Oftentimes, living with an aging parent or a University returned kid, can cause minor inconvenience, both for them and you. You might want your children to live with you but don’t want them disturbing the household when they come home after a late-night party. Similarly, you might want to care for your aging parents without your privacy being disrupted. In such cases, a mother-in-law apartment comes to the rescue.

This accessory dwelling unit lets couples live with their in-laws and still maintain the distance required for a healthy familial relationship. The size of a mother-in-law suite or a granny suite can vary from one construction to another. Several factors like a state’s legal policies or your city regulations also play a role in determining whether you can have this convenient dwelling unit built in your property.

So what is a mother-in-law apartment? Is it meant to house only your in-laws or can it have different purposes? Whether you are buying a property with this attached dwelling unit or selling one, you could as well be planning to add this dwelling unit to your current property.

In all cases, read on to know more about this concept.

Understanding A Mother-in-Law Apartment

A mother-in-law apartment can be a fully self-sufficient house in itself provided its floor plan allows so. Some of these suits come with a minimum of bedroom and bathroom, while some are complete living spaces replete with living rooms and kitchens. You can add walls and install compartments, but only proper plumbing connections, gas piping, and electric supply can turn a mother-in-law apartment into a self-sufficient unit. The uniqueness of this unit lies in its convenience, with a separate entrance, the space becomes an individual dwelling that is standalone from the main house. It can either be in the same house or can be a separate unit like a cottage on the same property. A garage, basement, or an outdoor yard lying unused can be converted into a mother-in-law apartment with the right design, resources, and funds.

Mother-in-Law Apartment: Basic Function

The basic goal of a mother-in-law apartment is letting two or more generations of a family live together in harmony while respecting each other’s space and privacy. This separate unit incorporated into the main house can come with the house if its earlier residents had it constructed. Or it can be built once the need for it starts arising. It can act as a separate space for your guests or parents, and you can still stay closer to them without causing any hindrances. Though constructing it might burn a hole in your pockets, several benefits will compensate for the expenses.

It’s very common for families to renovate unutilized spaces to make more independent living spaces for grown-up children or aging parents. Don’t do it just because there is extra space in your property, as building this unit without a proper plan can often backfire. But this shouldn’t put you off, there are several advantages to it too. Be it converting that unused basement into a mother-in-law apartment or moving into a property with an existing mother-in-law apartment, you must know how to make full use of it.

Benefits Of A Mother-in-Law Apartment?

With the rise of families opting to live under one roof, this is an ideal option. According to a Pew Research Center analysis, 20% of Americans, or 64 million, lived in multi generational households. So that is the reason why home builders these days are offering specific floor plans to fit this need. And guess what? Buyers are ready to shell out more to move into such properties because a mother-in-law isn’t the only one benefiting from this setup!

For Grown-up Children

As more and more 20-something adults are opting to live with their parents to save on expenses, a mother-in-law apartment fits the bill. Analysis of monthly Census Bureau data for July 2020 showed that 52% of adults resided with their parents in light of the Pandemic. While this brings families closer, a mother-in-law apartment gives much-needed independence to both parents and children.

Also, this will work in your favor after the pandemic too, with a mother-in-law suite, your children can lead a separate existence, come late from work, bring home friends or play loud music without ruining your peace. Since their Additional Dwelling Unit (ADU) will have a separate entrance and living area, you can lead an uninterrupted life in the main house, though we cannot guarantee the loud music part!

When Guests Come Over

If your relatives are visiting from across the state, won’t it be cold to put them up in a hotel? Having a mother-in-law suite can act as a solution, you can have them stay at your place and still keep them at an arm’s distance. This way, you can be a good host without causing inconvenience to anybody. Are you hosting a party and your friends need a place to crash for the night? Show them to the mother-in-law suite, this can assure no one is awkward and no one is turned away late in the night!

This ADU acts as the perfect suite for your guests, so you can have them stay close without compromising your privacy.

For Live-in Nannies

A mother-in-law suite can act as a self-contained apartment for your Live-in nanny. You can accommodate her so she can be just a call away and still maintain her independence. This way, you don’t have to pay for her additional expenses since the maintenance for your entire property will be combined. It also gives you an upper hand while employing as it adds as an additional factor for someone choosing a nanny position.

For The Elderly

Coming to the main purpose of this suite, housing your aging parents under the same roof with you reduces the expenses you might otherwise incur for a nursing home. This also acts in favor of your parents, having their children around as caregivers give them a sense of warmth and belonging. Often, aging parents living away from their family feel lonely and depressed, having them move into your home allows them the comfort of staying with you. But they can interfere in your household affairs, which can strain relations, having a mother-in-law suite acts as the perfect solution to this.

