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 area 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 the 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 used for habitable rooms, kitchens, bathrooms, toilet rooms or 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 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 1703.60, 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 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 above 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 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, with sloping roof and no ceiling, “H” shall be measured to a level one foot above the average level of the roof joists.
(Ord. 178-1959.  Passed 9-14-59.)