| IBC — International Building Code | 2021 IBC, chapters 2-35 and appendix H (ROLLING: adopts all SUBSEQUENTLY PUBLISHED errata and printings) | OAC 4101:1-1-01 sec. 101.1 (2024 Ohio Building Code, "Administration"), Ohio Board of Building Standards. OPERATIVE SENTENCE, QUOTED VERBATIM FROM THE FILED RULE TEXT: "the International Building Code 2021 edition, Chapters 2 through 35 and appendix H, as published by the 'International Code Council, Inc.' including all subsequently published errata and printings, and readily available at https://www.iccsafe.org, are hereby incorporated by reference in accordance with sections 121.71 to 121.74 of the Revised Code". AUTHORITY AS PRINTED ON THE RULE RECORD: ORC 3781.10(A)(1) and 4104.43(A)(1), promulgated under ORC 119.03. CURRENT RULE TEXT EFF. 2025-10-15; PRIOR EFFECTIVE DATES RUN FROM 1969-07-07 THROUGH 2024-03-01, AND 2024-03-01 IS THE EDITION FAMILY'S OWN DATE (the 2024 Ohio Building Code), WHICH IS WHAT effective_date CARRIES. *** DO NOT RECORD 2024 IBC. OHIO'S "2024 Ohio Building Code" IS BUILT ON THE **2021** IBC - THE STATE EDITION YEAR AND THE MODEL EDITION YEAR ARE DIFFERENT NUMBERS AND THIS IS THE SINGLE EASIEST ERROR TO MAKE IN THIS STATE. · source ↗ |
| IEBC — International Existing Building Code | 2021 IEBC, Chapters 2 to 16, Appendix A and Resource A (ROLLING: adopts all SUBSEQUENTLY PUBLISHED errata and printings). Model Chapter 1 is NOT incorporated -- Ohio writes its own. Served to readers as the "Ohio Existing Building Code (OEBC)". NOT the 2024 IEBC. | OAC 4101:1-34-01 ("Existing buildings"), chapter 4101:1-34 "Existing Structures" of the Ohio Administrative Code, Ohio Board of Building Standards. Incorporation by reference under ORC 121.71 to 121.74. Promulgated under ORC 119.03; statutory authority ORC 3781.10(A)(1); amplifies ORC 3781.10, 3781.11, 3791.04. Current rule text effective 2025-10-15; five-year review 2029-03-01. Prior effective dates: 1/1/2002, 1/1/2003, 3/1/2005, 9/6/2005, 7/1/2007, 11/1/2007, 11/1/2011, 3/15/2012, 11/1/2017, 8/1/2018, 3/1/2024 -- the 3/1/2024 entry is when the 2021 IEBC base took effect in Ohio with the 2024 Ohio Building Code family, and that is the date carried in effective_date; 2025-10-15 is the date of the current rule TEXT, not of the edition. · source ↗ |
| IECC — International Energy Conservation Code | TWO IECC EDITIONS ARE IN FORCE IN OHIO AT THE SAME TIME, SPLIT BY BUILDING TYPE, AND A SINGLE-EDITION ANSWER IS WRONG FOR HALF THE STATE. COMMERCIAL (2024 Ohio Building Code, OAC 4101:1): the 2021 IECC — Ch.35 Referenced Standards, OAC 4101:1-35-01, lists verbatim "IECC - 21 International Energy Conservation Code (adoption includes Chapters 2..."; OAC 4101:1-13-01 (Energy efficiency) directs that "Buildings are to be designed and constructed in accordance with the applicable provisions of the 'International Energy Conservation Code' or the requirements of 'ASHRAE 90.1' listed in Chapter 35", so ASHRAE 90.1-2019 ("90.1-19 Energy Standard for Buildings Except Lowrise Residential Buildings") is a CO-EQUAL COMPLIANCE PATH, not a fallback. RESIDENTIAL (Residential Code of Ohio, OAC 4101:8 — one-, two- and three-family dwellings): the 2018 IECC, listed in Ch.44 Referenced Standards, OAC 4101:8-44-01 (eff. 2024-04-15) verbatim as "IECC—18: International Energy Conservation Code(R)", THREE YEARS BEHIND THE COMMERCIAL CODE; and a SECOND, MUCH OLDER edition is simultaneously live for one section only — "IECC—06: International Energy Conservation Code(R) for use with 1101.6 only" (2006 IECC). NOT the 2024 IECC in any Ohio context. | OAC 4101:1-13-01 (Energy efficiency, 2024 Ohio Building Code Ch.13) read with OAC 4101:1-35-01 (Referenced standards: "IECC - 21"), both eff. 10/15/2025, edition family eff. 3/1/2024; residential via OAC 4101:8-11-01 (Residential Code of Ohio Ch.11, eff. 7/1/2019) read with OAC 4101:8-44-01 (Referenced standards: "IECC—18", and "IECC—06 ... for use with 1101.6 only"), eff. 4/15/2024. Adopter: Ohio Board of Building Standards. Authority ORC 3781.10(A)(1); amplifies ORC 3781.10, 3781.11, 3791.04 · source ↗ |
| IFC — | A SPLIT-EDITION ADOPTION — OHIO IS ON TWO IFC EDITIONS AT ONCE, DIVIDED BY CHAPTER, AND NO SINGLE EDITION YEAR IS A CORRECT ANSWER. The 2021 IFC for Chapters 1-11 and 20-80, AND THE 2024 IFC FOR CHAPTER 12 ALONE. Verbatim from OAC 1301:7-7-01: "Except as otherwise specified in Ohio Administrative Code Chapters 1301:7-7-01 through 1301:7-7-80, Chapters 1 through 11 and 20 through 80 of the 2021 edition of the International Fire Code and Chapter 12 of the 2024 edition of the International Fire Code, as published by the International Code Council, Inc., and readily available at https://www.iccsafe.org, are hereby incorporated by reference in accordance with Sections 121.71 to 121.74 of the Revised Code as if set out at length herein." IFC Chapter 12 is Energy Systems — the battery/energy-storage-system chapter, the fastest-moving chapter in the model fire code — so Ohio deliberately pulled that one chapter THREE YEARS FORWARD of the rest of its fire code. NOT a whole-code 2024 adoption, and NOT a clean 2021 adoption. | OAC 1301:7-7-01 (Ohio Fire Code, Scope and administration), State Fire Marshal, eff. 11/20/2025; incorporation by reference under ORC 121.71 to 121.74; authority ORC 3721.032, 3731.02(A),(E), 3731.03(D), 3731.041(A)(4),(5),(C), 3737.17(D), 3737.22(A)(1), 3737.82, 3737.83(A)-(G), 3737.831, 3737.832(B), 3737.842(A), 3737.85, 3737.86(B) · source ↗ |
| IMC — International Mechanical Code | A SPLIT-EDITION ADOPTION — OHIO IS ON TWO IMC EDITIONS AT ONCE, DIVIDED BY CHAPTER, AND NO SINGLE EDITION YEAR IS A CORRECT ANSWER. The 2021 IMC for Chapters 2 through 10 and Chapters 12 through 15, AND THE 2024 IMC FOR CHAPTER 11 ALONE. OAC 4101:2-1-01 sec. 101.1 (eff. 10/15/2025) incorporates by reference the "International Mechanical Code 2021 edition, Chapters 2 through 10 and Chapters 12 through 15" together with the "International Mechanical Code 2024 edition, Chapter 11", as published by the "International Code Council, Inc." IMC CHAPTER 11 IS REFRIGERATION (confirmed against the Ohio codification: OAC 4101:2-11 is titled "Refrigeration") — the chapter carrying