Class A motor homes are defined as those homes constructed on a commercial truck or bus chassis. Some Class A motor homes are constructed on large purpose-built platforms as well. Most Class A motor homes resemble buses in both style and size, making them among the largest motor homes available.
Motor home classes are distinguished on the basis of the type of chassis underlying a motor home. The use of a large truck or bus chassis distinguishes Class A motor homes from Class B motor homes, which are built on cargo or passenger van chassis, as well as from Class C motor homes that are constructed based on a pickup truck chassis. Towed trailers, such as camper trailers and fifth-wheel trailers, are not classified under the motor home class system.
The primary advantage of using a truck or bus chassis as the basis of a Class A motor home is that it permits the motor home to be much larger than that of a Class B or Class C motor home. The large size of Class A motor homes not only allows them to have more interior space than other classes of motor home, but to have additional luxury amenities that are not available in smaller configurations. Many Class A motor homes incorporate slide-out sections that dramatically increase the interior space of the motor home when it is parked.