In-law suites, granny flats, backyard cottages… ADUs have had many names. Accessory Dwelling Units (ADUs) are transforming the housing landscape in California. They provide new ways to expand beyond the main house, earn extra income, and live more flexibly, all while showcasing beautiful design.
Types of ADUs
Detached ADUs: Standalone backyard structures (DADUs) perfect for guest houses or rentals.
Attached ADUs: Built as extensions to the primary home, sometimes with separate entrances.
Garage Conversion ADUs: Transformed garages or built-above units using existing structures.
Internal ADUs: Basement or attic spaces converted into private living quarters.
Junior ADUs (JADUs): Compact units (max 500 sq. ft.) within the main home, often sharing utilities or a bathroom.
Each type offers unique benefits depending on space, budget, and household needs.
How Much Does an ADU Cost in California?
ADU construction costs vary widely depending on the type, location, and materials used. On the West Coast, especially in California, you can expect to spend between $150 to $600 per square foot.
Basic garage conversions or prefab units: $60,000–$150,000
Custom-built detached ADUs: $200,000–$360,000
Cost-saving tips:
Renovate existing structures like garages or basements.
Use prefab plans already approved by your city.
Install energy-efficient fixtures and appliances.
DIY interior finishes like painting or decorating.
California’s CalHFA ADU Grant Program also offers up to $40,000 in reimbursements for pre-development costs.
Why Build an ADU?
There’s a reason ADUs are popping up across California; they make sense. Whether you're looking for flexibility, a place for loved ones, or a smart way to boost your property value, ADUs deliver big impact in a small footprint.
Here’s why so many homeowners and designers love ADUs:
Make extra income by renting your ADU, whether long-term or as a short-term vacation rental.
Keep family close with a private suite for aging parents, college kids, or out-of-town guests.
Go green with a smaller home that uses fewer materials and less energy.
Add serious value to your property, up to 30%, especially with detached units.
Create space for yourself like a peaceful home office, art studio, or wellness retreat.
Adapt to life’s changes, whether that’s welcoming a new family member or launching a side hustle.
And with ADUs now easier to build than ever, the timing has never been better.
California’s ADU Boom
A few years ago, building an ADU in California meant headaches: strict zoning rules, high permit fees, and lots of red tape. But that’s changing fast.
Thanks to new statewide laws (like SB 477, passed in 2024), local restrictions have relaxed, and more cities are actively supporting ADU development. This means:
Faster permitting
Fewer zoning barriers
Pre-approved building plans
More financing options and grants
From Los Angeles to San Jose, cities are recognizing that ADUs are a real solution to the housing crunch. Designers are now collaborating closely with homeowners to create beautiful, functional spaces that enhance both lifestyle and value.
Bring California Vibes into Your ADU
Designers are using California’s signature aesthetic – laid-back, sun-soaked, and modern – to make ADUs feel like dreamy hideaways. If you want to channel California style, try these tips:
Use light colors like
and Desert Oak along with natural textures to keep things airy.
Embrace open layouts that flow easily.
Incorporate indoor-outdoor connections with large windows or patio doors.
Choose multi-functional furniture to maximize space.
Think minimalist, modern, and breezy, with just the right touches of warmth. Check out the Top California Design Trends of 2025 for more inspo!
Style Your ADU Seamlessly with Fabuwood Cabinets
When every square inch counts, smart cabinetry makes all the difference. From our modern space-saving Illume series to smart storage, we offer options that fit beautifully in kitchens, bathrooms, and whole homes. Our wide variety of door styles and over 100 finishes help create a cohesive look across the ADU and the main home.
FAQS
Q: Do I need a permit to build an ADU? A: If it’s habitable living space, you’ll need one. The good news? California has made the process faster and easier in recent years.
Q: How big can my ADU be? A: Most cities in California allow detached ADUs up to 800 square feet and 16 feet tall, but it can vary. Check your local guidelines.
Q: Can I rent out my ADU? A: Absolutely. Many homeowners rent their ADUs for steady income. Be sure to follow local rules for both long-term and short-term rentals.
Q: What’s a JADU? A: A Junior ADU is a smaller, internal unit (up to 500 sq. ft.) inside your main home. It might share a bathroom or utilities and is super budget-friendly to build.
Q: What’s the difference between an ADU and a tiny home? A: Tiny homes can be mobile and placed anywhere. ADUs must be on the same lot as a primary residence and built to code.
