The photo to the left is of a home I sold a few years back. You cannot tell from the image, but there is a front door off to the right of the single car garage door, and back around on the left side, near the double car garage door, there’s another front door. It is a duplex or a duet home? You cannot necessarily tell by looking!
A duplex is a multifamily home, in the same category as a triplex of four plex, meaning there are multiple attached living units. But what is truly distinctive is the way they are bought and sold. With multifamily homes, such as a duplex, all of these dwellings are sold together. (The units are not sold separately.) So if you buy a duplex, you get both sides. If you buy a triplex, you get three units. Sometimes an owner will live in one of the homes and renters are in the rest. Many times, though, all of these multifamily homes are entirely leased out. (Duplexes are usually 1 story and many of the duplexes in the San Jose area were built in the 1950s and 1960s, but you cannot tell from looking at it what the zoning and class of housing are with certainty.) These types of properties are considered income producing or investment properties.
With duet homes, each side is sold separately. Most of the time they are 2 stories, younger, and both sides are owner occupied and they are considered “attached single family homes” while a house is usually a “detached single family home”. Although just as with a house, there could be a tenant in a duet home, it is not presumed to be an investment property.
Is it possible to change the zoning and classification of housing? Can a duplex become a duet home? Possibly. Sometimes owners will work to change the classification of the property. We see it especially with some former 4 plex places, McKeon built, which have been changed to condo ownership so that instead of one 4 plex, 4 distinct homes are sold (four condominiums). So it changes from class 3 to class 2 (condos and townhomes). In Los Gatos, I knew of someone who purchased a parcel with two small houses on it and although they were not attached, they were “detached duplexes”. I’d never seen that before! Wisely, the owner of these two worked hard to change the classification and do a lot split – now there are 2 houses on 2 parcels and they are both single family homes, and worth more too.