ADU Contractor in Paramount, CA
We know how much your home in Paramount, CA, means to you. That’s why we build ADUs that support real life—whether it’s for aging parents, grown kids, or someone just starting out.
Looking to Build an ADU in Paramount, CA? Start with Cornejos Builders
If you’re thinking about building an ADU in Paramount, maybe a granny flat, garage conversion, second-story addition, or a small bump-out, you want a team that knows what they’re doing and treats your home like it matters.
At Cornejos Builders, we’ve worked through the local codes, permits, and tricky lot layouts more times than we can count. We stick to realistic timelines, communicate clearly, and bring in experienced, approachable pros who genuinely care.
Whether it’s converting an attached garage into a guest suite or building something new in your backyard, we make sure every step is handled with care, precision, and accountability.
Alexsander Cornejo – Owner of Cornejo Builders
Hi, I’m Alexsander Cornejo, the owner and founder of Cornejo’s Builders. I started working in the remodeling and construction industry right out of high school, in 2009.
With Cornejo’s Builders, the goal is to give back to the city I grew up in. I want to send a message of hope and inspiration: any dream can be achieved, no matter where you come from, if you put in enough work and dedication.
Key Benefits
We’ve redefined what quality means in the accessory dwelling unit industry, raising the standard for craftsmanship and customer satisfaction. See what sets us apart:
- 1-year workmanship warranty
- Fast, predictable timelines
- Regular project updates
- Experienced, approachable crew
- Full-service ADU construction
- Support with financing & permits
See Our Work in Paramount, CA
Take a look at completed ADU projects in Paramount and nearby neighborhoods.
You’ll see how we balanced style and functionality—units with smart floor plans, ample natural light, efficient layouts, built‑in storage, well-chosen finishes, and seamless transitions to the backyard.
These examples will give you confidence that your vision is possible.
60+ projects done
100+ of families helped
1:1 approach to your project
What People in Paramount, CA Say About Us
Take a moment to read what homeowners in Paramount are saying about their experience building ADUs with us.
These are real stories from real families—people who trusted us with their homes and their goals. Their feedback means everything to us, and honestly, it says more than any marketing ever could.
L
Lety Ortega
Called Cornejo’s Builders after seeing their beautiful work on TikTok. Spoke to the owner regarding an ADU project.
Alex always returned my calls, explained throughly how the project would be completed. Love how his company is an all in one stop. They definitely handle everything from getting permits, architect, plumbing, electrical etc. Turn key ready, his prices are very reasonable and is willing to work around your budget. Alex was very understanding when I explained why I had to put a hold on the the project. He definitely treats his customers like family.
Y
Yahritza Orellana
Had a truly great experience with Alex. Cornejo’s Builders just completed converting my crawlspace/basement into an ADU (studio with new bathroom and kitchen).
What made the experience even more valuable was that the owner himself (Alex) came over for a consultation. Other companies just send their sales reps and most of the time they don’t even know anything. Feeling important is always a positive I can’t wait to work with them again. I highly recommend them. You can tell Alex is passionate about what he does, his clients, and his company.
How Much Does ADU Construction Cost in Paramount, CA?
ADUs in the region typically range from $80,000 to $250,000+, depending on size, finish level, and complexity. These are past estimates, not what we promise for yours.
Once we see your lot, design goals, and site constraints, we’ll deliver a project‑specific quote you can trust.
| Project | Included | Total Cost |
|---|---|---|
| Alhambra, CA (735 sq. ft.) | New foundation, plumbing, electrical, HVAC, Spanish style finishes, custom kitchen cabinets, separate utility connections | $250k |
| Whittier, CA (535 sq. ft.) | Central AC, open concept kitchen/living room, rental income property, custom finish bathroom tile, vinyl engineer flooring, level 5 drywall finish | $150k |
| Downey, CA (798 sq. ft.) | Vaulted ceilings, level 5 smooth finish, exterior stucco with smooth finish, customized electrical smart home finish, curbless walk-in shower, central AC | $200k |
Five factors that influence the cost of an ADU in Paramount, CA
Several factors can affect the cost of building an accessory dwelling unit in Paramount. Knowing what influences pricing helps you plan your project and budget with confidence.
- Size & layout
- Site access & foundation work
Tight backyards, grading, or poor soil push costs up.
- Finish quality & materials
Flooring, cabinetry, appliances, fixtures all scale the budget.
- Permits, codes & local fees
Paramount and L.A. County rules, impact fees, inspections, plan checks.
- Existing structure
Garage conversions typically cost less than building a new ADU from the ground up.
- Mechanical systems & utility hookups
Sewer, water, HVAC work can be major line items.
Budget-Friendly & On-Time Completion
We know construction can disrupt your home and routine, so we plan carefully, communicate clearly, and always respect your time and space.
Budget
We understand that you don’t want surprise ballooning costs. We plan with realistic buffers, pick durable materials without overspending, and keep you in the loop so changes are deliberate and not impulsive.
An ADU isn’t cheap—but it pays you back in ways that matter. Whether it’s rental income, space for family, or just the freedom to grow, it’s an investment that adds real value to your property and how you live.
Timeline
Construction can feel messy, but it doesn’t have to disrupt your life.
We aim to stick to agreed deadlines, maintain a clean site, and schedule around the Paramount climate (hot summers, occasional rain) so delays are minimized. You’ll feel the difference in communication and respect for your space.
Our ADU Construction Process
1
Collaborate
We design your ADU, pull permits, and plan everything—effortlessly handled.
2
Build
We manage construction, utilities, finishes, and inspections with care and craftsmanship.
3
Enjoy
Move in, rent, host—it’s ready to work for you from day one.
FAQs About ADU Contractor in Paramount, CA
How long does it take to build an ADU here?
Most ADUs take 4 to 8 months from permit to move-in, depending on size, site complexity, and finishes. If your lot is tricky (slope, tight yard, odd shape), it may take longer. We’ll give you a schedule you can rely on once we see your property.
Do you handle every trade—or will I need to coordinate subcontractors?
We handle it all—foundation, plumbing, electrical, framing, finishes, cabinetry. We manage every trade so you don’t have to jump between contacts. That means fewer surprises and clearer accountability.
Can I rent out the ADU, or is it just for family use?
Yes, in many cases an ADU can be rented (subject to local zoning and permit rules). We can help design the unit so it’s comfortable for guests or rental tenants, with good sound separation, privacy, and efficient layout.
What kind of warranty do you offer on ADU work?
We provide a 1‑year workmanship warranty on structural and finishing work, along with coverage for materials and systems. If something isn’t right, we’ll come fix it—no “we’ll see later” excuses.
Start Your Project with a Team You Can Count On
Alexsander Cornejos
Even small ideas can turn into something really useful. Let’s see what makes sense for your home.
Call us now at (562) 319-3178 or send us message here.
As your local ADU contractor, we believe in delivering integrity, quality, and clarity from day one..
Paramount, CA is a close-knit community in southeast Los Angeles County known for its small-town feel and deep roots in local history. Visitors often stop by the iconic Hay Tree, a California Historical Landmark tied to the city’s agricultural past, or catch a show at the Paramount Drive-In Theatres, one of the last of its kind in the region. It’s a city that balances everyday living with a touch of nostalgia and charm.