Some counties welcome barndominiums, but metro and suburban areas may restrict them.
State code adopted but enforced locally. Towns may adopt the state code or a less restrictive local code.
Primary Code
NH State Building Code
Code Version
2018 IBC / 2018 IRC with NH amendments
Adoption Level
Statewide + Local Amendments
Statewide Enforcement
No
Varies by town. Some rural towns have limited enforcement.
Residential
Required
Commercial
Required
Agricultural
Not Required
Size threshold: structures under 200 sq ft may be exempt.
Agricultural buildings may be exempt in some towns.
Small structures may be exempt.
Heavy snow loads, especially in the White Mountains. Moderate wind.
Wind Load
100–130 mph
moderate zone
Snow Load
40–80 psf
Seismic
A–B
Category
Flood
FEMA Regulated
Energy Code
IECC
Version
2018 IECC
Energy code enforcement varies by town.
License Type
No state license required
New Hampshire does not require a state contractor license.
Front
25–40 ft
Side
10–20 ft
Rear
15–25 ft
Varies by town.
Frost depth 48-60 inches. Basements are standard.
Popular in rural areas.
Agricultural exemptions may apply.
Limited acceptance. Some rural towns are more flexible.
Snow load engineering important.
Full code compliance where enforced.
HOAs uncommon in most of New Hampshire. Some lakefront communities have deed restrictions.
Riverine flood zones along major rivers.
Verify the information above directly from these official sources. Regulations change — always confirm with your local building department before starting construction.
Disclaimer: This guide is for informational purposes only and does not constitute legal or professional advice. Building codes, permit requirements, and zoning regulations change frequently. Always verify current requirements with your local building department, planning office, or a licensed professional before starting construction. Homestead Steel Structures & Design is not a legal authority on building codes or zoning regulations. Last updated February 2026.
