Amends existing law to require certain heat detection devices in certain attached garages and to provide an exemption from a requirement of fire sprinklers for certain multiple-family dwellings with fire walls.

LEGISLATURE OF THE STATE OF IDAHO Sixty-eighth Legislature Second Regular Session - 2026 IN THE HOUSE OF REPRESENTATIVES HOUSE BILL NO. 643 BY BUSINESS COMMITTEE AN ACT1 RELATING TO BUILDING CODES; AMENDING SECTION 39-4116, IDAHO CODE, TO PROVIDE2 FOR CERTAIN HEAT DETECTION DEVICES, TO CLARIFY A TERM, AND TO MAKE TECH-3 NICAL CORRECTIONS; AND DECLARING AN EMERGENCY AND PROVIDING AN EFFEC-4 TIVE DATE.5

Be It Enacted by the Legislature of the State of Idaho:6

SECTION 1. That Section 39-4116, Idaho Code, be, and the same is hereby7 amended to read as follows:8 39-4116. LOCAL GOVERNMENT ADOPTION AND ENFORCEMENT OF BUILDING9 CODES. (1) Local governments enforcing building codes shall do so only in10 compliance with the provisions of this section. Local governments that have11 not previously instituted and implemented a code enforcement program prior12 to the effective date of this act may elect to implement a building code13 enforcement program by passing an ordinance evidencing the intent to do so.14 Local governments may contract with a public or private entity to administer15 their building code enforcement program.16 (2) Local governments that issue building permits and perform build-17 ing code enforcement activities shall, by ordinance effective January 1 of18 the year following the adoption by the Idaho building code board, adopt the19 following codes as published by the International Code Council together with20 any amendments or revisions set forth in section 39-4109, Idaho Code, in-21 cluding subsequent versions of the International Building Code as adopted22 and amended by the Idaho building code board through the negotiated rulemak-23 ing process provided in this chapter:24 (a) International Building Code, including all rules promulgated by25 the board to provide equivalency with the provisions of the Americans26 with disabilities act accessibility guidelines and the federal fair27 housing act accessibility guidelines;28 (b) Idaho residential code, parts I-III and IX; and29 (c) 2018 Idaho energy conservation code, pursuant to chapter 97, title30 39, Idaho Code.31 Local governments are not required by this chapter to adopt the other refer-32 enced codes in the International Building Code. Local jurisdictions shall33 not adopt provisions, chapters, sections or parts of subsequent versions34 of the International Residential Code or residential provisions of the35 International Energy Conservation Code, or subsequent versions in their36 entirety, that have not been adopted by the Idaho building code board except37 as provided in subsection (4) of this section.38 (3)(a) All single-family homes and multiple-family dwellings up to two39 (2) units are hereby exempted from the provisions of the International40 Fire Code, the International Building Code and the Idaho residential41 code that require such dwellings to have automatic fire sprinkler sys-42

