New Hampshire building code

Codes in force in New Hampshire

Each code family with the edition and the date it took effect, as the adopting agency or statute states them.

Scope, amendments and transition rules

Energy code, residential

Scope

Statewide; local amendments not allowed²

Applies to

Every municipality statewide; local enforcement is by municipal choice¹

Local amendments allowed?

Administrative only¹

Energy code, commercial

Scope

Statewide; local amendments not allowed²

Applies to

Every municipality statewide; local enforcement is by municipal choice¹

Local amendments allowed?

Administrative only¹

National Electrical Code (NEC)

Scope

Statewide; local amendments not allowed²

Applies to

Every municipality statewide; local enforcement is by municipal choice¹

Local amendments allowed?

Administrative only¹

State code

Scope

Statewide minimum; local governments may go further³

How New Hampshire adopts building codes

RSA 155-A:1, IV; 155-A:2; 155-A:3; 155-A:10

• Either code during concurrency. This requirement notwithstanding, for a period of 6 months after the effective date of the code adopted under RSA 155-A:1, IV, a concurrency period is established, allowing building permits, and other required documents, at the election of the applicant, to 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.²
• Code at application stays in effect. The state building code in effect at the time that the application for the building permit required by RSA 155-A:4 is received by the governing authority shall remain in effect for the duration of the work covered by that permit.²
• Municipal enforcement requires an ordinance. A municipality that chooses to enforce the state building code is required to adopt an ordinance which is required to be confirmed by the Building Code Review Board.¹
• State Building Code Review Board review, ratified by the legislature. Statewide amendments to the state building code shall be reviewed and approved by the board, then submitted annually to the legislature for ratification by the adoption of appropriate legislation before they become effective.²

Applies to

Every municipality statewide; local enforcement is by municipal choice¹

Can local rules be stricter?

No technical amendments²

What local governments may change

RSA 155-A:3, VII · in effect July 1, 2026²

• Local deviation prohibited. Notwithstanding any other provision of law, no local legislative body shall enact or enforce any ordinance, adopt or enforce any rule, or implement any regulation that amends, overrides, or deviates from the state building code, or addresses any subject included in the state building code, except as otherwise permitted by this section or other statute, on or after the effective date of this section.²
• No residential sprinkler mandates locally. No municipality or local land use board, as defined in RSA 672:7, shall enforce any ordinance, regulation, code, or administrative practice requiring the installation of automatic fire suppression sprinklers in any new or existing detached one- or two-family dwelling unit in a structure used only for residential purposes, or in existing buildings that contain, or will contain, no more than four dwelling units, unless fire sprinklers are existing or are required by a nonresidential occupancy.²

For permits, exemptions and owner-builder rules, see New Hampshire building permits. To compare editions across states, see the code adoption map.