Top-rated addition to existing structure builders.

Get matched with top addition to existing structure builders in your area

Enter your zip and get matched with up to 3 pros

Matching on HomeAdvisor

Share some details icon
Share some details about your home project.
Match with local pros icon
Within moments, match with highly-rated local pros.
Compare quotes icon
Compare quotes and choose the best pro for the job.

Addition to existing structure builders in Fairfield

Avatar for Grid Design Build
Grid Design Build
1500 3rd St, Suite A
New on HomeAdvisorNew on Angi
Approved Pro
Grid Design Build
1500 3rd St, Suite A
New on AngiNew on HomeAdvisor
Approved Pro
3 years of experience
Free onsite estimate

We’re 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 Home Improvement services that are customizable to each individual project. We specialize in Additions and Kitchen Remodels, but also offer a wide range of expertise for a variety of other projects. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!

We’re 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 Home Improvement services that are customizable to each individual project. We specialize in Additions and Kitchen Remodels, but also offer a wide range of expertise for a variety of other projects. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!


Cerletti & Kennedy Design-Build
2950 Buskirk Avenue, Suite 300
4.60(
82
)
Approved Pro
Cerletti & Kennedy Design-Build
2950 Buskirk Avenue, Suite 300
4.60(
82
)
Approved Pro
Super Service Award
Customers say: True professional
48 local quotes requested
38 years of experience

SPECIALIZING IN HAPPY CUSTOMERS! Cerletti & Kennedy Design-Build is a full service contractor, family owned and operated for three generations. We specialize in room additions, kitchens and all your remodeling needs. We offer comprehensive design services utilizing the latest 3D CAD technology so you can see your design choices before you build. We're prompt and cost effective, our workers are clean and courteous and our customers are satisfied and happy.

"The job got finished overall I was happy with the finish project. The job was not as smooth I had hoped for. I believe my experience on construction and expectation's might have been out of touch. I would for sure let them bid on more work for me if I ever planned to do any more construction."

Larry P on April 2025

SPECIALIZING IN HAPPY CUSTOMERS! Cerletti & Kennedy Design-Build is a full service contractor, family owned and operated for three generations. We specialize in room additions, kitchens and all your remodeling needs. We offer comprehensive design services utilizing the latest 3D CAD technology so you can see your design choices before you build. We're prompt and cost effective, our workers are clean and courteous and our customers are satisfied and happy.

"The job got finished overall I was happy with the finish project. The job was not as smooth I had hoped for. I believe my experience on construction and expectation's might have been out of touch. I would for sure let them bid on more work for me if I ever planned to do any more construction."

Larry P on April 2025


Avatar for JP Winchell Construction, Inc.
JP Winchell Construction, Inc.
10 Softwind Drive
5.00(
2
)
Approved Pro
JP Winchell Construction, Inc.
10 Softwind Drive
5.00(
2
)
Approved Pro
Customers say: Quick response
14 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!

"JP Winchell Construction has done an amazing job with my bathroom remodel. They were very attentive to my needs, and worked with me on design choices every step of the way. If you want your project done right the first time, I would choose this company over others I have used in the past. Thank you for all your hard work and dedication to detail!"

Elaine _ on December 2024

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!

"JP Winchell Construction has done an amazing job with my bathroom remodel. They were very attentive to my needs, and worked with me on design choices every step of the way. If you want your project done right the first time, I would choose this company over others I have used in the past. Thank you for all your hard work and dedication to detail!"

Elaine _ on December 2024


Avatar for McCormick Home Builders, Inc.
McCormick Home Builders, Inc.
23445 Haynes Street
4.25(
18
)
Approved Pro
McCormick Home Builders, Inc.
23445 Haynes Street
4.25(
18
)
Approved Pro
Customers say: True professional
235 local quotes requested
8 years of experience

MCCORMICK HOME BUILDERS INC We’re a locally owned and operated company that values honesty and integrity and treats your home or business as if it were our own. We are experts in all aspects of roofing projects and our services are customizable to each individual project. We specialize in both installations and replacements. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!

"We recently remodeled our bathroom with McCormick, and it was a fantastic experience. Khaled was informative, patient, and genuinely helpful, guiding us through choices for a perfect design. The team’s professionalism showed in their punctuality and quality. Every aspect was done with care, from tile placement to lighting. The transformation is truly impressive; the bathroom now feels open and luxurious. We’re beyond pleased with the result and look forward to more projects with them."

Geoffrey C H on January 2025

MCCORMICK HOME BUILDERS INC We’re a locally owned and operated company that values honesty and integrity and treats your home or business as if it were our own. We are experts in all aspects of roofing projects and our services are customizable to each individual project. We specialize in both installations and replacements. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!

"We recently remodeled our bathroom with McCormick, and it was a fantastic experience. Khaled was informative, patient, and genuinely helpful, guiding us through choices for a perfect design. The team’s professionalism showed in their punctuality and quality. Every aspect was done with care, from tile placement to lighting. The transformation is truly impressive; the bathroom now feels open and luxurious. We’re beyond pleased with the result and look forward to more projects with them."

