N.H. Rev. Stat. § 48-A:2
Whenever the governing body of any municipality finds that there exists in such municipality dwellings which are unfit for human habitation due to dilapidation, dangerous defects which are likely to result in fire, accidents, or other calamities, unhealthful lack of ventilation or sanitary facilities, or due to other unhealthy or hazardous or dilapidated conditions, including those set forth in RSA 48-A:7, power is hereby conferred upon such municipality to adopt ordinances, codes, or bylaws to cause the repair, closing, or demolition or removal of such dwellings in the manner provided in this chapter. Any municipality which adopts such a code or ordinance which has provisions for appeal, pursuant to this chapter, shall be exempt from any provisions of RSA 48-A which are in conflict with the adopted ordinance. The power conferred by this section shall not be used to impose any additional ordinances, codes, bylaws, licenses, certificates, or other restrictions on dwellings used as a vacation rental or short-term rental.
RSA 48-A:2
1959, 293:1. 1989, 89:1, eff. June 30, 1989. 2017, 249 : 7 , eff. July 1, 2017.