New Hampshire State Building Code

The State of New Hampshire has adopted building codes which govern both residential and non-residential structures. Effective July 1, 2026, NH State Building Code uses the 2024 International Residential Code (IRC) and the 2024 International Building Code (IBC) as base standards for the State codes for residential and non-residential structures, respectively. There are other code standards which govern non-structural areas of design, all of which can be found at the State of NH Building Code website. Statewide Amendments to the Codes are published here. 

The 2024 IBC references ASCE 7-22, “Minimum Design Loads for Buildings and Other Structures”, for snow loads in the state.  Structural Engineers can expect to see significant changes in the way that snow loads are calculated with this new code adoption.  The specific case studies for cities, towns and unincorporated townships in the state, previously made available through the publication “Ground Snow Loads for New Hampshire”, US Army Corps of Engineers, ERDC/CRREL TR-02-6, February, 2002 no longer applies to the way snow loads are calculated or developed in the state. The new methodology for determining snow loads through ASCE 7-22 is based on reliability-targeted loading.  These new ground snow loads can be found with contour maps in ASCE 7-22 or through ASCE’s Hazard Tool at http://www.ascehazardtool.org.  SENH reminds those not familiar with how snow loads are used in design, that the ground snow load is only the starting point for determining the snow loads actually applied to a structure.

Not every community in New Hampshire has building code enforcement officials. (In those municipalities the State Fire Marshal’s Office enforces the code.) This does not relieve the owner or design professional from meeting the requirements of the NH State Building Code in those communities without local code enforcement.