What Is an In-Law Suite?

Small house living space in-law suite

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More and more, multigenerational homes are becoming the norm. Whether it’s parents living with children, grandparents living with grandchildren, or all of them living together at once, some extra space is needed to accommodate everyone comfortably. In these situations, in-law suites are a fantastic option. 

As suggested by the name, in-law suites are often used for aging parents to allow them the privacy and ability to live on their own while still being close by when they need a helping hand. At the other end of the spectrum, an in-law suite may also serve as a transition for young adults. Rather than leaving home, living in an in-law suite affords them a measure of independence while enjoying the security and comfort of having family in close proximity.  

Though this is the first thing that comes to mind when talking about in-law suites, this is not its only purpose. In-law suites are gaining in popularity as a way to boost rental income, either through short-term vacation rental or as an apartment. For personal use, an in-law suite is sometimes built to accommodate a home-based business while still providing a sense of separation. It can also make an attractive option as a guest house for families that frequently host out-of-town company. In these cases, the characteristics and features of the in-law suite will vary widely based on the purpose and design choices that the homeowner has in mind. 

What exactly is an in-law suite? Here we will break down what characterizes an in-law suite, the pros and cons of having one, and the approximate cost of building one. 

Key Characteristics of an In-Law Suite

Also known as a granny pod, ohana unit, or mother-in-law suite, an in-law suite is a separate living space usually consisting of a bedroom, bathroom, living room, and small kitchen. It can be connected to the main home, such as in the case of an addition, renovated garage, or basement, or it may be a separate structure on the same property. In either case, a key feature of an in-law suite is a separate entrance in order to maximize privacy and accessibility.  

Other key characteristics of an in-law suite are harder to pin down. The form and function of the space will vary considerably based on its intended purpose. An in-law suite built with aging parents in mind will have features designed for comfort and ease of use, such as limited or no stairs, a shower seat, or railings. 

In-law suites that are built with temporary guests in mind, like a vacation rental or guest house, will likely have features that make the small space functional but fun. Depending on the size and configuration of the space, you may find that an in-law suite overlaps with tiny house design and living ideas.  

What to Know Before Building an In-Law Suite

In-law suites are an attractive option for their versatility and convenience. But before you pick up your tools and start drawing up plans, there are a couple of important things you need to do. The first is to check your local ordinances. A trip to the zoning office with your lot and block number will allow you to learn all the local laws that apply to your property and if an in-law suite is permitted.

If permitted, take note of what you can and cannot include in an in-law suite. If an in-law suite is not permitted, you can still move forward by obtaining a variance. This could cost up to $500 and will require sending letters to your neighbors to collect their signatures.

After checking what is permitted on your property, always make sure to obtain the proper building permits.  

Pros and Cons of Building an In-Law Suite

Such a large project has its pros and cons. Here we will break them down so you can take in all the factors before deciding whether an in-law suite is your best option. 

Pros
  • Offers privacy and close proximity to the main residence

  • Increase in the resale value of your home

  • Potential income as a short or long-term rental

Cons
  • Major additions can become costly 

  • Local ordinances may govern building specifications

  • Expect increased utility costs associated with the in-law suite

Typical In-Law Suite Costs

As mentioned, an in-law suite is a large project and therefore will incur considerable costs. Renovating an existing space, such as a walk-out basement, a large room, a garage, or an attic, will make the project more cost-effective. If an addition needs to be built onto your home or a separate structure needs to be constructed, the cost will be much more. 

Since each situation differs greatly, costs vary widely. Generally, an in-law suite will cost anywhere from $40,000 to $125,000 depending on the complexity of the project.

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  1. What Is an In-Law Suite? A Smart Feature—Even If Mom Isn’t Moving In. National Association of Realtors.

  2. How Much Does an In-Law Suite Cost? Home Advisor.