Your children too can flourish in a warm environment under the care of their grandparents, so they don’t have to grow up around babysitters while you are away. When the younger children are too much for the grandparents to handle, they can retire to their separate quarters and find their peace. Having a mother-in-law apartment can let the whole family make memories together, from shared dinners and movie nights to gardening. All while still maintaining the space between all members.

For Extra Income

When there is no one shifting into your mother-in-law suite anytime soon, you can rent it out. Having a tenant move in can have a huge financial advantage. For first-time home buyers, the mortgage payments can be taxing, with endless bills to pay and expenses to incur. The rent money can help with bills and payments. The rental income can also go towards saving up for a down payment for your next home. Having this additional income can help save up for house renovations, family vacations, and other daily expenses. Not to mention the money you end up saving for your retirement years!

And when you decide to sell your house, having a mother-in-law suite can increase your resale value. An additional living space apart from your main house will get you a higher listing price as most homebuyers prefer buying a house with a readily constructed in-law suite.

Additional Storage Space

Having more appliances and furniture in the house can cause inconvenience, which can push you to the point of using eBay and LetGo to sell off your extra household items. A mother-in-law suite can create additional storage space in the house and you don’t end up throwing away things that are in working condition. All your extra furniture, large sports gear, and seasonal items can find a place in this suite.

Benefits Of an Unused Mother-in-Law Suite

List It On AirBnb: If you reside in a tourist destination, a mother-in-law suite can be a perfect Airbnb investment property. It can earn you more profits in a low-risk way as a property owner. You can make it available on Airbnb only when you want to, this flexibility allows you to put up guests, relatives, or friends when they visit you. This earns you income without committing to long-term tenants.

Work From Home: An empty mother-in-law suite acts as an added advantage to anyone working from home. Having these separate working quarters can give you the much-needed privacy to focus on your work. The disturbances of working from home with kids and pets around will all be eliminated when you shift your work desk to an in-law suite.

Turn It Into A Fitness Area: Did the previous homeowners leave you with an in-law suite, but you have no one moving into it? Turn it into a fitness area. Having an attached fitness space can help you workout better while still being close to your home. All your gym equipment can find a place, plus you will slip into a routine when you have a separate fitness space.

Make An Art Studio Out Of It: This can be an excellent way to save costs of getting your own art studio. Having a video editing or music studio can require a good speed internet, the expenses of cable and wifi can be split between your home and studio if you decide to turn your in-law suite into a studio. You will also have the benefit of having visitors over to your art studio since it will have a separate entrance from your main house. Not to mention being a few walls away from the primary living space, you can grab a quick bite while you immerse yourself in your work. Anytime you don’t feel creative, you can take a break and retire to your bedroom, a benefit you cannot have when working from a studio away from home.

Drawbacks of A Mother-in-Law Apartment

While an Additional Dwelling unit sounds like an answer to all your problems, you must not overlook these features before investing your time and money.

It Can Burn A Hole In Your Pockets

Though this ADU is attached to the main house, it can cost you the same as running two households, with increased bills for water, electricity, and energy costs. If you are building a mother-in-law suite in your existing space, it can cause great expenses, because the setup doesn’t end at renovating the place and building new walls. You have to pay attention to minute details like plumbing and electricity.

This extra suite can be a costly venture, with expenses rising with each addition you make to it. The added utility costs like heating and cooling, repair work, and maintenance can be a setback. If your current homeowner’s insurance policy does not cover the ADU, you will have to incur added costs to insure the in-law suite. Not to mention the costs you will incur to make it accessible to the elderly.

Also Read: Average Cost of Utility Setup

City Zoning Regulations

Most US residential areas were governed with strict building codes after World War II to set limits on the size and separation of single-family properties owing to the rise in population density. But recently, zoning changes in several areas around the country have worked in favor of those planning to build accessory dwelling units. The zoning laws limit the size and construction style of new units and specify that the owner must reside on the property.

When you construct a mother-in-law apartment, it’s important to keep a check on your city’s building regulations. Your local building codes also specify which features you can add to your ADU, like adding a kitchen can require separate permits. For this, remember to choose the right home additions contractor, as they will take care of getting proper permits.

Upkeep And Maintenance Of A Mother-in-Law Apartment

Though you would love to, you cannot build a mother-in-law apartment and forget about its upkeep. It demands constant maintenance checks just like your primary house would, and this gets more demanding when you have tenants over. That’s because the repair works of your main house can wait, but that of tenant quarters cannot. You also cannot avoid the weekly cleaning of the toilets, mopping the floors, dusting, replacing light bulbs, and attending to appliances. If you have guests moving in, you have additional cleaning to look after. Not to forget the efforts you will put in once they leave the suite! Though getting a mother-in-law apartment looks like a convenient option, there is a lot of upkeep that goes into it, which can be time-consuming and costly.

Building The Suite In Your Existing Home

The moment you start thinking about getting a separate dwelling unit, Pinterest is going to flood you with ideas. Though you will wish that you could skip directly to the creative decor part of it, that will not be the case in reality, since there will be a lot of building codes to check and permits to apply for before you start the construction process.

