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Find Addition to existing structure builders in Ontario

Avatar for Socal Express Restoration and Construction Inc.

Socal Express Restoration and Construction Inc.

New on HomeAdvisorNew on HomeAdvisor
Approved Pro

Socal Express Restoration and Construction Inc.

New on HomeAdvisorNew on HomeAdvisor
Approved Pro
6 years of experience
Free onsite estimate

We are an ethical, honest and professional company. We are easy to communicate with. Always working with you until the job is done right and to your specifications. When working with our company you can expect integrity, prompt service and superior customer service. Always leaving the job site clean . We take pride in our services and enjoy making clients repeat clients. You can count on us to get the job done right the first time. We will meet with you at your convenience and will not keep you waiting. Call us today for your free estimate. You'll be pleased you did. Thank you

We are an ethical, honest and professional company. We are easy to communicate with. Always working with you until the job is done right and to your specifications. When working with our company you can expect integrity, prompt service and superior customer service. Always leaving the job site clean . We take pride in our services and enjoy making clients repeat clients. You can count on us to get the job done right the first time. We will meet with you at your convenience and will not keep you waiting. Call us today for your free estimate. You'll be pleased you did. Thank you


Avatar for David's Builders, Inc.

David's Builders, Inc.

5.00(
4
)
Approved Pro

David's Builders, Inc.

5.00(
4
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
12 years of experience

David's Builders, Inc., is a locally owned and operated company that values honesty and integrity in all aspects of our business. Our dedicated team of professionals have over 19 years of hands on experience, to provide innovative ideas and suggestions tailored to your projects. Our services are customized to your individual needs, paying close attention to the details of each project that we are involved with. Please feel free to contact us today!

"Nice"

Romel D on February 2023

David's Builders, Inc., is a locally owned and operated company that values honesty and integrity in all aspects of our business. Our dedicated team of professionals have over 19 years of hands on experience, to provide innovative ideas and suggestions tailored to your projects. Our services are customized to your individual needs, paying close attention to the details of each project that we are involved with. Please feel free to contact us today!

"Nice"

Romel D on February 2023


Avatar for CASSINI CONSTRUCTION

CASSINI CONSTRUCTION

5.00(
6
)
Approved Pro

CASSINI CONSTRUCTION

5.00(
6
)
Approved Pro
21 years of experience
Free onsite estimate

What began as a vision in 2011 has since evolved into more than just the standard construction company. We have exceeded far beyond not just our competitors, but the very limits of what construction can endure. At Cassini, our mission is to craft intelligent, elegant, and inspiring environments. Every material we choose, every detail we refine, all guided by a pursuit of permanence delivering beauty and longevity rarely seen today. 5 STARS on YELP AND GOOGLE

"Bathroom/ pavers/ turf / outside fireplace/ and patio cover.."

robert S on April 2025

What began as a vision in 2011 has since evolved into more than just the standard construction company. We have exceeded far beyond not just our competitors, but the very limits of what construction can endure. At Cassini, our mission is to craft intelligent, elegant, and inspiring environments. Every material we choose, every detail we refine, all guided by a pursuit of permanence delivering beauty and longevity rarely seen today. 5 STARS on YELP AND GOOGLE

"Bathroom/ pavers/ turf / outside fireplace/ and patio cover.."

robert S on April 2025


"Overall my experience with this company was great! The work that was done was really really good! Our contractor who assisted us was Jose. We added a living space and master bedroom to our home. The additions done look as if they were part of my house this whole time. Honestly it looks way better than I expected. The only reason I rated the company a 4.5 was because there was always some kind of miscommunication between our contractor and his workers. Don t get me wrong, things were always resolved, Jose was great at that. But my recommendation to is to make sure communication is #1. That way the customer is not confused or left wondering what will happen next. There was an issue with his floor guy though, he was rude and unprofessional. BUT the reason I am mentioning this is not to put down the company but let you know that we expressed concern for this issue and it was resolved professionally by Jose and it never became an issue again. The quality of work was top notch! His workers were all pretty cool guys and we always felt comfortable of who was coming into our home to do the work. I highly recommend this company for your next big project😊👍🏼"

Victoria V on February 2020

Here at Embee & Associates, Inc., we pride ourselves in a job well done. With an eye for detail, we will help your dreams become realities so please contact us today for a fast and friendly service that you will not be disappointed in!!

