As used in sections 81-1608 to 81-1626, unless the context otherwise requires:

(1) Department means the Department of Environment and Energy;

(2) Contractor means the person or entity responsible for the overall construction of any building or the installation of any component which affects the energy efficiency of the building;

(3) Architect or engineer means any person licensed as an architect or professional engineer under the Engineers and Architects Regulation Act;

(4) Building means any new structure, renovated building, or addition which is used or intended for supporting or sheltering any use or occupancy, but not including any structure which has a consumption of traditional energy sources for all purposes not exceeding the energy equivalent of three and four-tenths British Thermal Units per hour or one watt per square foot;

(5) Residential building means a building three stories or less that is used primarily as one or more dwelling units;

(6) Renovation means alterations on an existing building which will cost more than fifty percent of the replacement cost of such building at the time work is commenced or which was not previously heated or cooled, for which a heating or cooling system is now proposed, except that the restoration of historical buildings shall not be included;

(7) Addition means an extension or increase in the height, conditioned floor area, or conditioned volume of a building or structure;

(8) Floor area means the total area of the floor or floors of a building, expressed in square feet, which is within the exterior faces of the shell of the structure which is heated or cooled;

(9) Nebraska Energy Code means the 2018 International Energy Conservation Code published by the International Code Council;

(10) Traditional energy sources means electricity, petroleum-based fuels, uranium, coal, and all nonrenewable forms of energy; and

(11) Equivalent or equivalent code means standards that meet or exceed the requirements of the Nebraska Energy Code.