Every door opening into an attached garage other than an exterior door, shall be tight fitting and of one and three-eighths inch solid slab wood or equal construction. Stairs may be of wood in residential construction and need not be closed. Stairs shall be not less than thirty-six inches in width. Each interior stairway shall have a head clearance throughout of not less than six feet, six inches. (Ord. 1977-10 § 6-10, 1977)