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Alexsander Cornejo

Hi, I’m Alexsander Cornejo, the owner and founder of Cornejo’s Builders. I started working in the remodeling and construction industry with my dad, 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.

Hi, I’m Alexsander Cornejo, the owner and founder of Cornejo’s Builders. I started working in the remodeling and construction industry with my dad, 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.

Get a Quote
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Background

Alexander, graduated from Cal State Long Beach began his construction career in 2009. Instead of pursuing a different path, he entered the workforce and trained alongside his father, learning the trade from the ground up through hands-on experience in remodeling and construction.

Experience & Recognition

With 15+ years of experience, Alexander has completed over 60 projects and supported more than 100 families across Southern California and now OSHA Certified. Known for his hands-on leadership, he personally oversees consultations and inspections, earning recognition as a trusted ADU and home building contractor.

Areas of Expertise

Alexander specializes in ADUs, custom homes, and residential remodels, including kitchens and bathrooms. He manages the full project lifecycle, from architectural design and AI 3D renderings to permits and final construction, leading a bilingual team focused on quality and long-term value.

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.

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Andrei Hienadz

Andrei Hienadz

★★★★★ Rated 5 out of 5

I had a fantastic experience with Cornejos Builders! They exceeded my expectations in every way.  From the initial consultation to the final walkthrough, their professionalism and
craftsmanship shone through.

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Ronda Welker

★★★★★ Rated 5 out of 5

We couldn’t have asked for a better contractor to work with than Alex. 

We were needing our home remodeled in a very short window of time and Alex and his crew were always on schedule and in touch with us throughout the whole remodel. 

We would definitely use them again.

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Marco Urbana

★★★★★ Rated 5 out of 5

Really good and professional company I love the fact that they are bilingual several companies came our to give a estimate but they were by far the most qualified and did a great job.

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Get In Touch

  • Cornejos Builders ADU Construction & Home Building
  • 8909 Elmont Ave. Downey, CA 90240
  • (562) 319-3178
  • alex@cornejosbuilders.com
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Get In Touch

  • Cornejos Builders ADU Construction & Home Building
  • 8909 Elmont Ave. Downey, CA 90240
  • (562) 319-3178
  • alex@cornejosbuilders.com

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