(a) Except as provided in subsection (h) of § 29-252a, no building or structure erected or altered in any municipality after October 1, 1970, shall be occupied or used, in whole or in part, until a certificate of occupancy, as defined in the regulations adopted under § 29-252, has been issued by the building official, certifying that such building, structure or work performed pursuant to the building permit substantially conforms to the provisions of the State Building Code and the regulations lawfully adopted under said code. Nothing in the code or in this part shall require the removal, alteration or abandonment of, or prevent the continuance of the use and occupancy of, any single-family dwelling but within six years of the date of occupancy of such dwelling after substantial completion of construction of, alteration to or addition to such dwelling, or of a building lawfully existing on October 1, 1945, except as may be necessary for the safety of life or property. The use of a building or premises shall not be deemed to have changed because of a temporary vacancy or change of ownership or tenancy.

(b) No building official shall refuse to issue a certificate of occupancy for any single-family dwelling because such dwelling is not connected to an electric utility if such dwelling is otherwise in conformity with the requirements of this section and applicable local health codes and is equipped with an alternative energy system. A certificate issued under this section shall contain a statement that an alternative energy system is in place. For the purposes of this subsection, “alternative energy system” means any system or mechanism which uses solar radiation, wind, water, biomass or geothermal resources as the primary source for the generation of electrical energy.

(c) Nine years from the date of issuance of a building permit issued pursuant to § 29-263 for construction or alteration of a one-family dwelling, two-family dwelling or structure located on the same parcel as a one-family dwelling or two-family dwelling, for which construction or alteration a certificate of occupancy, as defined in the regulations adopted pursuant to § 29-252, has not been issued by the building official, such building permit shall be deemed closed. Following such nine-year period, no enforcement action based upon work commenced or completed pursuant to an open building permit shall be commenced. No municipality or officer or employee of any such municipality shall be liable concerning any claim relating to the closure of a building permit pursuant to this section. For the purposes of this section, “structure” has the same meaning as in the zoning regulations for the municipality in which the building permit was issued, or if undefined by such regulations, “structure” means any combination of materials that is affixed to the land, including, but not limited to, a shed, garage, sign, fence, wall, pool, patio, tennis court or deck.