Finding The Right Spot For A Mother-in-Law Apartment

Figuring out the perfect spot to convert into a suite is the first step in this process. Your house might have several options, like the basement, attic, or yard, but you must consider all aspects before you start laying the bricks. The most suggested spot is usually an underused room on the first floor, preferably near a bathroom. The most cost-effective way is to build the suite in the basement, but you must consider your parent’s abilities before finalizing this, having a walkout level garage or basement turned into a mother-in-law apartment can eliminate the problems with taking the stairs. Choose a spot where you can easily provide bathing and kitchen facilities without disrupting the original design of your primary living space.

Making Your Mother-in-Law Apartment Accessible

While building a mother-in-law apartment, you must consider long-term needs. Your parents can be healthy, but it is always better to include wheelchair accessibility or grab bars for the bath. It ensures their new home is designed to suit their needs as they grow old, this also makes them feel loved since you put so much thought into the design, giving an unspoken message that you want them to live with you for longer. Making it accessible includes attention to details like installing pull-out drawers, adjustable sinks, shower seats, anti-skid bathroom floors, using lever-style handles on all room doors. If you are planning to host your parents, remember to not build an in-law suite in the upstairs attic as it can be a huge concern with all the climbing.

Paying attention to accessibility also acts as an added advantage as it increases the resale value of your property.

Also See: Top Mobile Home Movers in the US

Finding The Right Contractor

Half the battle is won when you find a contractor who has worked on building in-law suites before, getting a certified aging-in-place specialist is an added boon. They know your local building codes and zoning laws better and can guide you along the process and even get you the required permits as we mentioned earlier. An experienced contractor will help you with design ideas and suggest the best ways to make your in-law suite as functional as possible.

Additional Details To Note

Small things like a separate laundry space, entrance door, and appliances can make a huge difference. This makes your parents or children living in the suite feel a sense of self-esteem and independence. Add features like lights outside the door, handrails along the stairs, and potted plants to make the place feel warm and welcoming. A separate kitchen space can also go a long way in making the resident feel independent. Even if they have dinners with you, a separate kitchen can allow them basic amenities without disturbing your household schedules.

Another aspect to consider is sound insulation, adding sound dampening insulation on interior walls can provide peace to your parents or in-laws. Going one step further and adding dustproof and easy to clean material for the suite will act as a plus point, as it allows elderly parents to sit back and relax without worrying about constant cleaning. This also acts as a benefit if your adult children are moving in, as they won’t have the time to clean and dust their living quarters.

See Also: Moving with Kids – A Detailed Step-by-Step Guide | Things You need to Buy for your First Apartment

How Much Does A Mother-In-Law Apartment Cost?

According to Realtor.com, a mother-in-law suite can cost you anywhere between $40,000 to $125,000. If you want to remodel your in-law suite, the cost can range from $5,000 to $100,000. The cost can vary depending on various factors like the size of the in-law suite, the area of residence, the cost of raw materials, your zip code, local labor costs, and the scope of your project.

It also depends on where you plan to build the suite, like converting a garage is cheaper than converting an attic for the mother-in-law apartment. We suggest deciding on a budget beforehand and then designing the suite as you don’t want to run into unwelcome expenses during the process. Hiring a remodeling expert can save up a lot of money as you can have a clear picture before you start work.

Check out the below table to get an idea of the approximate costs according to city and project size.

CitySize of ProjectAverage Estimated Cost (USD)
Birmingham, Alabama Small
Des Moines, Iowa Small
San Francisco, CaliforniaSmall

Though it is expensive to build a mother-in-law suite, it is a much better alternative to nursing homes. Genworth’s Cost of Care Survey reveals that in the United States, the average cost of a private room in a nursing home is around $105,000 annually. Having a suite saves you a great deal of expense in the long run.

Moving Into A Property with an Mother-In-Law Suite

When you have finally found the right home with a cozy little mother-in-law suite, it’s time to move into it. But not before you have checked all specifications. Is the in-law suite insured? Is it legal and officially listed? These are questions you should look at alongside finding out whether it ticks all the checkboxes you had in your mind. Once everything is in place and finalized, prepare for the big move! Go through our blogs, we have varied recommendations for each moving concern to help make your move easier.


Can you rent out an inlaw apartment?

Yes, you certainly can. Renting an inlaw apartment is a great way to make some money. But know that you would have to adhere to the local municipal laws when it comes to renting out property. After all, the inlaw apartment would still be your own property and part of your space.

How big is a mother in law house?

The size of a mother in law suite can be anywhere from 350 sq ft to 1000 sq ft. Essentially, it can be as large as a 2 bedroom home, depending on the space available on your property land to build it, among certain other factors.

Also Read: Best Apartment Moving Companies in the America