ADU Contractors
Dashboard

ADU Builders & Contractors in Downey, CA

Building an ADU in Downey? You'll find 259 licensed contractors in the area, ready to help. Downey's ADU market continues to grow as homeowners invest in additional living space, rental income, and multi-generational housing.

📊 ADU Quick Facts for Downey

Avg. Cost/sqft

$198-$373

Permit Timeline

60-120 weeks

Max Size

1200 sqft

Setbacks

4ft sides

Top 259 ADU Contractors in Downey

🏗️
#1GREENTECH DEVELOPMENT INC

Downey, CA

Greentech Development Inc — licensed ADU contractor in Downey, CA. Detached ADU construction. 5+ years experience.

View Profile📞 (562) 706 6936
🏗️
#2ECHELON CONSTRUCTION LLC

Downey, CA

Echelon Construction Llc — licensed ADU contractor in Downey, CA. Detached ADU construction. 9+ years experience.

View Profile📞 (818) 903 9037
🏗️
#3MACIAS CONSTRUCTION CO

Downey, CA

Macias Construction CO — licensed ADU contractor in Downey, CA. Detached ADU construction. 37+ years experience.

View Profile📞 (562) 658 6194
🏗️
#4JOE WILLIE CORPORATION

Downey, CA

Joe Willie Corporation — licensed ADU contractor in Downey, CA. Detached ADU construction. 8+ years experience.

View Profile📞 (323) 365 7512
🏗️
#5R & E CONSTRUCTION SERVICES INC

Downey, CA

R & E Construction Services Inc — licensed ADU contractor in Downey, CA. Detached ADU construction. 9+ years experience.

View Profile📞 (909) 485 7099
🏗️
#6CHAVEZ UNLIMITED CONSTRUCTION INC

Downey, CA

Chavez Unlimited Construction Inc — licensed ADU contractor in Downey, CA. Detached ADU construction. 17+ years experience.

View Profile📞 (714) 720 3588
🏗️
#7DESIGNER BUILDERS INC

Downey, CA

Designer Builders Inc — licensed ADU contractor in Downey, CA. Detached ADU construction. 21+ years experience.

View Profile📞 (213) 923 1700
🏗️
#8M A R CONSTRUCTION

Downey, CA

M A R Construction — licensed ADU contractor in Downey, CA. Detached ADU construction. 19+ years experience.

View Profile📞 (323) 919 6479
🏗️
#9SUN-ROCK BUILDER CORPORATION

Downey, CA

Sun-Rock Builder Corporation — licensed ADU contractor in Downey, CA. Detached ADU construction. 8+ years experience.

View Profile📞 (562) 361 6288
🏗️
#10C I R IMPROVEMENT

Downey, CA

C I R Improvement — licensed ADU contractor in Downey, CA. Detached ADU construction. 26+ years experience.

View Profile📞 (562) 547 9740
View All 259 Contractors →

💰 How Much Does an ADU Cost in Downey?

Garage Conversion

$69,000 - $129,000

Converting existing garage to living space

Detached ADU

$148,000 - $323,000

New standalone unit (600-1,200 sqft)

Permit & Fees

$1,111 - $5,111

Plan check, permits, utility connections

* Costs vary based on size, finishes, site conditions, and contractor. Get quotes from multiple Downey contractors to compare pricing.

❓ Frequently Asked Questions About ADUs in Downey

How much does it cost to build an ADU in Downey?▼
The average cost to build an ADU in Downey ranges from $148,000 to $323,000, or approximately $198 to $373 per square foot. Garage conversions typically cost $69,000 to $129,000.
How long does it take to get an ADU permit in Downey?▼
The ADU permit process in Downey typically takes 60 to 120 weeks. California law requires cities to approve or deny ADU permits within 60 days of receiving a complete application.
What are the ADU size limits in Downey?▼
In Downey, detached ADUs can be up to 1200 square feet. Attached ADUs are limited to 50% of the primary dwelling or 1,200 sqft, whichever is less. Junior ADUs (JADUs) are limited to 500 sqft and must be within the existing home.
What is the setback requirement for ADUs in Downey?▼
Downey requires 4-foot setbacks from side property lines and 4-foot setbacks from rear property lines for new ADU construction. Converted structures (like existing garages) may maintain their current setbacks.
Do I need to provide parking for my ADU in Downey?▼
No parking is required for ADUs in Downey if your property is within half a mile of public transit, in a historic district, part of an existing multi-family building, or if the ADU is a garage conversion. Otherwise, one space may be required.

Also See ADU Contractors In

Los Angeles (3215)San Diego (2582)San Francisco (2170)Sacramento (1551)Riverside (925)Fresno (904)Anaheim (784)Irvine (760)

Ready to Build Your ADU in Downey?

Get free quotes from top-rated local contractors

Find Contractors Now
← View all contractors in California