A pre-constructed home built prior to the enactment of the HUD Code on June 15, 1976.
A “manufactured home” means any pre-constructed building unit or combination of pre-constructed building units that:
(a) Include electrical, mechanical, or plumbing services that are fabricated, formed, or assembled at a location other than the site of the completed home;
(b) Is designed for residential occupancy in either temporary or permanent locations;
(c) Is constructed in compliance with the federal act, factory-built residential requirements, or mobile home standards;
(d) Does not have motor power; and
(e) Is not licensed as a recreational vehicle.
The Federal Manufactured Home Construction and Safety Standards Act referenced in section (c) is commonly called the HUD Code, which went into effect June 15, 1976.
A pre-constructed building unit or units built in compliance with the site-built home standards of the regional, state, or local building code used by the government unit which the house is to be located. Commonly, this is the IRC code.
The only definitive way to tell the difference between a HUD code or a modular is the labeling. Someone may tell you that there are tricks to the trade, such as if there is a chassis then it is a HUD code home. This is not necessarily true. Some modulars are built on a metal frame and some HUD code homes built in the 1980s do not have a metal frame. So be sure to check the labels, because looks can be deceiving.