609.11.2, Pipe Installation Wall Thickness, is hereby deleted in its entirety and the following provisions shall be substituted therefor:

Hot water pipe insulation shall have a minimum wall thickness of not less than 1 inch (25 mm) for a pipe ½ inch (13 mm) up to 1 ¼ inch (32 mm) in diameter. Insulation wall thickness shall not be less than 1 ½ inches (37 mm) for a pipe of 2 inches (51 mm) or more in diameter, this can be reduced to 1 inch (25 mm) if piping is located within a partition within a conditioned space.