All leased or rented housing in New Hampshire must, by law, meet certain minimum standards to be considered livable. Whether you have a long-term lease or a month-to-month rental, there is an "implied warranty of habitability" by the landlord that your residential rental is habitable and fit for living. If it is not, there are steps that you can take to make sure your landlord repairs and maintains the premises.
You will need to look at your local town or city ordinances as well as state law to find out what the minimum standards for livability are in your area.
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.