"Overall my experience with this company was great! The work that was done was really really good! Our contractor who assisted us was Jose. We added a living space and master bedroom to our home. The additions done look as if they were part of my house this whole time. Honestly it looks way better than I expected. The only reason I rated the company a 4.5 was because there was always some kind of miscommunication between our contractor and his workers. Don t get me wrong, things were always resolved, Jose was great at that. But my recommendation to is to make sure communication is #1. That way the customer is not confused or left wondering what will happen next. There was an issue with his floor guy though, he was rude and unprofessional. BUT the reason I am mentioning this is not to put down the company but let you know that we expressed concern for this issue and it was resolved professionally by Jose and it never became an issue again. The quality of work was top notch! His workers were all pretty cool guys and we always felt comfortable of who was coming into our home to do the work. I highly recommend this company for your next big project😊👍🏼"

Victoria V on February 2020


Avatar for A&E General Builders Co

A&E General Builders Co

5.00(
2
)
Approved Pro

A&E General Builders Co

5.00(
2
)
Approved Pro
6 years of experience
Free onsite estimate

We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of General Contractor services that are customizable to each individual project. You will find us to be competitively priced, paying close attention to the details of each and every project that we are involved with. We look forward to building lasting relationships and guarantee your satisfaction!

"Excellent service quick and convenient did not take long at all very honest with work they do 100% recommend "

Nestor G on July 2025

We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of General Contractor services that are customizable to each individual project. You will find us to be competitively priced, paying close attention to the details of each and every project that we are involved with. We look forward to building lasting relationships and guarantee your satisfaction!

"Excellent service quick and convenient did not take long at all very honest with work they do 100% recommend "

Nestor G on July 2025


Nayk Construction Company LLC

New on HomeAdvisorNew on HomeAdvisor
Approved Pro

Nayk Construction Company LLC

New on HomeAdvisorNew on HomeAdvisor
Approved Pro
4 years of experience
Free onsite estimate

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business! Book with us online or feel free to give us a call today! 6 years of exp

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business! Book with us online or feel free to give us a call today! 6 years of exp


Avatar for Laguna Bay Developing

Laguna Bay Developing

4.56(
9
)
Approved Pro

Laguna Bay Developing

4.56(
9
)
Approved Pro
Customers say: Quick response
115 local quotes requested
Emergency services offered

We are a building, architectural design company that strongly believes in adding value with quality remodeling and affordable pricing. We specialize in crafting your dreams. Our owner, David Fidman, has experience since the 1990's in new construction and remodeling of homes. Our enthusiastic and fully licensed and bonded team can exceed your hopes for any project with our personalized service, whether it is constructing your dream home, renovating and upgrading your curb appeal, or remodeling your existing floor plan. As a boutique firm, we optimize personalization by getting to know our customers needs and wants through an attentive project management style. At Laguna Bay Developing, we want this experience to be as an exciting experience as it is rewarding, from the design plans and material selections to the permit approval and construction process, we will be there for every step, we love to see our clients dreams realized!

"I had an excellent experience working with Laguna Bay Developing. From the initial call and quote all the way through to project completion, they were extremely responsive and professional. Their quote was detailed and transparent, making it easy to understand exactly what I was paying for—no surprises or hidden costs. The work itself was completed on schedule and to a high standard. The team was respectful, organized, and clearly took pride in their work. Communication throughout the process was consistent and clear, which gave me confidence every step of the way. I especially appreciated their attention to detail and willingness to answer any questions I had. It’s not easy to find a company that combines fair pricing, reliability, and great workmanship, but they delivered on all fronts. Highly recommended!"

steve r on March 2025

We are a building, architectural design company that strongly believes in adding value with quality remodeling and affordable pricing. We specialize in crafting your dreams. Our owner, David Fidman, has experience since the 1990's in new construction and remodeling of homes. Our enthusiastic and fully licensed and bonded team can exceed your hopes for any project with our personalized service, whether it is constructing your dream home, renovating and upgrading your curb appeal, or remodeling your existing floor plan. As a boutique firm, we optimize personalization by getting to know our customers needs and wants through an attentive project management style. At Laguna Bay Developing, we want this experience to be as an exciting experience as it is rewarding, from the design plans and material selections to the permit approval and construction process, we will be there for every step, we love to see our clients dreams realized!

