What Is an ADU? The Complete Guide to Accessory Dwelling Units
The “missing middle” of housing isn’t found in a high-rise apartment or a suburban subdivision; it’s actually right in your own backyard.
As families grow and the housing market evolves, more homeowners are asking: What is an ADU?
Beyond just a buzzword, an Accessory Dwelling Unit (ADU) represents a powerful shift in how we think about our properties.
It is a way to provide a haven for loved ones and build long-term wealth through smart home improvement.
At Lapp Structures, an ADU is more than just four walls and a roof; it’s an investment in your family’s future and a creative solution to modern living challenges.
What Is an ADU in Real Estate?
To put it simply, an Accessory Dwelling Unit (ADU) is a secondary housing unit located on the same lot as a primary, single-family home.
In the world of real estate, you may have heard them called “granny flats,” “in-law suites,” or “backyard cottages.”
While they are smaller than the main house, a true ADU is a complete, independent living space. To be classified as a legal dwelling, it must have its own:
- Entrance
- Kitchen area
- Bathroom
- Living/sleeping quarters
What Is an ADU Unit vs. a Shed?
The primary difference is the intent.
While a shed is for storage, an ADU is designed for people. It is built to the same rigorous building codes as a standard home, ensuring safety, comfort, and longevity.
Types of Accessory Dwelling Units
When considering an ADU, you generally have three paths to choose from:
- Detached ADUs: These are stand-alone structures separate from the main house. They offer the most privacy and are often built as prefab cottages or customized two-story garages.
- Attached ADUs: These are built as an addition to the side or back of the primary residence.
- Interior Conversions: This involves transforming existing square feet, such as a basement or attic, into a self-contained unit.
Why ADUs are the Future of Independent Living
The most common reason homeowners explore ADUs is to benefit their family members. We are seeing a massive trend toward multi-generational living, and for good reason.
Aging in Place
An ADU allows seniors to maintain their autonomy in an independent living space while just steps away from their children and grandchildren.
It provides peace of mind for the family without the feel of an assisted living facility.
Affordable Housing Solutions
With the cost of real estate soaring, many adults find it impossible to rent or buy their first home.
An ADU offers a high-quality, affordable housing option that keeps the family together while everyone enjoys their own “front door.”
Financial Benefits: Building Home Equity
Adding an ADU is one of the most effective home improvement projects for increasing your property’s value.
Unlike a swimming pool or a deck, an ADU adds actual livable square feet to your real estate portfolio.
- Increased Property Value: Appraisers recognize the value of a secondary dwelling, often significantly boosting your home’s resale price.
- Home Equity Loans: Many homeowners use a home equity loan or line of credit to finance the build. Since the project creates a tangible asset, it is often seen as a very secure investment.
- Passive Income: Depending on your local zoning laws, some homeowners use their ADU as a long-term rental, allowing the unit to essentially pay for itself over time.
Designing and Customizing Your Unit
Your ADU shouldn’t look like an afterthought; it should feel like a natural extension of your property.
Whether you are starting with a three-car garage foundation or a completely new footprint, customization is key.
You can match the siding, roofing, and architectural style of your main house to create a cohesive look.
Inside, modern ADUs feel surprisingly spacious. By using high ceilings, large windows, and open floor plans, even a unit with modest square feet can feel like a luxury home.
Pro Tip: Check out our guide on customizing prefab ADUs to see how you can balance style with functionality.
Take the Next Step Toward Your Dream ADU
Understanding “what is an ADU” is the first step toward reclaiming your property’s potential.
Whether you want to provide a home for your parents, create a guest house, or increase your home equity, an ADU is a versatile, beautiful solution.
At Lapp Structures, we specialize in helping homeowners navigate the journey from initial concept to the final coat of paint.
We take the stress out of the building process so you can focus on what matters: the people who will call that new space “home.”
Are you ready to see what’s possible for your backyard?