For the purpose of natural lighting, any room is permitted to be considered as a portion of an adjoining room where one-half of the area of the common wall is open and unobstructed and provides an opening of not less than one-tenth of the floor area of the interior room or 25 square feet (2.32 m2), whichever is greater.
1.2. Has a ceiling height of not less than 7 feet (2134 mm); and
1.3. Has a longer side at least 65 percent open and unobstructed.