A common confusion is thinking a twin home is the same as a duplex. A twin home looks like duplex, walks like a duplex, but doesn’t act like a duplex. Twin homes do look like duplexes, and do have a shared common wall but the main difference is the ownership interest. A twin home has an individual owner who has rights and responsibilities for their own side and for their own lot. In other words, twin homes are basically half-homes with with their own respective lot with a lot line landing between the two homes.
Duplexes are two properties on one lot. You can have duplexes that have different owners but they have a condo ownership interest meaning that there is shared lot ownership.