Accessory dwelling units (ADUs), also known as granny flats or in-law units, are small, standalone residential structures that are built on the same property as a larger primary residence. Prefab ADUs are ADUs that are built offsite and then transported and assembled on the property. Prefab ADUs offer several benefits, including being faster and more cost-effective to build than traditional ADUs. They can also be more energy-efficient and sustainable, as they are often constructed using prefabricated materials that are designed to be energy-efficient. Prefab ADUs can be used for a variety of purposes, including as a rental unit, a home office, or a place for aging family members to live. In some areas, there are specific rules and regulations that govern the construction and use of prefab ADUs, so it is important to familiarize yourself with these regulations before embarking on a prefab ADU project.