2 tems installed. However, for this exemption to apply to any single-fam-1 ily home or multiple-family dwelling up to two (2) units for which a2 building permit is issued for new construction on or after July 1, 2026,3 such unit shall have a heat detection device with a suitable temperature4 rating installed in any attached garage. Any such heat detection de-5 vice shall be interconnected with the smoke alarm system for the home or6 dwelling unit to which the garage is attached. Nothing in this section7 shall prevent any person from voluntarily installing an automatic fire8 sprinkler system in any residential dwelling.9 (b) For the purpose of this subsection, the term "multiple-family10 dwelling up to two (2) units" includes multiple-family dwellings that11 exceed two (2) units if:12 (i) The building permit for new construction was issued on or af-13 ter July 1, 2026;14 (ii) No more than two (2) units are on the same side of the same two15 (2) hour fire wall between dwelling units; and16 (iii) The fire wall separating dwelling units is constructed from17 the lowest portion of the unit and extends to the roof of the unit18 without any penetrations.19 (4) Except as provided in this subsection, local governments may amend20 by ordinance the adopted codes or provisions of referenced codes to reflect21 local concerns, provided such amendments establish at least an equivalent22 level of protection to that of the adopted building code. A local jurisdic-23 tion shall not have the authority to amend any accessibility provision pur-24 suant to section 39-4109, Idaho Code, except as provided in this subsection.25 (a) A local jurisdiction shall not have the authority to amend any ac-26 cessibility provision pursuant to section 39-4109, Idaho Code.27 (b) A local jurisdiction shall not adopt any provision, chapter, sec-28 tion or part of the International Residential Code or residential pro-29 visions of the International Energy Conservation Code, or subsequent30 versions in their entirety, that have not been adopted or that have been31 expressly rejected or exempted from the adopted version of those codes32 by the Idaho building code board through the negotiated rulemaking33 process as provided in section 39-4109, Idaho Code.34 (c) Local jurisdictions may amend by ordinance the following provi-35 sions of the Idaho residential code to reflect local concerns:36 (i) Part I, Administrative;37 (ii) Part II, Definitions;38 (iii) Part III, Building Planning and Construction, Section R 301,39 Design Criteria; and40 (iv) Part IX, Appendices.41 (d) Local jurisdictions may amend the remainder of Part III of the42 Idaho residential code if they find that good cause for building or life43 safety exists for such an amendment to such codes and that such amend-44 ment is reasonably necessary. Amendments shall be adopted by ordinance45 in accordance with the provisions of chapter 9, title 50, Idaho Code, or46 chapter 7, title 31, Idaho Code, and provided further that such local47 jurisdiction shall conduct a public hearing and, provided further, that48 notice of the time and place of the public hearing shall be published49 in the official newspaper or paper of general circulation within the50

3 jurisdiction and written notice of each of such public hearing and the1 proposed language shall be given by the local jurisdiction to the lo-2 cal chapters of the entities identified in section 39-4109(5), Idaho3 Code, not less than thirty (30) days prior to such hearing. In the event4 that there are no local chapters of such entities identified in sec-5 tion 39-4109(5), Idaho Code, within the local jurisdiction holding the6 hearings, the notice shall be provided to the state associations of the7 respective entities.8 (5) Local governments shall exempt agricultural buildings from the re-9 quirements of the codes enumerated in this chapter and the rules promulgated10 by the board. A county may issue permits for agricultural buildings to as-11 sure compliance with road setbacks and utility easements, provided that the12 cost for such permits shall not exceed the actual cost to the county of issu-13 ing the permits.14 (a) For the purposes of this subsection, "agricultural buildings"15 means:16 (i) Livestock shelters or buildings, including shade structures17 and milking barns;18 (ii) Poultry buildings or shelters;19 (iii) Barns;20 (iv) Storage and maintenance structures for equipment and machin-21 ery used exclusively in agricultural operations;22 (v) Horticultural structures, including detached production23 greenhouses and crop protection shelters;24 (vi) Sheds used as part of an agricultural operation;25 (vii) Grain silos;26 (viii) Stables; and27 (ix) Any other structure designed, constructed, and intended to28 house, accommodate, or store farm implements, hay, grain, poul-29 try, livestock, or other horticultural products.30 (b) For the purposes of this subsection, "agricultural buildings" does31 not include:32 (i) A place of human habitation, which means a space in a build-33 ing for living, sleeping, or cooking. Structures with bathrooms,34 shower rooms, break rooms, locker rooms, storage or utility space,35 or other similar areas are not considered places of human habita-36 tion;37 (ii) A place of employment where agricultural products are pro-38 cessed, treated, or packaged; or39 (iii) A place used by the public.40 (c) Counties shall not alter, amend, deny, limit, or narrow the exemp-41 tion provided pursuant to this subsection by, including but not limited42 to, requiring size limitations of agricultural buildings, requiring43 maximum travel distances to exits within agricultural buildings, or44 requiring installation of automatic sprinkler systems in agricultural45 buildings.46 (6) Permits shall be governed by the laws in effect at the time the per-47 mit application is received.48 (7) The division shall retain jurisdiction for in-plant inspections49 and installation standards for manufactured or mobile homes and for in-plant50

4 inspections and enforcement of construction standards for modular buildings1 and commercial coaches.2

SECTION 2. An emergency existing therefor, which emergency is hereby3 declared to exist, this act shall be in full force and effect on and after4 July 1, 2026.5