They're more commonly referred to (on this site and in much literature on the subject) as accessory dwelling units, or ADUs, which is their legal and regulatory name. You may have also heard of them under other names, including: Accessory apartment. Basement apartment. Ancillary unit.
Mother-in-law suites are also known as in-law apartments, granny flats, or accessory dwelling units (ADUs). Although the name implies housing for an aging parent, mother-in-law suites have many different purposes that can work with your unique situation.
Background. Naming conventions vary by time-period and location but secondary suites can also be referred to as an accessory dwelling unit (ADU), mother-in-law suite, granny flat, coach house, laneway house, Ohana dwelling unit, granny annexe, granny suite, in-law suite, and accessory apartment.
A mother-in-law unit is often integrated into the main house. That means it may not have its own entrance like other ADUs. The square footage of an ADU is not added to the square footage of the main house. Most mother-in-law units are part of the overall house and added to its square footage.
Terms such as “master bedroom,” “mother-in- law suite,” and “bachelor apartment” are commonly used as physical descriptions of housing units and do not violate the law.
Examples of Familial Status Discrimination
Requiring families with children to live on specific floors or in specific buildings or areas. Imposing overly restrictive rules about children's use of the common areas (e.g., pools, hallways, open spaces) Advertising that prohibits children.
Two women who are mothers-in-law to each other's children may be called co-mothers-in-law, or, if there are grandchildren, co-grandmothers.
There may be tax credits for having an ADU or in-law suite. For instance, if you're paying for more than half of your relative's support, you may be able to claim them as a dependent. You may also qualify for a home office tax deduction if that's the in-law suite's primary use.
Space Limitations
While they offer a more affordable living option, ADUs can feel cramped and may not be suitable for large families or those who need a lot of space.
According to Porch.com, when ADUs are located on properties in major cities with high housing costs, an ADU can add as much as 35% to the value of a property.
If you have kids, you'll end up calling your mother-in-law by her anointed grandmother name—Grandma, Gams, GiGi, MawMaw, or Grams—she'll love it. It's great to get on a first-name basis with your mother-in-law. Calling your MIL by her first name is a popular way to go, and most daughter-in-laws do it…
Chances are, as a California resident, you've heard of backyard houses before, though you may not have heard them referenced under that name. The legal and regulatory name for backyard houses is accessory dwelling unit, or ADU.
An in-law suite is the most common name for a small, apartment-like space on the same property as, or even attached to, a single-family home. These dwellings are living spaces usually equipped with a bedroom, bathroom, kitchen and a separate entrance from the primary residence.
Whether it's the “casita,” “granny unit,” or “mother-in-law suite,” there's a second unit for everyone. Additional living spaces are great for those who want to live in one space and rent the other.
Building a mother-in-law suite could also offer certain tax benefits. How many square feet is a typical mother-in-law suite? Mother-in-law suites can vary in size but are typically about 500 square feet.
If you know the unit will sit vacant for a while, an in-law unit can be turned into a more traditional rental, with long-term monthly or even yearly leases.
ADU opponents said that ADUs would create parking problems, bring down property values (and generally bring in undesirable people), create overcrowding, change the appearance of neighborhoods, generate noise and garbage, and perhaps end the single-family nature of existing neighborhoods.
A Detached Accessory Dwelling Unit (DADU) involves building a small, single-family residence on a property with an existing residence.
They can be converted garages, basement apartments, or separate cottages. ADUs allow homeowners to expand their living space and generate rentals while maintaining the privacy of both units. On the other hand, tiny houses are compact living spaces intentionally designed to be small and efficient.
Despite its specificity, the term “mother-in-law suite” is sometimes used interchangeably with “guest house.” That said, guest houses are generally detached from a primary residence, while mother-in-law suites may be attached to it.
The potential dependent must be one of these: Your parent, ancestor (ex: grandparent, great-grandparent), or sibling of either of them. Stepsibling, stepparent, parent-in-law, son- or daughter-in-law, or brother- or sister-in-law. Any person that lived with you for the entire year as a member of your household.
Home renovations typically do not qualify for federal tax deductions, but certain improvements may qualify for deductions and credits can help reduce taxes. Financing home improvements through your mortgage may allow you to claim the interest as a mortgage interest deduction.
While some call her "mom," others call her by her first name or something else entirely. Some approached the topic with a discussion, some started saying the name naturally and some still aren't comfortable with the idea yet—there are no right or wrong answers.
The Yiddish term for the parents of your son or daughter in law is "Machatunim" (plural). The singular female is "Machatainista"; the singular male is "Machitin".
Deciding Whether to Care for Your In-Laws
Ultimately, it's up to you to decide how much you want to participate and set the appropriate boundaries.