ADU Contractor
- 24 ADUs built in 4 years
- Fast completion timelines
- Constant project updates
- Seasoned and friendly pros
Scroll down to discover options, pricing, and process
Give Everyone You Love The Extra Living Space They Need
When we reach a certain age, our needs change as well. We’ll require more living space, a larger home, or an extra bedroom.
And if you want an ADU, one of the most important things to look for is quality.
Cornejo’s Builders don’t just deliver the highest-quality craftsmanship here in South California, but also a smooth and seamless construction experience you’ll love.
Here are some ADUs you can get:
- Granny flat
- Home addition
- Garage conversion
- ADU construction
- Bump-outs
- Porches and decks
- Second-story additions
- Attached garages
- Other conversions
Quality ADUs From A Trusted Pro
Frequently Asked Questions
Generally, we can build most ADUs in as quickly as 90 days. However, it’s important to understand that depending on the scope of work, complexity of the project, or your choice of materials and features, the timeline will increase.
To avoid any guesswork, we’ll give you an exact time frame after our on-site visit.
Everyone who will step on your property are trusted, local tradesmen. We only work with the best in the industry, all experts who have your best interests at heart.
Yes. However, it’s important to know that if you buy the materials yourself, this automatically voids the warranty.
If we’ll get the materials and install them for you, you’ll still enjoy their warranty, which can last anywhere from 1 year to a lifetime.
Of course! You’ll be able to see a 3D design of your new ADU so you don’t have to commit to any materials or design until you’re 100% satisfied with your upgrade.
The 3D renderings are included in our design-build process to ease your experience.
Yes! You’ll get a 1-year warranty on all new ADUs built by us, and the materials warranty on all materials that we’ll buy and use.
On top of that, you’ll always have our support, so whenever you need us again, you’ll have priority over anyone else.
A new ADU here in South California includes a kitchen, a bathroom, a living room, washer and dryer hook up, 1 bedroom or studio (depending on size of ADU), central heating, water, gas, and electrical installations.
We’ll take care of everything, and you’ll get a turnkey ADU that you can use the very same day we’re done working!
ADUs vary from $80,000 up to $250,000.00 depending on scope of work and size.
Ballparking the final cost is never a good idea, so it’s best to just request a free quote, have a consultation, and find out a realistic price for your upgrade.
Yes, all ADUs will require a permit here in South California. No need to worry though. Cornejo’s Builders Inc. handles all planning, permitting, and construction, so you don’t have to worry about anything.
Just sit back, relax, and watch your dream home come to life.
Top benefits of building an ADU:
- Small enough to fit on smaller inner city lots and large estate properties
- Turn-key solutions for both design & construction
- Can be converted, attached, or detached to your existing house
- Built off-site in 90 days and delivered to your residence
- Little or no debt and reduced expenses, ready to move in
ADU Pricing Insights Here In South CA
While ballparking an estimate never works out, we still want to show you what some of our ADU projects include and what they look like. Check below!
New 735 sq. ft. Two-Story ADU in Alhambra, CA
- New foundation
- New plumbing
- New electrical
- New HVAC
- New Spanish style finishes
- New custom kitchen cabinets
- New separate Utility connections
New 535 sq. ft. ADU in Whittier, CA
This project included:
- New central AC
- New open concept kitchen/living room
- New rental income property
- New custom finish bathroom tile
- New vinyl engineer flooring
- New level 5 drywall finish
New 798 sq. ft. ADU in Downey, CA
- New vaulted ceilings
- New level 5 smooth finish
- Smooth finish on exterior stucco
- Customized electrical smart home finish
- Curbless walk-in shower
- Central AC
This project was quoted at $200,000, where the most expensive item was the bathroom tile which came out to be $8,000.
Fully Enjoy The Excitement Of Your Home Upgrade
Let’s take you on a beautiful experience where all you need to do is enjoy your new ADU. This 3-step process ensures a smooth and stress-free experience, start to finish.
1
Collaborate
Contact us and let’s plan your ADU together with our designers.
2
Build
Remain comfortable and on top of everything at all times.
3
Enjoy
Have everyone over for dinner and enjoy your new ADU!
A Lifelong Partnership With A Reliable Expert
Guarantee your project’s success with an expert who puts you and your investment first. Our continuous education ensures we deliver on our promise every single time.
Lanny Lam
Cornejo’s Builders did an amazing job remodeling our kitchen. Alexsander made this experience one of a kind, he was accessible and flexible throughout the process.
This guy’s knowledge truly guided us to perfect our dream kitchen. He has endless recommendations. The workers were efficient. We appreciate how he handled minor changes we had with professionalism.
After getting work done by different General Contractors, Cornejo’s Builders definitely sets the bar for the rest. Thank you, Alexsander.
L
Lety Ortega
Called Cornejo’s Builders after seeing their beautiful work on Tik Tok. 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.
The Perks Of A Seasoned ADU Contractor In South CA
Take advantage of the best perks of working with a local, trusted ADU professional here in Downey, San Marino, and surrounding areas.
- Peace Of Mind
Everyone involved in your project is 100% committed to your satisfaction. You’ll be treated with utmost respect 24/7.
- Quality Craftsmanship
You’ll enjoy the best tradesmen here in South California, all ready to deliver the best product you could ever find around here.
- Dialed-in Processes
Remain comfortable while fully enjoying the excitement of getting an ADU. We have the know-how to make it happen!