Accessory dwelling units (ADUs) also known as guesthouses, companion units, granny flats or mother-in-law apartments, are separate housing units that can be attached to a main house or separated from it. An ADU has its own kitchen and bathrooms, meaning its tenants can be completely independent of those in the main house. Below are some things to know before building an ADU.
The number of new ADUs is growing fast, because homeowners are taking note that this is a great opportunity financially, as they can rent out smaller units to renters who don’t want to spend a lot on a place to live. They are also convenient, because they can house family when they come to visit, or their college grad children when they come home after school. However, you should be aware of a couple of things before you make a decision.
1. Legalities. Realize that zoning and building laws vary by depending on where you live. Each city or town has their own constructing and zoning laws, and they can differ dramatically one state to the next. It’s possible you might find that turning a shed or garage into a guest house saves more money and time later on than starting all over. You can find your city’s or town’s regulations online in order to get information on planning and building the space.
2. Some subdivisions and homeowners associations (HOA’s) don’t allow the building of ADUs at all. For example, while the town itself allows the home to be built, the suburb you live in may not. This is why it is very important to check before starting any construction.
3. You’ll want to hire an architect to do the job, or at least in the initial planning. Choose one that is experienced; an experienced architect will possess knowledge of the city’s laws regarding construction. For example, sometimes there are limits regarding property lines, the exterior aesthetics, and parking regulations. A great architect can also help you in the design of the construction.
4. Building an ADU is a construction job like any other. You will need to submit plans, get permits and follow all construction regulations. Your plans will need to incorporate standards addressing fire safety, water lines, sewer connections, distance from lot lines and many other considerations. Working with experienced and reliable architects, engineers and contractors at this stage is crucial.
When reading up on your locality’s building laws, you’ll likely discover restrictions on things like your ADU’s dimensions, required distance from property lines, general appearance and parking space requirements. Incorporate these in the initial design so you don’t have to make changes later.
Also consider people during this phase, specifically your guests or tenants, your neighbors and yourself. Will your parents be comfortable there? If so, add in senior-friendly design elements like ramps instead of steps. Will your neighbors object to an ADU that’s close to their property with windows facing them? If so, try skylights instead. Will you be happy with an ADU that blocks your favorite view or is too close to the main house? If so, reduce the size or change the location.