obtain certificate of occupancy from Kuna Building Department after final inspection approval.
Renew analysis
Where this pathway usually breaks. And where it actually works.
R-2 zoning covers significant portions of Old Town Kuna and North Kuna neighborhoods. Verify parcel zoning via Ada County Assessor before acquisition — not all single-family parcels are R-2. R-1 and agricultural zones may prohibit ADUs entirely.
Without confirmed size caps, underwrite conservatively at 800–900 sq ft maximum until code verification. Neighboring Boise allows up to 900 sq ft or 70% of primary under ZOA25-000013; Kuna standards may differ.
Alley-facing lots in Old Town Kuna may offer setback advantages similar to Boise's 3-foot alley setback allowance. Confirm with Kuna Planning & Zoning before site planning.
Kuna lacks the frequent transit network of Boise, so parking waivers are unlikely. Budget for 1 off-street space per ADU unless code verification shows otherwise.
If Kuna's pre-2026 code required owner-occupancy, Idaho SB 1354 (effective July 1, 2026) overrides that requirement statewide. Out-of-state investors can hold ADU properties as rentals without owner-occupancy after July 1, 2026.
SB 1354 removes the owner-occupancy barrier for ADU investors statewide. Kuna must comply by July 1, 2026. Underwrite ADU rental income as a standalone asset class without requiring on-site landlord presence.