Can I combine a detached State ADU with an attached Ordinance ADU on my LA single-family lot, and what’s the max square footage for each?

Lisa T.
May 20, 2025 at 11:19 PM
Cost & Budget Los Angeles, CA
Hey everyone,

I'm diving into the world of ADUs here in LA and could use some advice. I'm considering combining a detached state ADU with an attached ordinance ADU on my single-family lot. Has anyone done this before? What’s the max square footage allowed for each? I’m trying to figure out how to maximize my space without breaking the bank. Any tips on budgeting for this kind of project would be super helpful too. I’m aiming to create some rental income and maybe a guest space for family visits. Thanks in advance for any insights!

Cheers,
Lisa

1 Answer

Amanda (GatherADU Team)
May 22, 2025 at 03:19 AM
Hi, Amanda from GatherADU! Yes, you can combine a detached State ADU (max 800 square feet) with an attached Ordinance ADU (up to 850 square feet, or 1,000 for multiple bedrooms) on a single-family lot, as allowed by the ZA Memo. Just ensure each meets its respective standards (e.g., 4-foot setbacks for the State ADU). Need help crunching the numbers for your lot? We’re here!
Didn't find what you're looking for?

Need help with ADU plans, permits, or finding contractors? Our experts are here to guide you through the entire process.

Book Free Call
or call: (323) 591-3717
Your Answer
Email will not be displayed publicly
Provide a helpful, detailed answer. Be respectful and constructive.
CAPTCHA
Enter the characters shown above
* Required fields

Ready to Start Your ADU Project?

Get a personalized quote based on your specific needs and location. Our experts will guide you through every step of the process.

Get Instant Quote
Free consultation included • No obligation

Types of ADUs in Los Angeles, CA

Understanding the different types of Accessory Dwelling Units can help you choose the best option for your property and needs.

Detached ADU

A separate, standalone structure built on your property. Offers maximum privacy and flexibility for tenants.

  • Complete privacy
  • Custom design options
  • Higher rental income potential
Attached ADU

An addition to your existing home with a separate entrance. Cost-effective option with shared utilities.

  • Lower construction costs
  • Shared utility connections
  • Family-friendly proximity
Garage Conversion

Convert existing garage space into a livable unit. Most cost-effective ADU option with fastest approval.

  • Lowest construction cost
  • Faster permitting
  • Uses existing structure
JADU

Junior ADU created within the existing home. Maximum 500 sq ft with efficiency kitchen and shared utilities.

  • Minimal construction
  • No parking requirement
  • Perfect for family use
Upper Floor ADU

Add a second story or convert existing upper floor space. Maximizes property value and rental potential.

  • Premium rental rates
  • Enhanced privacy
  • Great city views
Basement ADU

Convert basement or lower level into living space. Great option for properties with existing below-grade areas.

  • Uses existing space
  • Natural temperature control
  • Sound isolation

ADU Cost Guide for Los Angeles, CA

Understanding ADU costs helps you budget effectively and make informed decisions about your project. Costs vary based on size, complexity, and local factors.

ADU Type Size Range Cost Range Timeline Best For
Garage Conversion 400-800 sq ft $80K - $150K 3-6 months Budget-conscious homeowners
JADU Up to 500 sq ft $50K - $100K 2-4 months Family use, minimal disruption
Attached ADU 600-1,000 sq ft $120K - $200K 4-8 months Shared utilities, family proximity
Detached ADU 600-1,200 sq ft $150K - $300K 6-12 months Maximum rental income
Two-Story ADU 800-1,500 sq ft $200K - $400K 8-15 months Maximizing property value
Cost Factors to Consider
  • Site Preparation: $5K - $25K
  • Permits & Fees: $3K - $15K
  • Utility Connections: $5K - $20K
  • Finish Level: $10K - $50K variance
  • Landscaping: $2K - $10K
Potential ROI
  • Rental Income: $1,500 - $4,000/month
  • Property Value Increase: 20-30%
  • Payback Period: 8-15 years
  • Tax Benefits: Depreciation allowances
  • Equity Growth: Long-term appreciation
Get Your Personalized Cost Estimate

These are general ranges. Your actual costs may vary based on specific site conditions, design choices, and local market factors in Los Angeles.

Get Detailed Quote

Why Build an ADU in Los Angeles?

