Habitable rooms in existing one- and two-family dwelling buildings must have a clear ceiling height of at least seven feet. Habitable rooms in other existing buildings must have a clear ceiling height of at least seven feet six inches. The following height exceptions may be used for the one- and two-family dwelling ceiling height requirements:

1. A. Flat ceilings. Where the ceiling is flat, ceiling heights may be a minimum of six feet eight inches. Pipes, ducts, beams, or similar objects projecting from the ceiling may be as follows:
   1. 1. Ceiling projections may be as low as six feet where they are located within two feet from the wall; or
   2. 2. Ceiling projections may be as low as six feet two inches where they do not occupy more than 10 percent of the floor area in the room where they are located.
2. B. Sloped ceilings.
   1. 1. General. Where the ceiling is sloped, the height may be as follows:
      1. a. The minimum ceiling height must be at least six feet eight inches over an area comprising at least 50 percent of the overall room area; and
      2. b. Portions of the room with a ceiling height less than five feet may not be counted toward the overall room area.
   2. 2. Bathrooms. In bathrooms with sloped ceilings not more than 75 percent of the floor area of a bathroom is permitted to have a sloped ceiling less than seven feet in height, provided an area of 21 inches by 24 inches in front of toilets and lavatories has a minimum of six feet four inches in height. An area of 24 inches by 30 inches in front of and inside a tub or shower must have a minimum of six feet four inches in height.
3. C. These exceptions to the current building codes do not apply where any occupancy has been changed, or the occupant load has been increased, contrary to the provisions of this Title.