The study found that the habitable life of new, year-round occupied manufactured homes is 55.8 years. When other categories of manufactured housing are factored in, such as vacant and seasonal housing, the habitable life jumps to 71.4 years. The National Association of Homebuilders says that the average age of all site-built houses is currently 28 years. The average age of all manufactured houses in existence today is 21 years. But as in all construction, the key to a home's longevity is proper maintenance.
Simple upkeep can add many years to the life of both site-built and manufactured housing.
Manufactured homes do not appreciate in value like other forms of housing. Instead, manufactured homes depreciate in market value, similar to the way automobiles lose value each day. While there is no one easy answer, recent data seems to suggest that manufactured homes can appreciate just like other forms of housing. Datacomp Appraisal Systems recently completed a study in Michigan that looked at 185 manufactured homes in Michigan, comparing the average sale price when new to the average resale price several years later. The only accurate conclusion is that some homes appreciate and some don't.