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Alexsander Cornejo

Alexsander Cornejo is the owner and founder of Cornejos Builders Inc., a home construction & ADU company based in Downey, CA. He began his career in the remodeling industry in 2009, starting work alongside his father. Alexsander specializes in building Accessory Dwelling Units (ADUs) and custom homes, tailoring projects to meet the unique housing needs and lifestyles of Southern California residents

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Meet 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.

Education

Alexsander’s practical education in the trade began immediately following his graduation from high school in 2009,. Rather than pursuing a different path, he entered the workforce straight away, launching his career in the remodeling and construction industry by working alongside his father to learn the trade from the ground up,

Professional Experience & Recognition

With over 15 years of experience since starting in 2009, Alexsander has completed over 60 projects and assisted more than 100 families throughout Southern California,. He is recognized for his hands-on leadership, often performing on-site consultations and detailed home inspections personally rather than sending sales representatives,. His company is consistently rated as a top contractor for ADUs and home building in cities such as Downey, Whittier, Norwalk, and Bell Gardens,,,

Areas of Expertise

Alexsander specializes in constructing Accessory Dwelling Units (ADUs), custom homes, and extensive residential remodels, including kitchens and bathrooms,. He operates as a “one-stop shop,” managing the full project lifecycle from architectural design and 3D renderings to navigating city permits and final construction,,. Additionally, he leads a bilingual team capable of executing turnkey projects that maximize property value and functionality,

alexsander-cornejos2

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.

Get a Quote
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Education

Alexander began his construction career immediately after graduating 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. 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 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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M

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

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