Blog Single

In Los Angeles, Accessory Dwelling Units (ADUs) have become a game-changer for homeowners looking to create extra living space, generate rental income, or support multi-generational families. Two of the most popular options are Garage Conversions and Backyard (Detached) ADUs—but which one is better?

The short answer? It depends on your property, goals, and budget. In this guide, we’ll break down the key differences between a garage ADU and a backyard ADU so you can make the best decision for your Los Angeles home in 2025.

What Is a Garage ADU?

A Garage ADU is a converted existing garage—either attached or detached—transformed into a fully livable space. These units typically include a kitchen, bathroom, bedroom, and living area. They’re often more cost-effective than building a new structure from scratch and can be completed relatively quickly.

Pros of Garage ADUs

1. Lower Construction Costs
Since the structure already exists, garage conversions typically cost less than building a detached unit. You save on foundation, framing, and roofing.

2. Faster Permitting and Build Time
Garage ADUs in LA can often bypass lengthy structural reviews if the existing building is up to code.

3. Easier Utility Hookups
Garages are already close to your main house, making plumbing, electricity, and HVAC connections simpler.

4. Higher ROI Potential
Garage conversions can add rental value with a relatively low upfront investment—ideal for generating passive income.

Cons of Garage ADUs

1. Limited Space
Most garages in LA range from 200–400 square feet. If you need more space, a detached ADU may be better.

2. Design Restrictions
Because you’re working within an existing structure, your layout options may be more limited.

3. Reduced Storage or Parking
You’ll lose garage storage or vehicle space, which can affect resale value or trigger HOA/parking concerns in certain neighborhoods.

What Is a Backyard ADU?

A Backyard ADU, also known as a detached ADU or standalone ADU, is a new, fully separate building located in the rear or side yard of your property. These units offer total privacy and more design flexibility.

Pros of Backyard ADUs

1. More Customization
Since you’re starting from scratch, you can design the space exactly how you want—from layout to finishes to square footage (up to 1,200 sq ft in LA).

2. Complete Privacy
A detached ADU offers more separation from the main home—ideal for renters, guests, or aging parents.

3. Long-Term Value
A well-designed backyard ADU can significantly boost your home’s resale value and rental appeal.

4. Multi-Use Potential
Backyard ADUs can double as guest houses, studios, Airbnb rentals, or home offices, depending on your needs.

Cons of Backyard ADUs

1. Higher Costs
Expect to spend more due to site work, new foundation, framing, roof, and separate utility runs.

2. Longer Timeline
Permitting and construction can take several months, especially if soil grading or utility upgrades are needed.

3. More Space Required
You’ll need enough backyard space to meet setback requirements and still leave room for landscaping or outdoor living.

Cost Comparison in Los Angeles (2025 Estimates)

ADU Type	Avg. Cost Range	Avg. Time to Build	Size Range
Garage ADU	$80K – $160K	3–6 months	200–400 sq ft
Backyard ADU	$160K – $350K+	6–12 months	400–1,200 sq ft

Keep in mind that costs vary based on materials, finishes, permits, utility upgrades, and location.

Which One Is Better for You?

Choose a Garage ADU if:

• You’re on a tight budget
  
• You want faster returns through rental income
  
• You don’t need much space
  
• Your garage is already structurally sound
  

Choose a Backyard ADU if:

• You want more privacy or a larger space
  
• You plan to house long-term family members
  
• You want to design a high-end unit
  
• You have ample yard space and a higher budget

Permitting Considerations in Los Angeles

Thanks to California’s ADU-friendly laws (SB 9, SB 897), it’s now easier to build either type of ADU. However, zoning requirements still apply:

• Minimum setbacks: 4 feet from side and rear lot lines for detached ADUs
  
• Max size: 1,200 sq ft or 50% of the main home’s size (whichever is less)
  
• No impact fees for units under 750 sq ft
  
• One ADU and one JADU allowed per residential lot in most LA zones
  

Before starting, check with LADBS (Los Angeles Department of Building and Safety) for the most current ADU codes and site-specific regulations.

Final Thoughts

Both garage and backyard ADUs offer unique benefits. If you want to add livable space quickly and cost-effectively, a garage ADU is a smart move. If you’re thinking long-term and want maximum flexibility, a backyard ADU may be worth the extra investment.

Either way, building an ADU in Los Angeles is a smart strategy in 2025—whether for passive income, aging in place, or growing your property’s value in a competitive market.

Ready to decide? Talk to an ADU specialist or architect familiar with LA’s codes and start designing your perfect secondary unit today.