Idaho building code

Codes in force in Idaho

Each code family with the edition and the date it took effect, as the adopting agency or statute states them.

Scope, amendments and transition rules

International Building Code (IBC): 2018 International Building Code, with amendments

Scope

Statewide minimum; local governments may go further⁸

Local amendments allowed?

Yes⁸

Amendments

IDAPA 24.39.30.600.01²

Next edition (not yet in force)

These boards are not currently engaged in rulemaking for 2026–2027. Existing rules remain in effect and are available above.⁹

International Building Code (IBC): International Building Code, 2021 Edition (mass timber provisions)

Scope

Statewide minimum; local governments may go further⁸

Local amendments allowed?

Yes⁸

Amendments

IDAPA 24.39.30.600.02²

International Residential Code (IRC)

Scope

Statewide minimum; local governments may go further⁸

Local amendments allowed?

Yes⁸

Amendments

IDAPA 24.39.30.600.03²

Next edition (not yet in force)

These boards are not currently engaged in rulemaking for 2026–2027. Existing rules remain in effect and are available above.⁹

International Existing Building Code (IEBC)

Next edition (not yet in force)

These boards are not currently engaged in rulemaking for 2026–2027. Existing rules remain in effect and are available above.⁹

Energy code, residential

Scope

Statewide minimum; local governments may go further⁸

Amendments

IDAPA 24.39.30.600.06²

Next edition (not yet in force)

These boards are not currently engaged in rulemaking for 2026–2027. Existing rules remain in effect and are available above.⁹

Energy code, commercial

Scope

Statewide minimum; local governments may go further⁸

Amendments

IDAPA 24.39.30.600.05²

Next edition (not yet in force)

These boards are not currently engaged in rulemaking for 2026–2027. Existing rules remain in effect and are available above.⁹

National Electrical Code (NEC)

Scope

Statewide; applies everywhere³

Applies to

Local-jurisdiction electrical permit programs exist in several cities and counties¹⁰

Uniform Plumbing Code (UPC)

Scope

Statewide; applies everywhere⁴

International Mechanical Code (IMC)

Scope

Statewide; applies everywhere⁵

International Fuel Gas Code (IFGC)

Scope

Statewide; applies everywhere⁵

International Fire Code (IFC)

Scope

Statewide; applies everywhere⁷

How Idaho adopts building codes

Idaho Code § 39-4116; IDAPA 24.39.30.600

• Local governments that issue building permits and perform building code enforcement; a local government with no program may elect one. Local governments that have not previously instituted and implemented a code enforcement program prior to the effective date of this act may elect to implement a building code enforcement program by passing an ordinance evidencing the intent to do so.⁸
• Statewide minimum; local governments may go further. Local governments that issue building permits and perform building code enforcement activities shall, by ordinance effective January 1 of the year following the adoption by the Idaho building code board, adopt the following codes as published by the International Code Council together with any amendments or revisions set forth in section 39-4109, Idaho Code, including subsequent versions of the International Building Code as adopted and amended by the Idaho building code board through the negotiated rulemaking process provided in this chapter…⁸
• (4) Except as provided in this subsection, local governments may amend by ordinance the adopted codes or provisions of referenced codes to reflect local concerns, provided such amendments establish at least an equivalent level of protection to that of the adopted building code.⁸
• (c) Local jurisdictions may amend by ordinance the following provisions of the Idaho residential code to reflect local concerns: (i) Part I, Administrative; (ii) Part II, Definitions; (iii) Part III, Building Planning and Construction, Section R 301, Design Criteria; and (iv) Part IX, Appendices.⁸
• Local jurisdictions shall not adopt provisions, chapters, sections or parts of subsequent versions of the International Residential Code or residential provisions of the International Energy Conservation Code, or subsequent versions in their entirety, that have not been adopted by the Idaho building code board except as provided in subsection (4) of this section.⁸
• (3) All single family homes and multiple family dwellings up to two (2) units are hereby exempted from the provisions of the International Fire Code, the International Building Code and the Idaho residential code that require such dwellings to have automatic fire sprinkler systems installed.⁸
• Law at application. (6) Permits shall be governed by the laws in effect at the time the permit application is received.⁸
• Idaho Building Code Board. Pursuant to Sections 39-4109 and 39-4109A, Idaho Code, the Board adopts the following international codes with identified amendments: (7-1-24)…²
• None pending. These boards are not currently engaged in rulemaking for 2026–2027. Existing rules remain in effect and are available above.⁹

Applies to

Local governments that enforce building codes⁸

Can local rules be stricter?

Yes⁸

For permits, exemptions and owner-builder rules, see Idaho building permits. To compare editions across states, see the code adoption map.