Financial Benefits
Rental Income: Generate $18,000-$48,000 annually
Property Value: Increase home value by 20-30%
Tax Benefits: Depreciation and expense deductions
Investment: Strong ROI in California markets
Lifestyle Benefits
Multigenerational Living: Keep family close while maintaining privacy
Home Office: Create dedicated workspace or studio
Guest Space: Comfortable accommodations for visitors
Sustainability: Increase housing density efficiently

Popular ADU Floor Plans

Explore our most popular ADU designs that work well in Los Angeles, CA. These professionally designed floor plans optimize space and functionality while meeting local building requirements.

Cascade ADU Floor Plan - 2 Bedroom, 2 Bathroom
2 Bed 2 Bath 1,200 sq ft
The Cascade

Spacious 2-bedroom design perfect for families. Features open living area, full kitchen, and two full bathrooms with optimal privacy.

Open floor plan
Master suite
Laundry room
Summit ADU Floor Plan - 2 Bedroom, 2 Bathroom
2 Bed 2 Bath 950 sq ft
The Summit

Efficient 2-bedroom layout maximizing every square foot. Great for narrow lots with smart storage solutions throughout.

Compact design
Pantry storage
Two full baths
Brookside ADU Floor Plan - 2 Bedroom, 2 Bathroom
2 Bed 2 Bath 1,400 sq ft
The Brookside

Luxurious 2-bedroom design with premium features. Includes master suite, guest bedroom, and spacious living areas.

Large living room
Walk-in closets
Full kitchen island
Sequoia ADU Floor Plan - 3 Bedroom, 2 Bathroom
3 Bed 2 Bath 1,100 sq ft
The Sequoia

Unique 3-bedroom configuration perfect for larger families. Features dual bathrooms and smart space utilization.

Three bedrooms
Laundry room
Multiple closets
Crestline ADU Floor Plan - 3 Bedroom, 2 Bathroom
3 Bed 2 Bath 1,500 sq ft
The Crestline

Premium 3-bedroom layout with maximum comfort. Features spacious bedrooms, walk-in closets, and luxury finishes.

Primary suite
Pantry space
Open concept
Ready to Explore More ADU Designs?

Browse our complete collection of ADU floor plans with detailed specifications, 3D renderings, and customization options.

View All Floor Plans

Complete Guide to Cost & Budget ADUs in Los Angeles, CA

Understanding Cost & Budget for ADU Projects

Understanding ADU costs and budgeting effectively is essential for project planning in Los Angeles, CA. Construction costs vary based on size, complexity, site conditions, and local market factors.

Budget considerations include design fees, permit costs, site preparation, construction materials, labor costs, utility connections, and contingency reserves. Hidden costs often arise during construction, so proper planning and realistic budgeting are crucial.

Financial planning should also consider potential return on investment through rental income or increased property value. Professional cost estimation helps ensure your project remains financially viable throughout the construction process.

Cost & Budget Requirements in Los Angeles, CA

Local regulations in Los Angeles, CA have specific requirements that affect ADU development. Understanding these local nuances is crucial for project success and compliance.

Los Angeles has 102 ADU-related questions in our database, indicating active development interest in your area. This local activity suggests growing expertise among contractors, architects, and city officials familiar with ADU projects.

Common considerations for Los Angeles include local architectural standards, historical district requirements if applicable, utility connection procedures, and neighborhood-specific zoning overlays that may affect your project.

Expert Insights on Cost & Budget

The GatherADU team has helped hundreds of homeowners navigate cost & budget challenges successfully. Our experience reveals common patterns, effective strategies, and potential pitfalls to avoid.

Professional consultation early in your project can prevent costly mistakes and delays. We've seen how proper planning in the cost & budget phase saves both time and money throughout the entire ADU development process.

Our database contains 9 questions related to Cost & Budget, with 12 expert answers providing comprehensive guidance for homeowners facing similar challenges.

Ready to Move Forward with Your ADU Project?

Don't let cost & budget challenges delay your ADU dreams. Our experts can provide personalized guidance specific to your situation in Los Angeles, CA.

More Cost & Budget Questions & Answers

Explore additional cost & budget questions from our community to gain deeper insights into ADU development challenges and solutions.

Can I build an ADU in Burbank with a shared wall less than 5 feet long?
Burbank, CA 1 answers

Burbank ADU question here - development fees is what I'm trying to figure out. I want to maximize th...

June 22, 2025
How much does it cost to build an ADU in San Francisco?
San Francisco, CA 2 answers

I'm looking to build an ADU in my backyard in San Francisco. My lot is about 5,000 sq ft and I'm thi...

June 21, 2025
Can I avoid impact fees for my 700-square-foot ADU in LA, or do they still apply for smaller units?
Los Angeles, CA 1 answers

Can I avoid impact fees for my 700-square-foot ADU in LA, or do they still apply for smaller units?

