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Mother-in-law suites, explained

Published June 3, 2024| minute read

    Despite what the name suggests, a mother-in-law suite isn’t a designated space for a spouse’s mom. “Mother-in-law suite" is another way to describe an attached or detached living space that’s on the same lot as the primary residence. While the name reflects the purpose of providing housing to family, they’re not limited to just that. Though mother-in-law suites may be helpful if you’re seeking to provide housing for loved ones, they may also serve as a source of rental income. To better understand if this type of accessory dwelling unit and how it may work for you, let’s look at the types of mother-in-law suites you may encounter and key considerations for anyone exploring this option.

    What is a mother-in-law suite?

    A mother-in-law suite, also known as a granny flat, an in-law suite or accessory dwelling unit (ADU), is a living space attached to or located on the same property as a primary residence. A house with a mother-in-law suite is often intended to provide convenient and private housing to family members as they age. Outside of this more traditional purpose, however, the space may sometimes provide housing for younger family members as they save for their own place, or to help the homeowner generate passive rental income. As mother-in-law suites come in several different forms, both attached and detached, let’s explore the various options and their unique qualities.

    Types of mother-in-law suites

    While all mother-in-law suites function as a separate living space for their occupants, these dwellings can take several different forms depending on the primary residence, local zoning laws and the lot’s available space. If you’re looking for mother-in-law suite ideas, these common types may be worth looking into:

    • Attached mother-in-law suite: An attached mother-in-law suite is part of the primary residence but designed to be a separate living space. This generally means it has its own entrance, bathroom, sleeping area and kitchen or kitchenette.
    • Detached suite: A detached mother-in-law suite is a separate structure on the same property as the primary residence. These detached units may be standalone cottages, guest houses or apartments and offer more privacy to its occupants than an attached suite.
    • Garage conversion suite: This type of mother-in-law suite involves transforming a space that’s generally used to store cars into a livable space. Garage conversion suites may be attached or detached, depending on the garage’s location in relation to the primary residence.
    • Basement conversion suite: Similar to a garage conversion, a basement mother-in-law suite modifies a pre-existing area of the home to create a separate living space. Basement suites are, by nature, attached to the primary residence, but may feature a separate entrance.

    Building a mother-in-law suite

    Building a mother-in-law suite can potentially be a rewarding process, especially when you’re creating a living space for a loved one. Whether you’re helping a family member or looking for a way to generate rental income, there are some considerations to keep in mind while taking on this type of project, even if some of these dwelling units are easier to construct than others.

    Considerations for building a mother-in-law suite

    • Zoning and permits: Research local zoning laws before embarking on your mother-in-law suite journey. As every locality has different rules regarding setbacks, lot size, accessory dwelling units and parking, it’s generally a good idea to clarify before putting in time, effort and money into a project.
    • Utilities and infrastructure: Mother-in-law suites often use the same utilities as the primary residence, so it may be helpful to ensure the existing gas and water lines or electric can handle the additional living space.
    • Accessibility: If you’re building a suite for an aging or disabled family member, it may be a good idea to go with a first-floor unit or invest in features that allow people with mobility issues to get around easily.
    • Financing: While building a mother-in-law suite is less of an undertaking than some other living spaces, it may still be a significant financial investment. Exploring your budget and financing options ahead of the project may help you avoid potential surprises and holdups due to lack of funds.
    • Return on investment: Whether you’re building a mother-in-law suite for family members or to create a rental opportunity, it may be helpful to determine the return on investment (ROI). As some mother-in-law suites involve a good deal of work, you’ll likely want to see that work and money pay off in the long run. If helping loved ones is the priority, this may not be as much of a factor, depending on your financial status.
    • Insurance: Any type of ADU has the potential to affect your homeowners insurance. As such, it may be a good idea to reach out to your provider to understand if you’ll need to purchase additional coverage or if the impact on your existing policy will be worth it.
    • Privacy: Privacy is generally appreciated, whether you’re dealing with family or tenants. Familiarity may breed annoyance more often than contempt, but a little privacy can go a long way toward keeping people happy. Look into separate entrances whenever possible and consider strategic privacy-minded landscaping.

    In summary

    Adding a mother-in-law suite to your home has its potential perks, from helping aging family members or other loved ones to generating rental income and possibly adding value to a property. Despite these possible benefits, any construction, renovation or conversion is an undertaking with unique considerations. Doing your due diligence may help make the experience a smoother one or help you avoid a project with limited returns.

    Mother-in-law suite FAQs

    1. Does a mother-in-law suite add value?

    A mother-in-law suite may add value to a property, but this depends on many factors such as its location, size, the quality of construction as well as zoning or regulations. Additionally, some homebuyers may not want or need a mother-in-law suite on the property. Because of these considerations, it may help to contact a local real estate professional for a tailored assessment of your situation.

    2. How much does a mother-in-law suite cost?

    The cost of a mother-in-law suite varies depending on the type of unit, whether it’s a new construction or conversion, as well as the quality of materials, the professionals hired and local permit fees. Consulting with a real estate professional may help you demystify potential costs.

    3. What is the difference between a guest house and a mother in-law unit?

    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.

    4. How to finance a mother-in-law suite?

    If you’re looking to finance a mother-in-law suite, there are several options you can explore, such as home equity loans, cash-out refinancing, construction loans or manufacturer financing. Be aware that Chase may not offer all these options.

    Take the first step and get preapproved.

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