Under NH State Law (RSA 155-A), the State of NH utilizes and adopts a suite of Codes published by the International Code Council. The current editions and amendments can be found here.
Additionally, Bow has its own amendment to the IRC. Under Bow Ord. §14.01, the town amends IRC §R310.1 to add, “In newly constructed buildings where a door opening having a threshold below the adjacent ground elevation serves as an emergency escape and rescue opening, a bulkhead enclosure and bulkhead door shall not be permitted. Homes constructed after the effective date of this ordinance shall have an at-grade basement access, other than through a garage, in the form an enclosed structure with an at-grade, vertical hung door opening inward.”