June 04, 2025
How do I figure out my single-family home’s square footage for ADU impact fees over 750 square feet in LA? Can I just use the County Tax Assessor’s records?
Los Angeles County, CA 2 answers

Hey everyone! 👋 So I'm kinda stuck on figuring out the square footage of my single-family home for A...

May 17, 2025
Can I build a 900-square-foot ADU in Glendale without paying development impact fees?
Glendale, CA 1 answers

Can I build a 900-square-foot ADU in Glendale without paying development impact fees?

May 15, 2025
My Glendale multifamily building is multi-story. Can my detached ADUs be 18 feet tall?
Glendale, CA 1 answers

My Glendale multifamily building is multi-story. Can my detached ADUs be 18 feet tall?

April 25, 2025
My LA Ordinance ADU is 900 square feet. Do I need to pay school fees, and how are they calculated?
Los Angeles, CA 2 answers

My LA Ordinance ADU is 900 square feet. Do I need to pay school fees, and how are they calculated?

April 24, 2025
My Glendale ADU will be 600 square feet. Do I need to pay school fees?
Glendale, CA 1 answers

My Glendale ADU will be 600 square feet. Do I need to pay school fees?

April 13, 2025

ADU Questions from Los Angeles, CA

Discover how other homeowners in Los Angeles, CA are approaching their ADU projects. Local insights can provide valuable context for your own planning.

test 234
Permits & Regulations 0 answers

testing 456

June 23, 2025
ADU permit timeline in Los Angeles - what to expect?
Permits & Regulations 2 answers

We're planning to convert our detached garage into an ADU in LA. The garage is about 400 sq ft and w...

June 21, 2025
How do I check if my LA ADU project vested under old rules before the 2019 ADU Ordinance, and can I switch to new rules?
General Advice 1 answers

How do I check if my LA ADU project vested under old rules before the 2019 ADU Ordinance, and can I ...

June 20, 2025
Can I build a Movable Tiny House as an ADU in LA without following building code rules for regular structures, and what standards still apply?
Construction 2 answers

Hey everyone! I'm looking into building a tiny house on wheels as an ADU in my backyard here in LA....

June 19, 2025
Can I turn a storage room in my LA multifamily building into a State ADU without worrying about local parking or open space rules?
Parking & Access 1 answers

Hey everyone! So I'm thinking about converting a storage room in my multifamily building in LA into ...

June 18, 2025
If my LA multifamily building has 20 units, how many attached State ADUs can I add by converting unused spaces like attics or basements?
Construction 1 answers

Title: Converting Unused Spaces into ADUs in LA - How Many Can I Add? Hey everyone, I'm looking in...

June 15, 2025

Related ADU Questions

These questions share similar topics or locations and may provide additional insights for your ADU project.

test 234
Permits & Regulations Los Angeles, CA
0 answers Jun 23, 2025
Can I build an ADU in Burbank with a shared wall less than 5 feet long?
Cost & Budget Burbank, CA
1 answers Jun 22, 2025
ADU permit timeline in Los Angeles - what to expect?
Permits & Regulations Los Angeles, CA
2 answers Jun 21, 2025
How much does it cost to build an ADU in San Francisco?
Cost & Budget San Francisco, CA
2 answers Jun 21, 2025

ADU Development Checklist for Los Angeles, CA

Use this comprehensive checklist to ensure you don't miss important steps in your ADU development process.

Planning Phase
  • Define project goals and budget
  • Research local zoning requirements
  • Evaluate site conditions and constraints
  • Consult with ADU experts
  • Develop preliminary design concepts
Pre-Construction
  • Finalize architectural plans
  • Submit permit applications
  • Select qualified contractors
  • Secure financing if needed
  • Schedule utility connections
Construction Phase
  • Site preparation and excavation
  • Foundation and framing work
  • Rough-in electrical and plumbing
  • Insulation and drywall installation
  • Interior and exterior finishes
Completion
  • Final inspections and approvals
  • Certificate of occupancy
  • Utility meter installation
  • Final walkthrough and cleanup
  • Property insurance updates
Need Help with Your ADU Checklist?

Our experts can provide personalized guidance for each phase of your Los Angeles ADU project, ensuring nothing falls through the cracks.

Get Expert Project Guidance
Get Expert Help

Stuck on your ADU project? Get personalized guidance from our experts.

Free 15-minute consultation available
Related Topics
Cost & Budget Los Angeles ADU Planning Permits
Los Angeles, CA

This question is specific to Los Angeles, CA

Local regulations may vary by jurisdiction. Always verify with your local planning department.