"I had an excellent experience working with Laguna Bay Developing. From the initial call and quote all the way through to project completion, they were extremely responsive and professional. Their quote was detailed and transparent, making it easy to understand exactly what I was paying for—no surprises or hidden costs. The work itself was completed on schedule and to a high standard. The team was respectful, organized, and clearly took pride in their work. Communication throughout the process was consistent and clear, which gave me confidence every step of the way. I especially appreciated their attention to detail and willingness to answer any questions I had. It’s not easy to find a company that combines fair pricing, reliability, and great workmanship, but they delivered on all fronts. Highly recommended!"

steve r on March 2025


Avatar for ANDREW'S GENERAL CONSTRUCTION INC

ANDREW'S GENERAL CONSTRUCTION INC

5.00(
6
)
Approved Pro

ANDREW'S GENERAL CONSTRUCTION INC

5.00(
6
)
Approved Pro
12 years of experience
Free onsite estimate

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"Cambio de piso de toda la casa Muy buen trabajo 🤗"

Lourdes M on November 2025

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"Cambio de piso de toda la casa Muy buen trabajo 🤗"

Lourdes M on November 2025


Avatar for Calwest Construction

Calwest Construction

4.64(
11
)
Approved Pro

Calwest Construction

4.64(
11
)
Approved Pro
Customers say: Quick response
29 years of experience
Free onsite estimate

I am a general building contractor and my specialties are all types of remodeling and refurbishing, both residential and commercial. This is a trustworthy family business and we are proud of our excellent workmanship. Much of our business is referred by our customers. Our customers become our friends. Contact info: (714) 903-8932 &calwestconstructionoc@gmail.com

"Great professional people and all work done properly and very tidy with respect for the home owner. The whole crew were very nice to get along with."

John P on November 2025

I am a general building contractor and my specialties are all types of remodeling and refurbishing, both residential and commercial. This is a trustworthy family business and we are proud of our excellent workmanship. Much of our business is referred by our customers. Our customers become our friends. Contact info: (714) 903-8932 &calwestconstructionoc@gmail.com

"Great professional people and all work done properly and very tidy with respect for the home owner. The whole crew were very nice to get along with."

John P on November 2025


Avatar for Prime Construction Services, Inc.

Prime Construction Services, Inc.

5.00(
2
)
Approved Pro

Prime Construction Services, Inc.

5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
13 years of experience

We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of general contractor services that are customizable to each individual project. You will find us to be competitively priced, paying close attention to the details of each and every project that we are involved with. We look forward to building lasting relationships and guarantee your satisfaction! ************ VISIT OUR VIRTUAL TOUR ************** https://players.cupix.com/p/BEWLWLeq *************** COPY & PASTE THIS ADDRESS TO YOUR BROWSER

"Andrew Farias was very professional. He was extremely detailed and finished my ADU right within out agreed price. Andrew was always available to answer any questions and was always very responsive to my emails and texts. He kept me well informed at each phase of my project. The quality of his work was top notch and i feel he went above and beyond. My ADU turned out better than i could have imagined and i would absolutely hire him again. I highly recommend Andrew and Prime Construction ."

Kimberly N on March 2022

We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of general contractor services that are customizable to each individual project. You will find us to be competitively priced, paying close attention to the details of each and every project that we are involved with. We look forward to building lasting relationships and guarantee your satisfaction! ************ VISIT OUR VIRTUAL TOUR ************** https://players.cupix.com/p/BEWLWLeq *************** COPY & PASTE THIS ADDRESS TO YOUR BROWSER

"Andrew Farias was very professional. He was extremely detailed and finished my ADU right within out agreed price. Andrew was always available to answer any questions and was always very responsive to my emails and texts. He kept me well informed at each phase of my project. The quality of his work was top notch and i feel he went above and beyond. My ADU turned out better than i could have imagined and i would absolutely hire him again. I highly recommend Andrew and Prime Construction ."

Kimberly N on March 2022

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FAQs for addition to existing structure building service projects in Ontario, CA

You can typically raise your roof by four to eight feet, depending on your home's structure and roof design. The exact amount depends on factors like roof slope and framing support. Raising the roof creates additional interior space, enhances natural light, and increases your home's value. Consult a professional to determine the feasible height increase for your home.

Yes, you need a building permit to raise your roof. Obtaining a building permit ensures your project complies with local building codes and safety regulations. A professional contractor can assist with the permit and inspection process and ensure all legal and safety requirements are met. Your contractor will be familiar with building codes in your area, which can differ between cities or states.

While it's possible to raise a flat roof, it requires extensive structural modifications. Flat roofs lack the attic space and support structures of pitched roofs, so raising them involves significant engineering to ensure safety and durability. This process can be complex and costly, so professional assessment is essential before undertaking a project of this magnitude.

The Ontario, CA homeowners’ guide to addition to existing structure building services

From average costs to expert advice, get all the answers you need to get your job done.