Mother In Law Suite: 8 Key Things To Consider Before Adding a New Space

Are you considering adding a mother in law suite to the floor plan of your single-family home? Or, are you in the process of buying a home with a mother-in-law apartment to make some rental income?

Congratulations! You’re in the right spot to determine if adding a mother in law is a worthwhile investment.

What is a Mother In Law Suite?

A mother-in-law suite is a dwelling that is separate from the main house. It can be attached or detached, and it usually has a separate entrance. 

It will have things that a traditional apartment does, like a bedroom, bathroom, living space, and a full kitchen. 

Additionally, a mother-in-law suite is an excellent option for those that want to have a rental property or an additional space for guests or family members to stay in.

Types of Mother in Law Suites

Converted Space

Many homeowners convert an existing space into a mother-in-law suite, including an unused garage or a basement. 

Because the space is already attached, the homeowner can usually convert it into a mother-in-law suite without investing a lot of time or money. 

If it is just one open space, such as a finished basement, they may need to put up walls and install plumbing for a bathroom before guests can occupy it.

Accessory Dwelling Unit

An accessory dwelling unit (ADU) is entirely separate from the main property. For a homeowner to build an accessory dwelling unit, the property needs to have sufficient space. 

An ADU can be more expensive than converting a space into a livable area. As a result, many homeowners choose to have an accessory dwelling unit if they don’t have any extra space in their existing home to convert into a mother-in-law suite.

8 Things To Consider Before Adding a Mother In Law Suite?

1. Zoning Laws

Before building a new structure, you need to determine your local zoning laws and whether you plan to convert or create a unit. You also need to check with your local ordinances and obtain permits before any construction occurs. 

Many communities are stringent on what’s allowed and what isn’t for mother-in-law suites. Therefore, it’s better to learn about the zoning regulations beforehand to avoid fines or remove the structure.

2. Building Codes

Because someone inhabits the mother-in-law suite, it needs to be up to current building codes, which will ensure the safety of the tenant and the surrounding property. The building codes may be similar to those of the main property. 

3. Location

If you are interested in adding a mother-in-law suite to your property, you need to consider its location within the property. This space will be a permanent structure, and you need to think carefully about where the best place to put it is so that the tenants don’t disrupt your daily life.

4. Homeowner Association

Not all homeowners associations (HOA) allow mother-in-law suites, which is why you need to read your community bylaws beforehand to determine whether or not you are allowed to perform this kind of home improvement to your property. Even if the tenant lives in a converted space that’s already a part of your property, your HOA still may forbid it. 

In addition, some homeowners associations may require you to attend a board meeting and submit plans before they approve of the structure.

5. Cost to Build

Building a mother-in-law suite often does come with a lot of expenses. In addition to building materials, you will need to pay for things like surveying and permits. 

To determine the exact cost to build a mother-in-law suite, a contractor with some Bob Vila skills will need to review the space and talk to you about what features you want it to have. 

6. Utilities

No matter where a homeowner locates the mother-in-law suite, the homeowner still needs to consider the utilities. The tenant needs to have access to water and electricity at all times. This requirement may mean that the homeowner needs to run plumbing, sewer, and electrical lines into the space.

7. Loss of Yard Space

Those who end up having an accessory dwelling unit built will have to deal with a loss of yard space. An ADU tends to take up a lot of space that the homeowner can’t get back unless they tear the structure down. However, if the homeowner has a large yard or barely uses it, they probably won’t mind the loss of yard space. 

8. Insurance

While it is possible to ensure a mother-in-law suite, it can be expensive if a homeowner rents it out because homeowners must obtain landlord insurance. The homeowner must get adequate coverage as this will financially protect them if something catastrophic happens to the property. 

How Much Does it Cost to Add a Mother In Law Suite?

The cost to build a mother-in-law suite will vary with the type of structure. Converted suites are generally the cheapest and may only cost a few thousand to build if there’s already electricity and plumbing in the structure. 

It’s not uncommon for accessory dwelling units (ADUs) to cost $50,000 to $100,000 to build. Many of the costs have to do with the materials used and how much construction has to be done. 

Does Adding a Mother In Law Suite Add Value to Your Home?

One of the perks of adding a mother-in-law suite to a home is increasing your real estate value. How much value it will add will depend on several factors, such as its square footage and the location of the space. If there are no other mother-in-law suites close to the home, it may significantly increase the property’s value.

6 Uses of a Mother In Law Suite

1. In-Law Suite

Many homeowners add a mother-in-law suite to their home for their in-laws. An in-law apartment is relatively common for those who want to give their aging parents a safe place to live or family members who like to visit for an extended time throughout the year.

2. Guests

A mother-in-law suite is an excellent option for homeowners who need a guest house for their visitors. Their guests won’t have to worry about where to stay, allowing them to save money. 

3. Nanny

It’s pretty common for many families to have live-in nannies to take care of their children and manage their households. A mother-in-law suite may allow the nanny to have their own space when they aren’t watching the children, and the family will always have access to their nanny when needed.

4. Adult Children

Not all adults leave home once they graduate high school. However, if their parents want to give them a private living area within the property, they may consider adding a mother-in-law suite. 

It will allow older children to feel independent, and they will still be nearby when they want to spend time with their parents. In addition, a mother-in-law suite is a great option for young adults who are in college or saving to buy a house of their own.

5. Tenant

Those looking for a way to bring in an additional income may choose to rent out their mother in law suite. Because these dwellings tend to have everything that a typical apartment does (i.e., full bath, living room), the homeowner can usually rent them reasonably easily. 

Because the mother-in-law suite is on the same property, the homeowner will easily make repairs and collect rent each month.

6. Storage

When no one uses a mother-in-law suite for tenants, guests, or in-laws, homeowners can use it for storage. Many homeowners find that these suites are a great place to store holiday items, bulk food purchases, or clothing out-of-season.

Final Thoughts

There are multiple things a homeowner can do with extra space. Whether it’s a space for your in-laws or your out-of-town guest, it makes things a little easier. However, there are multiple things you need to consider before picking out design ideas.

First, check with your local ordinances to see if it’s allowed. Next, reach out to a trusted contractor to get an accurate estimate of how much the work will cost.

These first two questions will determine if it’s even possible or at least within your budget.