500 sq ft might not sound like a whole lot, but you can pack a lot of living space in this small area.
This is especially true for ADUs, which are designed with living and functional space in mind.
In this guide, we’ll walk you through some real examples of 500 sq ft ADU plans generated directly with Presite (our bespoke site plan software), as well as some considerations that are important at this size.
Let’s jump straight into it.
What is a 500 sq ft ADU?
An ADU, or Accessory Dwelling Unit, is a secondary housing unit on your property.
A 500 sq ft ADU is simply an ADU that has an internal area of 500 sq ft (no surprise there!).
This size is ideal for extra living space, rental income, or housing family members.
Is a 500 sq ft ADU a JADU?
A 500 sq ft ADU would technically be classed as a JADU, as a JADU has a maximum size of 500 sq ft.
Click here for our article on ADUs and JADUs to learn about the differences.
Benefits of a 500 sq ft ADU
You’d be surprised at just how much you can pack into 500 sq ft of space, and opting for a smaller ADU doesn’t have to be a compromise.
Cost-Effective
Smaller units mean lower construction costs.
ADUs can still be expensive even at a smaller size, but opting for a 500 sq ft design will help you save significant money on the construction.
Space Efficiency
500 sq ft ADUs are very space efficient, as you’ll see in our example designs listed below produced using Presite.
They’re able to contain an entire living space, as well as a bathroom, bedroom, kitchenette, and more, into one compact layout. You’d really be surprised at what you can fit into a small space when you have no other option.
Flexibility
500 sq ft ADUs are great for various uses—guest houses, home offices, rental units, or even downsized homes for aging parents.
Design and Layout Considerations
Designing a small space requires smart planning.
We don’t have much space to play with, so the following things become a lot more important:
- Open Floor Plans: The last thing we want to do is close up the already limited space, and open floor plans are perfect for combatting this.
- Storage Solutions: Built-in storage and multi-functional pieces of furniture are super handy in small spaces.
- Natural Light: Natural light really does help to make even small spaces feel light and airy.
Presite makes this entire process incredibly easy – you may also need to consult with an architect if you want a more custom ADU build.
500 sq ft ADU Floor Plans
Below are two examples of 500 sq ft ADU floor plans we have designed to get your imagination swirling on how a 500 sq ft ADU can look.
See our accompanying design notes below.
Example 500 sq ft ADU Floor Plan 1
1. Efficient Space, Zero Wasted Energy
At 500 square feet, every inch of this layout is designed to work for you.
There’s no dead space here—everything is intentional. The open-plan living area flows right into the kitchen, so you’re never more than a few steps from grabbing a snack or having a conversation while you cook.
This is the kind of design that says, “I don’t have time for wasted effort or clutter.”
2. Open-Plan Living in Action
We touched on this before, but open-plan living really does make all the difference with a smaller space.
The last thing we want to do is close up the space, and the open-plan layout of this design negates that perfectly.
3. Private Space Where You Need It
Look, we all need some privacy, right? That’s why the bedroom is tucked away in the corner. You get your own cozy retreat, away from the hustle of the living room.
And here’s the kicker: It comes with a walk-in robe (WIR). You get plenty of storage without cluttering up your bedroom—think Marie Kondo-approved efficiency.
4. Everything is Where It Should Be
Putting a little thought into the location of things like the bathroom and laundry goes a long way.
This plan keeps these next to each other, which makes plumbing and any future maintenance needed a breeze. The bathroom is also quite central, meaning it’s easy to access.
5. Light Up Your Life
Let’s talk windows. They’re everywhere you want them to be—bedroom, kitchen, living room.
You’re never going to feel trapped or boxed in. The natural light pouring in makes everything feel bigger and brighter.
Plus, with this many windows, you’ve got built-in cross-ventilation, meaning your home stays cool and fresh without needing to crank the AC all the time.
6. No Awkward Hallways
Here’s something you might not notice right away but will love over time: no long, awkward hallways.
The entry opens right into the main space. That’s extra square footage working hard to make the living area feel more expansive.
When you don’t have dead space dedicated to walking from one place to the next, you’ve got more room for the things you actually want to do—whether that’s chilling on the couch or entertaining guests.
7. Built to Adapt
This layout is a masterclass in flexibility.
It’s designed to work whether you’re living here full-time, using it as a guest house, or even renting it out on Airbnb. The open-plan design lets you play around with your furniture setup depending on your needs.
It’s like having a multi-tool in home form—compact, but ready for anything.
8. Big on Functionality
Here’s the thing: This home doesn’t just fit your life; it’s built for it.
It’s got everything you need, from a dedicated laundry area to a spacious living space that feels much larger than its 500 square feet.
