Codes
Manufactured (i.e. HUD code) homes are built to a federal building standard, the Federal Manufactured Home Construction Safety Standards.
(Factory built homes manufactured prior to the HUD code are referred to as "mobile homes") The HUD code regulates the design, construction, structural durability, transportability, fire resistance and energy efficiency of a home. It also prescribes performance standards for the mechanical, plumbing and electrical systems. Manufactured homes are built and shipped on a permanent chassis.
Modular homes are constructed to the same code as site-built homes with requirements set forth by state and local government for the specific locality. Various model building codes serve as the basis for most state code requirements. Examples include the International Residential Code (IRC), Uniform Building Code (UBC) and the National Electrical Code (NEC). Modular homes may be built on a permanent chassis or a returnable carrier system.
