Roofing in Portsmouth, New Hampshire

The 2024 International Residential Code, as adopted by the State in the New Hampshire State Building Code. RSA 155-A:1, IV defines the state building code as "the adoption by reference of" the 2024 editions of the International Building, Existing Building, Plumbing, Mechanical, Swimming Pool and Spa, and Residential Codes, the 2018 International Energy Conservation Code and the 2023 National Electrical Code, "including all amendments reviewed and approved by the board as of October 10, 2025, and ratified by the legislature in accordance with RSA 155-A:10." That edition has applied since July 1, 2026. For six months after a new code takes effect, RSA 155-A:2, I lets a permit applicant show compliance "using either the code in effect just prior the effective date of the code adopted under RSA 155-A:1, IV, or the code adopted under RSA 155-A:1, IV, but not a combination of the 2 codes"; the code in effect before was built on the 2021 International Residential Code. The State's amendments to the 2024 code replace its Chapter 1 with a State administrative chapter and change no section of Chapter 8, Roof-Ceiling Construction, or Chapter 9, Roof Assemblies. The code reaches existing houses: "All buildings, building components, and structures constructed in New Hampshire shall comply with the state building code and state fire code," and "the alteration, renovation, rehabilitation, repair, removal, or demolition of all buildings and structures previously erected shall be governed by the provisions of the state building code" (RSA 155-A:2, I). It applies in every city and town: the code "shall be effective in all municipalities ... without further local modification, except as permitted by this section" (RSA 155-A:3, VII). A city or town may amend only the code's administrative provisions, such as permits and fees, and those amendments are not enforced unless the State Building Code Review Board confirms them: "No amendments to the technical requirements of the state building code are permitted" (RSA 155-A:3, II). Enforcement is local and set up by each city or town: its legislative body "is hereby empowered and authorized to establish a local enforcement agency" (RSA 155-A:3, I). Where a city or town has no local enforcement agency or contracted third party, "the state fire marshal or the state fire marshal's designee may enforce the provisions of the state building code and the state fire code ... upon written request of the municipality" (RSA 155-A:7, I). Everything above is New Hampshire state law, the same in every city and town. In Portsmouth the Inspection Department in City Hall, 1 Junkins Avenue, enforces the code, and the city's own page says applications for building permits are issued through the Inspection Office.