Mother-in-Law Suites Are Having A Moment in 2025

If you have an aging parent (or other family member) moving in, you might be feeling a mix of love, duty, and stress. You want your loved one close by where you can help care for them – but you also worry about everyone’s privacy and daily routines. 

Will you all feel cramped? How will Mom or Dad maintain a sense of independence? Is your home safe and accessible enough for them as they age? These are valid concerns many families face. In fact, nearly 1 in 10 U.S. households are now multigenerational, and that number is growing as people live longer and housing costs rise.

Without a plan, it’s easy to feel overwhelmed. You might fear that your parent won’t be comfortable in your home’s current layout, or that costly mistakes in remodeling could add stress during an already anxious time. 

The good news: there is a solution that addresses these worries head-on. A well-designed mother-in-law suite can provide a safe, private home for your loved one right under your roof (or in your backyard) – so you can care for them without everyone feeling like they’re on top of each other.

What Is a Mother-in-Law Suite?

While the name may bring to mind images of an aging parent living just down the hall, a mother-in-law suite can serve a wide array of needs. It’s essentially a small, standalone dwelling with its own entrance, bedroom, and bathroom, as well as a living area and kitchen or kitchenette. 

Legally, a mother-in-law suite is known as an accessory dwelling unit (ADU) — a secondary housing unit located on the same property as an existing single-family home. Due to the legal implications of this arrangement, they’re typically subject to local zoning regulations and permitting requirements. 

Many cities are now updating their codes to allow for these types of structures. Not only are they great for homeowners who may need to house a long-term guest or family member, they can also be rented out, effectively increasing the city’s housing supply. 

As mother-in-law suites become more common, they’re taking on a variety of forms to suit different needs, budgets, and property layouts.

Types of Mother-in-Law Suites

Mother-in-law suites can be situated within the main house, or exist as a separate structure elsewhere on the property. If you’re considering building an in-law suite, you may already have a specific area in mind, but it’s worth exploring your options to fully understand the benefits and drawbacks of each.

Attached (Interior, Garage Conversion)

Attached or interior mother-in-law suites are built within the home’s main structure. This could be a converted basement, attic, attached garage, or sectioned-off area with a private entrance. 

Because these suites exist within the main house, they’re a great option for when you may want to house a family member who requires privacy and independence, such as an aging parent or young adult.

Detached (Guest Houses)

A detached mother-in-law suite exists as a separate structure on a residential property. As a standalone building, this type of in-law suite offers maximum privacy, making it ideal for those who might want to rent it out for extra income. 

While a detached in-law suite may cost more to build, it can add significant value to the property and allows for greater design flexibility.

Why Add a Mother-in-Law Suite – Benefits for Your Family

Building a mother-in-law suite is an investment in your family’s comfort and well-being. Here are some of the major benefits that Central Ohio homeowners gain from these additions:

Caring for Aging Parents at Home

The number one reason for an in-law suite is to bring an elderly parent or in-law closer. Instead of worrying about them living alone or in a far-away facility, they can live right beside you. 

This proximity provides immense peace of mind – you’ll know they’re safe, and you can assist quickly if needed. At the same time, they maintain a sense of independence by having their own kitchen, bathroom, and living area.

Maintaining Independence & Privacy

Both generations benefit from some breathing room. Your parent gets a private, dignified space to call their own (no one wants to feel like a permanent “guest” in their child’s house). And you and your kids maintain normal routines without tiptoeing around a live-in relative!

Multi-Generational Living & Support

With multiple generations under one roof, families often experience closer relationships and mutual support. Grandparents can be more involved in daily life – from sharing family dinners to helping with childcare. 

Meanwhile, adult children (you) can more easily assist your parents with transportation, chores, or health needs. This strengthens family bonds and reduces social isolation for seniors who might otherwise be living alone.

Cost Savings & Practicality

Combining households can be more economical than maintaining separate homes or paying for assisted living. Living together often means sharing utilities and resources, and it can eliminate or reduce the cost of outside care or housing.

Additionally, having parents close by can save you travel time and stress. The convenience of not having to drive across town frequently is a huge relief for many working families.

Increase in Home Value

Adding a quality in-law suite can boost your property’s value and appeal. Homes with a legal accessory dwelling (complete with kitchen and bath) often command higher prices on resale – one study found homes with ADUs were priced 30-35% higher on average than those without. 

Even if ROI (return on investment) isn’t your primary goal, it’s nice to know that creating a multigenerational-friendly home can make your property more attractive on the market. At the very least, extra square footage and an additional self-sufficient living area are features many buyers appreciate.

Common Features of a Mother-in-Law Suite

Generally speaking, a mother-in-law suite should have all the essential features of any other residence, albeit on a smaller scale. That typically includes a private entrance, living area, kitchen (or kitchenette), bedroom, and full bathroom. 

Depending on the size of your suite, you may opt for a studio layout where the bedroom, living area, and kitchen are combined into a single open space.

If the suite is being built as a legal accessory dwelling unit (ADU), many locales require certain features in order for it to qualify. Typically, these include:

• A separate entrance
• Full kitchen facilities (a kitchenette may not be enough)
• A full bathroom
• Permanent utility connections (water, electricity, sometimes gas)

Mother-in-Law Suite Building Requirements

If you’re building a mother-in-law suite — especially one intended to qualify as an ADU — you’ll need to follow your local building and zoning regulations. These requirements vary by city and state, so be sure to check with your local planning department. Below are some of the most common requirements.

