New Hampshire building code
New Hampshire has adopted 2024 IBC. The table below lists the governing edition for every discipline a plan check touches, followed by the New Hampshire cities and counties that amend it locally.
- Current edition
- 2024 I-Codes (IBC/IRC/IPC/IMC/IEBC/ISPSC) + 2018 IECC + 2023 NEC with NH amendments (all BCRB amendments approved as of 2025-10-10), effective 2026-07-01 per HB 1159 (2026), Chapter 49, signed 2026-05-08
- Prior edition
- 2021 I-Codes (IBC/IRC/IPC/IMC/IEBC/ISPSC) + 2018 IECC + 2023 NEC (effective 2024-07-01 per HB 1059 (2024); BCRB amendments as of 2025-04-11 ratified 2025)
- Code authority
- New Hampshire State Building Code Review Board (Office of Professional Licensure and Certification) with legislative ratification per RSA 155-A; NH State Fire Marshal / Board of Fire Control for the State Fire Code per RSA 153
Edition changeover: Projects with a complete application on or before 2026-06-30 may still be reviewed under the 2021 I-Codes (IBC/IRC/IPC/IMC/IEBC/ISPSC) + 2018 IECC + 2023 NEC (effective 2024-07-01 per HB 1059 (2024); BCRB amendments as of 2025-04-11 ratified 2025).
Adopted code by discipline
| Discipline | Adopted code | Local amendment |
|---|---|---|
| Building | 2024 IBC | n/a |
| Residential | 2024 IRC | n/a |
| Existing buildings | 2024 IEBC | n/a |
| Fire | 2021 NFPA 1 based on 2021 NFPA 1 (Uniform Fire Code) + 2021 NFPA 101 (Life Safety Code) | n/a |
| Electrical | 2023 NEC based on 2023 NEC (NFPA 70) | n/a |
| Mechanical | 2024 IMC | n/a |
| Plumbing | 2024 IPC | n/a |
| Energy | 2018 IECC | n/a |
| Accessibility | 2023 rules (Document #13674) NH Architectural Barrier-Free Design Code (Abfd 300) based on 2010 ADA Standards for Accessible Design, as modified by Abfd 303.02 | n/a |
Overlays that can apply
Mapped hazard and district overlays stack on top of the adopted code. These are the overlays recorded for New Hampshire. They apply by parcel, not jurisdiction-wide, so confirm the parcel before assuming one is in play. Check CAL FIRE's fire hazard severity viewer and FEMA's flood map service.
- FEMA mapped flood hazard area
Sources
- https://gc.nh.gov/bill_status/legacy/bs2016/billText.aspx?sy=2026&id=1843&txtFormat=html
- https://gc.nh.gov/bill_status/billinfo.aspx?id=1843&inflect=2
- https://gc.nh.gov/rsa/html/xii/155-A/155-A-1.htm
- https://gc.nh.gov/rsa/html/xii/155-a/155-a-mrg.htm
- https://gc.nh.gov/rsa/html/xii/153/153-1.htm
- https://gc.nh.gov/rules/state_agencies/saf-c6000.html
- https://gc.nh.gov/rules/state_agencies/abfd100-300.html
- https://www.nhmunicipal.org/sites/default/files/uploads/Guidance_Documents/changes-to-building-code-laws-in-2025-guide-municipalties.pdf
- https://www.portsmouthnh.gov/inspection/news/nh-building-code-and-fire-code-updates
- https://codes.iccsafe.org/codes/new-hampshire
- https://www.oplc.nh.gov/building-code-review-board
Common questions
What building code does New Hampshire use?
New Hampshire uses 2024 IBC. It is administered by the New Hampshire State Building Code Review Board (Office of Professional Licensure and Certification) with legislative ratification per RSA 155-A; NH State Fire Marshal / Board of Fire Control for the State Fire Code per RSA 153. The prior edition was 2021 I-Codes (IBC/IRC/IPC/IMC/IEBC/ISPSC) + 2018 IECC + 2023 NEC (effective 2024-07-01 per HB 1059 (2024); BCRB amendments as of 2025-04-11 ratified 2025).
Do cities in New Hampshire amend the state code?
Local amendments are adopted by ordinance at the city or county level. Confirm with the building department that reviews your permit.
Which edition applies to a permit already in review in New Hampshire?
Projects with a complete application on or before 2026-06-30 may still be reviewed under the 2021 I-Codes (IBC/IRC/IPC/IMC/IEBC/ISPSC) + 2018 IECC + 2023 NEC (effective 2024-07-01 per HB 1059 (2024); BCRB amendments as of 2025-04-11 ratified 2025).
Check a plan set against New Hampshire code
Knowing the adopted edition is the easy half. Architechtura reads your drawings, resolves which of these provisions actually apply to the project, and returns the corrections a plan checker would write up, each one cited to the section it came from.
Your first check is free, no card required.
Compiled from published state and municipal adoption ordinances. Local governments amend their codes on their own schedule, and a pending ordinance can change what applies to your permit. Confirm the governing edition with the building department before you submit. This page is reference information, not a code determination.