First, some distinctions: Site built and stick built home usually refers to a traditional single-family residence that is built at the same site on which the finished home will stand. It is built by a local building contractor according to local construction codes.
Next, forget the term “mobile home” – they’re now called “manufactured” homes, some of them 2,500-square-foot structures with sun rooms and decks. The Manufactured Housing Institute defines a manufactured home as "a single-family house constructed entirely in a controlled factory environment, built to the federal Manufactured Home Construction and Safety Standards, better known as the HUD Code" with a permanent chassis for transportability. Most people still refer to them as mobile homes, but the MHI says that "mobile home" is the term used for homes built prior to June 15, 1976, when the HUD Code went into effect.
Twenty-five percent of new residential construction and home sales annually in the U.S. are manufactured homes. One reason: this is the lowest cost stand-alone residence available. You can purchase a brand new single-section manufactured home for less than $29,000!
There are a few drawbacks, of course. One is that many communities do not allow manufactured homes and another is potentially costly insurance, thanks to perceived risks to manufactured homes such as wind and fire damage.
Like manufactured houses, modular homes are built in a factory and quality inspected every step of the way. Unlike manufactured homes, the pieces (“modules”) of the house are transported to the building site where they are put together by a local building contractor, and they have no chassis or wheels. Since all work is done indoors, there is no weather damage or delay. Some floorplans can be built in the factory in as little as one to two weeks, and two to four more weeks to attach the modules to a concrete foundation, hook up utilities and complete the home.
Unlike manufactured homes, modulars must conform to building codes in your specific location. And while they do cost more than manufactured homes in general, they usually cost less per square foot than for a comparable site-built house and are extremely energy efficient. Few communities have restrictions against modulars other than size requirements.
Modular housing may be the wave of the future. It accounts for 60 percent of all residences in Sweden and 30 percent in Japan.