While attached ADUs don’t offer the same degree of privacy as detached ADUs, they still offer more privacy than ADUs created from interior conversion. Additionally, attached ADUs benefit greatly from expanding upon the existing plumbing and electrical systems of the home.
However, like building a detached ADU, building an attached ADU is an expensive endeavor. It also requires land, though not as much as a detached ADU.
Interior conversion ADUs transform existing living space to offer a dramatically less expensive ADU option. This choice often only requires limited permitting and minor changes to comply with complete ADU regulations.
Additionally, it can share the primary residence’s amenities, further lowering expenses and construction hassles. However, converted space ADUs save money at a sacrifice, as they offer the least amount of privacy.
On the other hand, an exterior converted ADU offers the benefit of additional privacy. Oftentimes this form of an ADU can expand upon an existing home system. However, while it is less expensive than a new construction project, it does clock in as more expensive than an interior ADU conversion.