| IBC — International Building Code | 2021 IBC — MODULAR UNITS ONLY. MISSOURI HAS NO GENERAL STATEWIDE BUILDING CODE; ordinary construction is governed only by whatever a city, county or fire protection district has adopted locally. | 20 CSR 4240-123.080(3) (modular units); authority RSMo 700.010 and 700.040 (2016). No general statewide building code: RSMo 67.280 leaves adoption to each county, municipality or fire protection district by ordinance. · source ↗ |
| IECC — International Energy Conservation Code | NONE — MISSOURI HAS NO STATEWIDE ENERGY CODE AND NO EDITION OF THE INTERNATIONAL ENERGY CONSERVATION CODE IS ADOPTED AT STATE LEVEL FOR ANY PRIVATE CONSTRUCTION. The only statewide energy-efficiency instrument is a STATE-BUILDINGS-ONLY rule, 10 CSR 140-7.010, and that rule does not name the IECC at all: it still incorporates ASHRAE 90.1 (1989), ASHRAE 90.2 (1993) and the CABO Model Energy Code (1993 plus 1994 Amendments) by "latest edition" language written before the IECC existed. Missouri's modular-unit rule 20 CSR 4240-123.080(3), which does carry 2021 editions of the IBC/IPC/IMC/IRC/IFGC and NFPA 70-2020, OMITS the IECC entirely. SCOPE OF THE STATE-BUILDINGS RULE: construction of a state building over 5,000 sq ft, substantial renovation of a state building over 5,000 sq ft when major energy systems are involved, and any building over 5,000 sq ft the state or a state agency acquires or leases, for design initiated on or after July 1, 2009 (RSMo 8.812.1-.2); leases of 10,000 sq ft or greater procured on or after Jan. 1, 1996 "should conform to the minimum energy efficiency standard"; the commissioner of the Office of Administration may exempt a building where compliance would compromise safety or where cost of compliance is expected to exceed projected energy cost savings (RSMo 8.812.3). Energy requirements for ordinary site-built residential and commercial construction exist only where a city or county has adopted a code by ordinance. | 10 CSR 140-7.010 (State Building Minimum Energy Efficiency Standards; authority "sections 8.800-8.851, RSMo (1994)"; original rule filed July 11, 1995, effective Feb. 25, 1996; moved to 4 CSR 340-7.010 effective Aug. 28, 2013; moved to 10 CSR 140-7.010 effective Jan. 15, 2020); enabling statute RSMo 8.812 (state buildings over 5,000 sq ft; standard "shall be at least as stringent as the International Energy Conservation Code 2006, or the latest version thereof"; effective Aug. 28, 2008); definitions RSMo 8.800 ("department" = the department of economic development). No general statewide energy code — adoption for private construction is left to each county, municipality or fire protection district by ordinance under RSMo 67.280. 20 CSR 4240-123.080(3) (modular units, eff. Nov. 30, 2024) adopts the 2021 IBC/IPC/IMC/IRC/IFGC and NFPA 70-2020 but NOT the IECC. · source ↗ |
| IFC — | NONE — MISSOURI HAS NO STATEWIDE FIRE CODE OF ANY KIND, AND NO EDITION OF THE INTERNATIONAL FIRE CODE IS ADOPTED AT STATE LEVEL. Fire codes exist in Missouri only where an individual city, town, village or county has adopted one by ordinance. There is no edition to record because there is no state adoption. | RSMo 321.228 (fire protection district construction codes advisory only and unenforceable where a city, town, village or county regulates residential construction); RSMo 320.202 (Division of Fire Safety — rulemaking limited to that section, NO code-adoption power); RSMo 320.310 (fire department boundaries, adopts no standard); 11 CSR 40 chs. 1-7 (Division of Fire Safety rules — boilers, fireworks, elevators, amusement rides, blasting; NO fire code chapter). Local adoption route: RSMo 67.280. · source ↗ |
| IMC — International Mechanical Code | 2021 IMC — FACTORY-BUILT MODULAR UNITS ONLY. MISSOURI HAS NO GENERAL STATEWIDE MECHANICAL CODE. The single statewide adoption of the International Mechanical Code in Missouri reaches modular units through the Public Service Commission modular-unit rule, 20 CSR 4240-123.080(3), effective 2024-11-30. For mechanical work in ordinary site-built construction there is NO state edition to name: it is governed only by whatever a city, county or fire protection district has adopted by ordinance under RSMo 67.280, and in much of Missouri by nothing at all. NOT 2024 — the commission-adopted vintage is 2021. | 20 CSR 4240-123.080(3) (Missouri Public Service Commission — Manufactured Homes and Modular Units; Construction Standards for Modular Units), authority sections 700.010 and 700.040, RSMo 2016; original rule filed 1979-08-16 eff. 1979-12-15, last amended 2024-04-24 eff. 2024-11-30. No general statewide mechanical code exists: adoption for ordinary construction is left to each county, municipality or fire protection district by ordinance under RSMo 67.280. · source ↗ |
| IPC — International Plumbing Code | 2021 IPC — MODULAR UNITS ONLY. MISSOURI HAS NO GENERAL STATEWIDE PLUMBING CODE. The only statewide adoption of the International Plumbing Code in Missouri reaches factory-built MODULAR UNITS, through the Public Service Commission modular-unit rule. For plumbing in ordinary site-built construction there is no state edition to name: it is governed only by whatever a city or county has adopted by ordinance, and — in first class counties that have opted in — by Missouri own statutory plumbing text. | 20 CSR 4240-123.080(3) (modular units), authority RSMo 700.010 and 700.040; Missouri statutory plumbing scheme RSMo 341.090 to 341.220 ("Uniform Plumbing Code", first class counties only, RSMo 341.100); no general statewide plumbing code — local adoption left to each county, municipality or fire protection district by ordinance under RSMo 67.280 · source ↗ |
