To find building codes, you may need to check at the local, state, and federal levels. The state building code sets the minimum standards for the state, but local governments can have more stringent standards. Federal standards may also apply in some situations.
The "New Hampshire building code" (or "state building code" or “building code of the state of New Hampshire”) is really several codes as adopted by the State of New Hampshire (RSA 155-A) and amended by administrative rule (Bcr 300). The "New Hampshire fire code" or "state fire code" is also several codes as adopted by the state of New Hampshire (RSA 153) and are amended by administrative rule (Saf-C 6000).
Many states, New Hampshire included, adopt "model codes" and then adapt them for their own use. That's why it's never enough just to read the model code. You must also look for any state or local amendments to the model code and read them together.
There are many other codes: commercial building codes, historic structure codes, cultural resources codes, fuel gas codes, etc., that may have been adopted by a particular municipality so to be sure to check the town or city’s website. Start by looking for the code enforcement department or its equivalent. We’ve found it under various names: code enforcement, code administration, building department, or building inspection to name a few. Look for something along the lines of “current codes enforced.” For some towns, we had to look at the building permit application documents to figure out what codes those towns were enforcing. Check the ordinances as well, but be careful because many of those are out of date. You may see references to building codes, but some municipalities never updated their ordinances when the state building code was enacted in 2002. If the ordinances refer to building standards that are much older than the state’s current versions, keep looking.
Please remember that this guide is for information purposes only and is not comprehensive. It is intended as a starting point for research, to illustrate the various sources of the law, and to provide guidance in their use. NH Law About ... is not a substitute for the services of an attorney.