Local Zoning Laws

Every city and township has zoning rules that dictate whether a secondary living unit (ADU) is allowed. The good news is that Columbus and many Central Ohio communities do recognize mother-in-law suites (ADUs) as a viable housing option. 

However, specifics can vary. Zoning codes may impose rules on lot size, setbacks, and size limits for an in-law suite. For example, there might be a maximum square footage or a requirement that the ADU is smaller than the main house. Some neighborhoods (or HOAs) might restrict detached units or require that an in-law suite cannot be rented out to non-family members – it’s crucial to know these details upfront. 

RSDB will research and confirm what’s allowed in your area. We’ll check the zoning designation of your property and see if an attached or detached addition is permissible, taking into account any historic district or HOA guidelines if applicable.

Building Permits and Codes

Just like any substantial remodeling or addition, an in-law suite project will require building permits and inspections. This process ensures the construction is safe and up to code (for structural integrity, electrical, plumbing, egress windows, fire safety, etc.)

It might sound daunting, but we’ve got you covered. Our team will create the necessary architectural plans and documentation, and we’ll handle the permit applications on your behalf. We are very familiar with Central Ohio building departments and codes, and we design every project to meet or exceed those standards. 

During construction, inspections will be scheduled to approve things like the foundation, framing, wiring, and so on – RSDB coordinates these and addresses any issues, so you don’t have to sweat it. We make sure there are no legal or safety surprises when your suite is finished.

Utilities and Infrastructure

An in-law suite will need essential utilities – electricity, heating/cooling, plumbing for kitchen and bath, etc. Part of our planning is determining the best way to extend or modify your home’s systems to serve the new space. In many cases, the suite can tie into the existing HVAC and plumbing systems (perhaps with some upgrades or additional water heaters/HVAC zones to handle the extra load). 

In other cases, especially for a detached unit, it might make sense to have separate systems. We’ll also consider things like electrical capacity (does your home’s panel need an upgrade to support a full kitchen in the suite?), septic or sewer connections, and proper insulation and ventilation. Rest assured, our experts will engineer the solution that works best and meets code. No detail is overlooked – from ensuring proper drainage around a new foundation to planning for internet/cable access in the suite.

How to Build a Thoughtfully Designed Mother-in-Law Suite

We understand that welcoming an aging parent into your home is both a heartfelt decision and a significant undertaking. Our proven 4-step design-build process is crafted to ensure that this transition is seamless, respectful, and tailored to your family’s unique needs.

Step #1 – Listening to Your Story

Every successful project begins with understanding. We start by scheduling an on-site consultation to listen to your vision, concerns, and the specific needs of your family. Whether it’s creating a private space for your parent or integrating universal design features for accessibility, we aim to grasp the full picture.

During this phase, we also discuss budget considerations and outline a design service retainer proposal. Once agreed upon, we embark on the journey together.

Step #2 – Research, Design & Presentation

With a clear understanding of your goals, our team conducts thorough research and begins the design process. We take precise measurements and develop multiple design concepts, presenting them through detailed CAD drawings and renderings.

You’ll have the opportunity to explore material selections, visit local showrooms, and make informed choices that align with your aesthetic and functional preferences. Together, we refine the scope of work and finalize the budget, ensuring transparency and alignment every step of the way.

Step #3 – Bringing the Design to Life

Our commitment to communication sets us apart. Through our cloud-based application, Job Tread, you have real-time access to project updates, schedules, and documentation. Approximately 1-2 weeks before construction begins, our project manager will meet with you on-site to establish a clear timeline and address any final questions.

As construction commences, we manage every detail with precision and care, ensuring that the new addition integrates seamlessly with your existing home and meets the highest standards of quality.

Step #4 – The Reveal

Completion day is more than just the end of a project; it’s the beginning of a new chapter for your family. We conduct a thorough walkthrough, address any final touches, and celebrate the transformation of your home.

Our “Happiness Guarantee” means we’re committed to your satisfaction not just today, but for years to come. Should you need any adjustments or support in the future, we’re here for you.

Cost of Building a Mother-in-Law Suite

The cost of building a mother-in-law suite can vary widely depending on size, location, materials, and whether it’s attached or detached. While national averages range from $50,000 to $150,000 or more, the best way to get an accurate estimate is to consult a licensed contractor.

Mother-in-Law Suites: Frequently Asked Questions

Are Mother-in-Law Suites Legal?

Mother-in-law suites — especially those used as accessory dwelling units (ADUs) — are legal in many areas, but not everywhere. It’s crucial to check your local laws before starting a project.

Does a Mother-in-Law Suite add Value?

Yes, a well-designed in-law suite can increase your home’s resale value and appeal to a wider range of buyers, especially those looking for multigenerational living or rental income potential. However, actual value added depends on local market trends and build quality.

Work with Ron Scott Design Build to Create Your Perfect Mother-in-Law Suite

Are you a Central Ohio resident looking to get ahead of the curve on building an ADU? Whether you’re planning for family, guests, or rental income, Ron Scott Design Build can help you. We’ll bring to life a custom mother-in-law suite that fits your home and lifestyle. We specialize in high-performing home builds and remodels.  Contact us today to schedule a consultation!