refrigerant classification, machinery-room and A2L/flammable-refrigerant provisions, the fastest-moving chapter in the model mechanical code under the HFC phase-down. Ohio deliberately pulled that one chapter THREE YEARS FORWARD of the rest of its mechanical code. THIS IS THE SAME MANOEUVRE OHIO USED IN ITS FIRE CODE (OAC 1301:7-7-01: 2021 IFC except Chapter 12 Energy Systems from the 2024 IFC) — a deliberate, repeated Ohio pattern of forward-porting the single most volatile chapter while holding the rest of the book. NOT a whole-code 2024 adoption, and NOT a clean 2021 adoption. Model Chapter 1 is NOT incorporated: Ohio substitutes its own administrative chapter (OAC 4101:2-1), so the incorporation begins at Chapter 2 — the same partial-incorporation shape recorded for the Ohio Plumbing Code (Chapters 2 through 15). | OAC 4101:2-1-01 sec. 101.1 (Ohio Mechanical Code, Administration), Ohio Board of Building Standards, eff. 10/15/2025; incorporation by reference under ORC 121.71 to 121.74; authority ORC 3781.10(A)(1), amplifying ORC 3781.10, 3781.11, 3791.04; edition family (2024 Ohio Mechanical Code / 2021 IMC base) eff. 3/1/2024 · source ↗ |
| IPC — International Plumbing Code | 2021 | OAC 4101:3-1-01 sec. 101.1 (Ohio Plumbing Code, Administration), adopted by the Ohio Board of Building Standards; authority ORC 3781.10(A)(1) and 3781.11(A)(1), amplifying ORC 3781.10, 3781.11 and 3791.04; edition (2024 Ohio Plumbing Code / 2021 IPC base) eff. 3/1/2024, current rule text eff. 10/15/2025 · source ↗ |
| IRC — International Residential Code | 2018 IRC, FIRST PRINTING, chapters 2-24, 29 and 44 — BUT SEE amendments: OHIO DOES NOT INCORPORATE BY REFERENCE HERE, IT REPRINTS THE CODE AS STATE RULE TEXT | OAC 4101:8-1-01 sec. 101.1 (Residential Code of Ohio, "Administration"), Ohio Board of Building Standards. SCOPE SENTENCE, QUOTED VERBATIM FROM THE FILED RULE TEXT: "Chapters 4101:8-1 to 4101:8-25, 4101:8-29, 4101:8-34, and 4101:8-44 of the Administrative Code are designated as the 'Residential Code of Ohio for One-, Two-, and Three-Family Dwellings'". BASIS SENTENCE, QUOTED VERBATIM: "The 2018 edition of the 'International Residential Code', first printing, Chapters 2 through 24, 29, and 44 as published by the 'International Code Council, Inc.' is used as the basis of this document as is incorporated fully except as modified in italic herein." FILING HEADER AS PRINTED: "ACTION: Final DATE: 12/14/2018". RULE RECORD: EFF. 2019-07-01; PRIOR EFFECTIVE DATES 5/27/2006, 7/1/2007, 1/1/2008, 1/1/2009, 1/1/2013, 1/1/2015, 1/1/2016, 1/1/2018; AUTHORITY ORC 3781.10(A)(1), PROMULGATED UNDER ORC 119.03. *** DO NOT RECORD 2021 OR 2024. OHIO'S RESIDENTIAL CODE IS ON THE **2018** IRC, FIRST PRINTING, AND HAS BEEN SINCE 2019 - SEVEN YEARS, AND SIX CYCLES BEHIND ITS OWN COMMERCIAL SIDE'S NEC. · source ↗ |
| NEC — National Electrical Code (NFPA 70) | 2023 | NFPA 70-23 in OAC 4101:1-35-01 (2024 Ohio Building Code Ch.35 Referenced Standards), eff. 3/1/2024; and OAC 4101:8-44-01 (Residential Code of Ohio Ch.44 Referenced Standards), eff. 4/15/2024 (amended 70-17 to 70-23) · source ↗ |