| IRC — International Residential Code | NONE FOR ORDINARY SITE-BUILT HOUSING — MISSOURI HAS NO STATEWIDE RESIDENTIAL BUILDING CODE AND ADOPTS NO EDITION OF THE INTERNATIONAL RESIDENTIAL CODE FOR PRIVATE HOMES. A house in Missouri is governed only by whatever code the individual county, municipality or fire protection district has adopted by ordinance under RSMo 67.280 — and in much of the state, by none. THE ONE NARROW STATEWIDE POSITIVE: the 2021 IRC applies to FACTORY-BUILT MODULAR UNITS ONLY, via 20 CSR 4240-123.080(3) (Public Service Commission, eff. 2024-11-30), the same rule that carries the 2021 IBC/IPC/IMC/IFGC and NFPA 70-2020 on sibling rows d72d8d8e and 93314f70. NOT 2024, and NOT statewide for site-built construction. | RSMo 67.281 (statewide mandate on every local residential code: purchaser sprinkler option, and retention of 2006 IRC R317 language where R313 sprinklers are not mandated), effective 2016-08-28; RSMo 67.280 (the local adoption route — counties, municipalities and fire protection districts may incorporate codes by reference), effective 2009-08-28; 20 CSR 4240-123.080(3) (2021 IRC, MODULAR UNITS ONLY, eff. 2024-11-30, authority RSMo 700.010 and 700.040). NO GENERAL STATEWIDE RESIDENTIAL CODE ADOPTION EXISTS IN MISSOURI. · source ↗ |
| NEC — National Electrical Code (NFPA 70) | 2020 NEC (NFPA 70-2020) — FACTORY-BUILT MODULAR UNITS ONLY. MISSOURI HAS NO GENERAL STATEWIDE ELECTRICAL CODE AND ADOPTS NO NEC EDITION FOR ORDINARY SITE-BUILT CONSTRUCTION, PRIVATE OR PUBLIC. The single statewide adoption of the National Electrical Code in Missouri reaches modular units through the Public Service Commission modular-unit rule, 20 CSR 4240-123.080(3), effective 2024-11-30. Subsection (3) verbatim: "The structure shall be manufactured in accordance with and meet the requirements of the most recently commission-adopted building codes: except as provided in subsections (A) and (B) below, International Building Code-2021; International Plumbing Code-2021; International Mechanical Code-2021; International Residential Code-2021; International Fuel Gas Code-2021; and National Electric Code NFPA 70-2020." NOTE THE EDITION SPLIT INSIDE THE SENTENCE: five 2021 I-Codes and a 2020 NEC — the electrical edition is deliberately a year off its list-mates because there is no 2020 I-Code and no 2021 NEC. NOT 2023 NEC, NOT 2026 NEC. Transition rule, verbatim: "Manufacturers will have six (6) months in which to update to the new code after the effective date of this rule as notified by the manager for all units built on or after that date." FOR EVERY OTHER KIND OF ELECTRICAL WORK IN MISSOURI THERE IS NO STATE EDITION TO NAME: it is governed only by whatever a city, county or fire protection district has adopted by ordinance under RSMo 67.280, and in much of Missouri by nothing at all. ** AND THE SHARPEST MISSOURI FINDING IS AN EDITION-LESS ONE: MISSOURI RUNS A STATEWIDE ELECTRICAL CONTRACTOR LICENSING SCHEME THAT NAMES THE NEC WITHOUT EVER NAMING AN EDITION. 20 CSR 2117-1.010(8) defines the term, verbatim and in its entirety: "National Electrical Code (NEC)-The National Electrical Code." — the definition is the name of the code and nothing else. 20 CSR 2117-2.020 then requires an approved licensing examination to be, verbatim, "based upon the National Electrical Code, nationally standardized, and administered by an independent professional testing agency", again with NO edition year. SO MISSOURI LICENSES ELECTRICIANS STATEWIDE AGAINST A CODE IT DECLINES TO DATE, WHILE ADOPTING A DATED EDITION ONLY FOR MODULAR UNITS. ** A national table printing one edition year for "Missouri" electrical is printing a number that is not in Missouri law for any site-built project. | 20 CSR 4240-123.080(3) (Missouri Public Service Commission — Manufactured Homes and Modular Units; Code for Modular Units). AUTHORITY verbatim: "sections 700.010 and 700.040, RSMo 2016." Full history verbatim: "This rule originally filed as 4 CSR 240-123.080. Original rule filed Aug. 16, 1979, effective Dec. 15, 1979. Emergency amendment filed July 3, 1989, effective July 13, 1989, expired Nov. 9, 1989. Amended: Filed July 3, 1989, effective Nov. 1, 1989. Amended: Filed June 12, 2001, effective Jan. 30, 2002. Amended: Filed Oct. 15, 2007, effective April 30, 2008. Amended: Filed Oct. 4, 2010, effective April 30, 2011. Amended: Filed July 6, 2017, effective March 30, 2018. Moved to 20 CSR 4240-123.080, effective Aug. 28, 2019. Amended: Filed April 24, 2024, effective Nov. 30, 2024." No general statewide electrical code: adoption for ordinary construction is left to each county, municipality or fire protection district by ordinance under RSMo 67.280. Statewide electrical contractor licensing, NEC named but NO edition adopted: 20 CSR 2117-1.010(8) (definition) and 20 CSR 2117-2.020 (examination must be "based upon the National Electrical Code"). Statewide local-code mandate on residential sprinklers: RSMo 67.281. · source ↗ |