You don’t need more space—you just need space that works better for you, and this floor plan is a prime example of how to do that.
Example 500 Sq Ft ADU Floor Plan 2
1. Bigger Bang for Your Buck—In Every Square Foot
This 500 sq ft layout is designed to give you everything you need, without overcomplicating things. Every square foot is working hard for you.
You’ll notice right away that nothing is wasted here.
It’s minimalism in action—but without feeling spartan or cramped. It’s for someone who values smart design that works.
2. Kitchen That’s All About Flow
The kitchen and dining area are perfectly placed for those who love efficiency (and maybe a little hosting). With this setup, you can easily transition from cooking to dining without missing a beat.
Plus, the circular table design is a nice touch—it’s space-saving and invites conversation.
Imagine gathering around this cozy spot for meals or coffee with friends—it’s intimate but never feels too small.
3. Separation of Space, Without Losing Connection
Here’s what’s genius: The bedroom is separated from the living area, giving you that coveted privacy, but it’s still easily accessible.
This really does make the space feel much more like a home, rather than an area designed purely for sleeping and eating.
4. Living Area That’s Open and Inviting
The living area opens up the space beautifully.
You’ve got enough room for a sofa and a TV setup, making it perfect for relaxing or even having a movie night. It’s open to the kitchen, so again—you’re not closed off or cramped in one spot, and can easily grab a snack while you watch your favorite film.
Everything feels airy and inviting, which is exactly what you want in a small home like this.
5. Smart and Convenient Laundry Setup
The laundry and bathroom are strategically placed near each other, keeping all the wet zones together, which just makes sense.
It also makes plumbing a hell of a lot easier, which is ideal if you encounter any issues further down the line.
Plus, having the laundry close to the kitchen means you can throw in a load while cooking dinner—multitasking, anyone?
6. Storage Where You Need It
While this design doesn’t present a full walk-in closet like the previous layout, it does provide a well-thought-out storage solution that makes perfect use of the available space.
7. Natural Light for Days
With windows in all the right places (living area, bedroom, kitchen), you’ll have tons of natural light flooding in. Natural light is key in making smaller spaces feel more expansive, and this design nails it.
This is a layout that knows how to make a room feel bigger simply by using windows and smart placement.
8. The Power of Open Concept, Without Feeling Overexposed
One of the things people love about open-concept designs is how free and easy everything feels.
But this layout manages to keep the openness while still giving you some privacy where it matters most. The bedroom feels like its own space, and you’re never too far from the bathroom, kitchen, or living area.
It’s a layout that gives you freedom without sacrificing the cozy factor, something which isn’t easily achievable with just 500 square feet of space to play with.
9. Efficient Entry That Makes Sense
Right when you enter, you’re greeted by a clear view of your space—not a hallway or some awkwardly placed wall.
You can see the living area, kitchen, and the open flow of the layout immediately, making it feel like home as soon as you step through the door.
It’s a subtle but important detail that sets the tone for the entire space.
Do You Need an Architect?
Hiring an architect may or may not be necessary – it all depends on what type of ADU you’re looking to build.
In general, there are two situations to consider:
- Pre-Approved Plans: Many cities (see Oakland, for example) offer pre-approved plans. These do not require an architect as they have already been designed by one (note that any changes needed will require an architect).
- Custom Designs: If you’re looking to do a custom ADU build, then you’ll need to hire an architect.
Our rundown of hiring an architect for an ADU project dives into this topic more thoroughly, so we’d recommend reading that if you need more information.
Cost Considerations
Building a 500 sq ft ADU is less expensive than larger units but still requires a clear budget.
Some key costs to keep in mind include:
- Construction: Varies based on materials, design complexity, and labor.
- Permits and Fees: Ensure you account for local building permits and impact fees.
- Utilities: Hooking up to existing utilities can add to the cost, especially if significant trenching or upgrades are needed.
This is where an architect or builder can be very useful, and also expect for there to be issues that arise during construction which can increase costs further.
FAQs
Can I use pre-approved plans for my 500 sq ft ADU?
Yes, many cities provide pre-approved plans, which can simplify the process and reduce costs.
How can I make a 500 sq ft ADU feel spacious?
The key to this is using open floor plans, incorporating plenty of natural light, and including smart storage solutions.
The designs shown previously are great examples of how you can achieve this in only 500 sq ft of space.
Wrapping It Up
Hopefully, you’ve got a better idea of 500 sq ft ADU plans now.
This size may seem small, but you can actually create an entire living space with all the utilities you need to live with just 500 square feet.
If you want to explore more 500 sq ft ADU plans, feel free to try out Presite – you can generate floor plans in seconds for any type of construction.