Habitable spaces, hallways, corridors, laundry areas, bathrooms, toilet rooms and habitable basement areas shall have a clear ceiling height of not less than seven (7) feet (2134 mm). (404.3)
Exceptions:
(A) In one- and two-family dwellings, beams or girders spaced not less than four (4) feet (1219 mm) on center and projecting not more than six (6) inches (152 mm) below the required ceiling height.
(B) Basement rooms in one- and two-family dwellings occupied exclusively for laundry, study or recreation purposes, having a ceiling height of not less than six (6) feet eight (8) inches (2033 mm) with not less than six (6) feet four (4) inches (1932 mm) of clear height under beams, girders, ducts and similar obstructions.
(C) Rooms occupied exclusively for sleeping, study or similar purposes and having a sloped ceiling over all or part of the room, with a clear ceiling height of at least seven (7) feet (2134 mm) over not less than one-third (1/3) of the required minimum floor area. In calculating the floor area of such rooms, only those portions of the floor area with a clear ceiling height of five (5) feet (1524 mm) or more shall be included.