42 U.S. Code § 17071 - Energy Code improvements applicable to manufactured housing
Not later than 4 years after December 19, 2007, the Secretary shall by regulation establish standards for energy efficiency in manufactured housing.
The energy conservation standards established under this section shall be based on the most recent version of the International Energy Conservation Code (including supplements), except in cases in which the Secretary finds that the code  is not cost-effective, or a more stringent standard would be more cost-effective, based on the impact of the code  on the purchase price of manufactured housing and on total life-cycle construction and operating costs.
Any manufacturer of manufactured housing that violates a provision of the regulations under subsection (a) is liable to the United States for a civil penalty in an amount not exceeding 1 percent of the manufacturer’s retail list price of the manufactured housing.
 So in original. Probably should be “Code”.