§ 3105.18 Calculating Aggregate Floor Area as Fee Basis
   Except for electrical and mechanical permits, where aggregate floor area is the basis for establishing the amount of the permit fee, such aggregate floor area shall be calculated as follows:
   (a)   The aggregate floor shall be the sum of the gross horizontal areas of the several floors of the building or other structures, including interior balconies and mezzanines, if any, and including basements, cellars, and usable parts of attics; except that attic floors in dwelling houses and row houses shall not be included in the aggregate floor area unless they are at least fifty percent (50%) used for habitable rooms, kitchens, bathrooms, toilet rooms or for other similar living purposes;
   (b)   All horizontal dimensions shall be taken from the exterior faces of walls, including walls or other enclosures of enclosed porches, dormers, penthouses and sidewalk vaults, and including the areas of open porches and open porticos. The measurements shall not include the areas of outer or inner courts; or the areas of outside terraces, or steps, or of similar open structures outside of the enclosing exterior walls. The permit fee for structures outside the enclosing exterior walls of a building shall be based upon the estimated costs thereof established as hereinafter specified in Section 3105.19; provided that no permit fee shall be assessed for appurtenances such as outside terraces, steps, platforms and similar open structures, constructed on dwelling houses and row houses at the same time as such houses are built;
   (c)   Whenever a story height of a building exceeds fifteen (15) feet measured as herein specified for “H,” the aggregate floor area of such floor shall be deemed to be H/15 times the measured floor area thereof. “H” shall be the height measured from the floor level of such story to the floor level of the story above, or where such story is the uppermost story of the building and has a finished ceiling, shall be the height measured from the floor level of such story to a level one (1) foot above the average ceiling level within the measured floor area. Where no ceiling is provided in the uppermost story of a building and the roof is supported on girders or trusses, “H” shall be measured to the midheight of such girders or trusses; with sloping roof and no ceiling, “H” shall be measured to the mid- height of the sloping roof; with exposed roof joists on bearing walls, “H” shall be measured to a level one (1) foot above the average level of the roof joists;
   (d)   For all electrical and mechanical permit fees the aggregate floor areas shall be calculated as set forth in subsections (a) and (b) hereof.