The United States Department of Housing and Urban Development determines the building requirements for mobile homes, but these regulations are not the same as building codes that traditional homes need to meet. Mobile homes are generally not regulated by size but by how they are constructed.
Although most mobile homes are smaller than 5,000 square feet, owners can combine multiple models to create a larger home; the industry often uses the term "modular home" to classify these structures. While areas might not restrict the size of modular homes, lot size requirements might make it difficult to place a particular home in a mobile home park, since regulations might require a certain amount of lawn space that large homes might be too big to provide. In addition, individual parks might have a size limit.
Mobile homes are generally not regulated the same way as homes, and they were initially designed to skirt local building codes by being classified as vehicles. In an effort to avoid banning mobile homes outright, the federal government and state governments set laws pertaining to mobile homes, although most of these laws deal with taxation and zoning. Because mobile homes are almost always made by manufacturers, they typically don't need inspections the same way that homes do, although local laws vary significantly.