The Factory Built Homes Institute and industry trade association state that factory built homes are constructed using the same materials as the site-built homes. factory built homes can last as long as site-built housing. “The Factory Built Home Living News” hosts a video of a factory built home surviving a tornado. This home was first hit by a tornado and then was subjected to high substance wind of 105 mph for over half an hour. This was visual evidence of how strongly the factory built home is when it is properly installed. The only thing that was lost was a few roof shingles. In addition, it has been proven that modern factory built homes are stronger by design than homes built using conventional methods.