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mother-in-law apartment

You’ve finally got it - the perfect home. Everything just as you imagined it, with things that fit snugly into their spaces and just enough room for everyone. That is, until you have to host someone! A mother-in-law apartment deals with that problem effortlessly, as well as giving you a host of other benefits. Whether you’re looking at constructing a mother-in-law apartment or moving into a home with one, read our guide first, that covers what is a mother-in-law apartment as well as everything else about it.


What is a Mother-In-Law Apartment?

Tracing its name to the age-old strained relationship between couples and their parents-in-law, a mother-in-law apartment is an accessory dwelling unit (ADU) - a separate living space. Also known as mother-in-law suites and granny suites, mother-in-law apartments can either be attached to the house, or be a standalone on the same property, like a tiny cottage. It normally comes with at least a bedroom and a bathroom, but some even have further comforts like a living room, a kitchen or a kitchenette and a separate entrance.

The name suggests that it is used to allocate an unwanted someone to the room to keep them at an arm’s distance. However, families are using mother-in-law apartments for those looking to balance their privacy and autonomy while still living with and being supported by a family, like an aging parent or a University-returned kid. Statistics show an 8% rise in the number of Americans living with two or more adult generations in a single household from 1980 to 2019, bringing the figures from 12% to 20%. What’s in a name after all?

For those with no familial obligations or real use for the mother-in-law apartment, it makes for a great asset: renting it out and earning a little extra income.

How are Mother-In-Law Apartments Added?

One of the most common ways that families built a mother-in-law apartment is by renovating pre existing space in the house, typically underutilized. Garage spaces and basements are often converted into mother-in-law apartments, and sometimes offer the benefit of separate entrances. The same can be said of a bedroom at the back of the house; by creating a door with a key, the person in-residence can come and go without disturbing the rest of the household.

Alternatively, a separate ADU can be constructed on the property itself. The mother-in-law apartment can then come equipped with a small kitchen and a living room as well, provided there is the space for it. Separate entrances is a given.

Benefits of a Mother-In-Law Apartment

Multi-generational utility: Adult children with aging parents turn to mother-in-law apartments as a much cheaper alternative to nursing homes and other long-term care. With the children being primary caregivers, parents feel secure with the familiarity, and the costs of a nursing home or a full-time hire are eliminated. When grandchildren come along, grandparents can babysit when the parents are at work or otherwise occupied, strengthening their bond with the tiny tots.

Work-from-home advantage: A mother-in-law apartment is also very advantageous for anyone who works from home. Working from home often requires a designated spot with as minimal interruption as possible - something that is not very doable in several homes. Converting your mother-in-law apartment into a workspace gives you the perfect privacy you need. Once work hours are done, simply step out of the suite and into your house. The scales can finally be even for that much-revered work-life balance.

Additional income: As mentioned, an unused mother-in-law apartment can be rented out, earning you some extra cash. Better yet, if you live in a relatively popular or touristy destination, you can list it up on sites like Airbnb. Steadily gaining preference over hotels, Airbnbs are the new thing and if your location is ideal, you could turn in a pretty amount with it. Just make sure to keep it clean and well-equipped. Use it as a guesthouse for relatives and friends when it isn’t being occupied.

Storage space: Perhaps you live in a house with a mother-in-law apartment, or are looking into one… always remember that a mother-in-law apartment can double up as storage space if it's going unused. Not only can your knickknacks go in there, but you can also furnish it with the extra furniture and household items you’d rather pack away into a box.

Increase in property value:  With more and more people seeking out multi-generational housing, a mother-in-law apartment can actually add a significant amount of value to your property. Firstly, the extra square footage added to your primary house will lead to a higher listing price.

Secondly, the extra space is particularly attractive for large families, those looking to have a relative or parent move in, or those who find the rent income appealing. In fact, a National Association of Realtors survey showed that 33% of buyers would pay nearly $3,000 more for the mother-in-law apartment. According to the study, “a finished basement and in-law suite were the two most desired aspects of a home that buyers would be willing to pay more for.”

Downsides of a Mother-In-Law Apartment

Increased utility costs: There’s no denying that mother-in-law apartments come with a rise in utility costs, since the utilities for the apartment go hand in hand with the costs of the main house. This means extra energy, heating, water and cooling.

Upkeep: If the apartment is a standalone type, you have the added cost of upkeep over the utilities. While a standalone has the benefit of complete privacy, it also means you have an entire set of walls and windows and a separate roof and landscaping to look after. More lightbulbs will have to be replaced, and there’s one more bathroom that needs constant plumbing checks.

Restrictions on construction: Constructing a mother-in-law apartment means navigating the maze of zoning codes and city building regulations.

Restrictions on rent: Apart from looking into things like landlord insurance, you may be faced with a number of restrictions to weave your way through if you intend on renting out the mother-in-law apartment.

Living with the company: Long-term resident, relative or a renter, you will have to adjust to the new company if you plan on using your mother-in-law apartment as more than a storage space. Once the room exists, people will show up to fill it up - friends may feel free to drop in for a couple days or ask to stay in when they’re in town for unrelated work. Be prepared for this and have a plan in place for when and how the apartment will be used.

Adding a Mother-In-Law Apartment

The first thing to do when considering adding a mother-in-law suite is finding out whether it is legal. In addition to zoning ordinances and permissions, your city may have a maximum size of permitted mother-in-law apartments. For example, the city of Portland caps it at 800 square feet. Once all of that is done, look at your home and how you can add a structure like this with minimal structural adjustments. Converting a space costs less than constructing a new, detached structure altogether.

More importantly, think of how you plan on using it. If you want to rent it out, ensure it is built such that there is an independent exit that doesn’t interfere with your main house. If it is being built to house someone elderly, accessibility has to be your top priority. Avoid things like staircases and include the space for wheelchair ramps where necessary.

Be prepared to shell out the money as well: converting a space like a garage or basement can cost anywhere from $10,000 to $40,000. Constructing a new apartment can even hit  $100,000.

Buying a House with a Mother-In-Law Apartment

If you’re a buyer looking to purchase a house with a mother-in-law apartment, the most important thing for you to ensure is that it is, in fact, legal. An easy way to do this is going to the county office to see if it is listed there. Don’t just rely on the word of your agent or the sellers for this one as you have the responsibility of making sure your money is being invested into something that is worth it. This also helps avoid a lot of nasty surprises if you’re looking to rent it out at a later point. If you’re moving into a house with a mother-in-law apartment, or moving into a mother-in-law apartment yourself, you need the right kind of movers to get the job done. Luckily for you, 9Kilo Moving has a comprehensive network of movers who can help you out.