No person shall occupy, lease to any other person, or permit any other person to occupy, a building or any part of a building as a dwelling house, office, store, shop, theater, public hall, sleeping apartment or tourist cabin, unless such building shall have readily accessible adequate toilet and lavatory facilities, properly ventilated and constructed, and kept in proper sanitary condition; and unless said building shall be provided with suitable drains or sewers for conveying waste water and sewage away from the premises into some public sewer, if there be one within 100 feet thereof, and if not, for conveying it away underground or in some other manner that will not be offensive. The phrase “public sewer”, as used in this chapter, shall be understood to mean any sewer constructed and maintained by taxation, or any sewer which is open for general use upon the payment of a rental, license or other fee. Notwithstanding the provisions of this section, privies (outhouses not conveying sewage by water) may be allowed if such facilities are first approved by the local municipal health officials as to location and construction of the facilities. At the option of the local municipal health officials, further approval may be required by the department of environmental services, prior to the construction of such facilities. Nothing in this section shall prohibit cities, towns, or village districts, by ordinance or by regulation under N.H. Rev. Stat. § 147:1, from increasing the 100-foot distance contained in this section, or from granting waivers to the requirement of connection to the public sewer for properties with adequate alternative sewage disposal systems which comply with applicable state and local regulations, designed by a designer licensed in New Hampshire and approved for construction by the New Hampshire department of environmental services after January 1, 1985.