Geoffrey C H on January 2025


Avatar for Red Line Remodeling & Design, LLC
Red Line Remodeling & Design, LLC
870 Hillside Terrace
4.86(
7
)
Approved Pro
Red Line Remodeling & Design, LLC
870 Hillside Terrace
4.86(
7
)
Approved Pro
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
33 local quotes requested

Red Line Remodeling & Design, LLC is the premier home improvement and remodeling company centrally located in Rio Vista serving Solano County, Sacramento County, San Joaquin, and Contra Costa County in California. We have over 20 years experience, family owned and operated. Our #1 goal as a company is having complete customer satisfaction and there is no job that is too big or too small. We specialize in a variety of projects Specializing in custom kitchen and bathroom remodeling, open concept and room additions. If you want the job done right, call us today for a free estimate.

"Extremely satisfied. I hired them for my kitchen remodel and then again for our bathroom remodel! High quality work! Friendly and easy to work with!! Will be using them again for our next project!"

Teresa U on April 2022

Red Line Remodeling & Design, LLC is the premier home improvement and remodeling company centrally located in Rio Vista serving Solano County, Sacramento County, San Joaquin, and Contra Costa County in California. We have over 20 years experience, family owned and operated. Our #1 goal as a company is having complete customer satisfaction and there is no job that is too big or too small. We specialize in a variety of projects Specializing in custom kitchen and bathroom remodeling, open concept and room additions. If you want the job done right, call us today for a free estimate.

"Extremely satisfied. I hired them for my kitchen remodel and then again for our bathroom remodel! High quality work! Friendly and easy to work with!! Will be using them again for our next project!"

Teresa U on April 2022


Avatar for Prosper Construction Development, Inc.
Prosper Construction Development, Inc.
180 Steuart St., Box 194631
4.88(
38
)
Approved Pro
Prosper Construction Development, Inc.
180 Steuart St., Box 194631
4.88(
38
)
Approved Pro
Customers say: Quick response
Recommended by 97% of Angi customers
Recommended by 97% of HomeAdvisor customers
246 local quotes requested

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 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!

"Fast response and clear communication throughout the process."

Marco T on April 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 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!

"Fast response and clear communication throughout the process."

Marco T on April 2025


Robert McCollister Construction Inc
1512 D St
5.00(
3
)
Approved Pro
Robert McCollister Construction Inc
1512 D St
5.00(
3
)
Approved Pro
Customers say: Quick response
11 local quotes requested
15 years of experience

Robert McCollister Construction, Inc is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business.

"Robert is a veteran to the contracting business. He is a “salt of the earth” gentleman with an incredible skill set that he utilized to bring our vision to reality. This was a very intricate build, taking a 1940’s cottage and doubling its size while updating absolutely everything. His subcontractors are top notch which matches Robert’s impeccable work ethic. We are absolutely thrilled with the results. "

Patrick Celiberti T on February 2025

Robert McCollister Construction, Inc is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business.

"Robert is a veteran to the contracting business. He is a “salt of the earth” gentleman with an incredible skill set that he utilized to bring our vision to reality. This was a very intricate build, taking a 1940’s cottage and doubling its size while updating absolutely everything. His subcontractors are top notch which matches Robert’s impeccable work ethic. We are absolutely thrilled with the results. "

Patrick Celiberti T on February 2025


Patton Construction
P O Box 5336
4.75(
16
)
Approved Pro
Patton Construction
P O Box 5336
4.75(
16
)
Approved Pro
Customers say: Quick response
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
43 years of experience

At Patton Construction, our company is based on the belief that our customers' needs are of the utmost importance. Our team is committed to meeting those needs. We welcome the opportunity to earn your trust and deliver you the best service. No job is too big or too small for our experienced team. Call today for a quote.

"Cal Patton is THE ABSOLUTE BEST. The work he did remodeling my garage into a studio apartment was done with quality workmanship, professional care, and great communication. Now, two years later, I am adding a bathroom and had some questions. Cal answered my texts and calls immediately and, even though he had several other projects going on, he literally jumped in the car and came to advise another contractor to set him straight. (I wish Cal could be doing the bathroom addition but he was booked currently.) I highly recommend Cal. He's got your back, he is a true pro, and a great human being."

Taylor K on December 2022

At Patton Construction, our company is based on the belief that our customers' needs are of the utmost importance. Our team is committed to meeting those needs. We welcome the opportunity to earn your trust and deliver you the best service. No job is too big or too small for our experienced team. Call today for a quote.

"Cal Patton is THE ABSOLUTE BEST. The work he did remodeling my garage into a studio apartment was done with quality workmanship, professional care, and great communication. Now, two years later, I am adding a bathroom and had some questions. Cal answered my texts and calls immediately and, even though he had several other projects going on, he literally jumped in the car and came to advise another contractor to set him straight. (I wish Cal could be doing the bathroom addition but he was booked currently.) I highly recommend Cal. He's got your back, he is a true pro, and a great human being."

Taylor K on December 2022


RSF Construction Inc.
6910 Monte Verde Drive
New on HomeAdvisorNew on Angi
Approved Pro
RSF Construction Inc.
6910 Monte Verde Drive
New on AngiNew on HomeAdvisor
Approved Pro
224 local quotes requested
6 years of experience

RSF Construction Inc. is a leader in providing our customers with the highest quality service in an honest, efficient, and professional way. Our pledge is to create successful relationships with our customers, employees and community by building trust, treating every project with the utmost integrity and exceeding expectations. We look forward to working with you!

RSF Construction Inc. is a leader in providing our customers with the highest quality service in an honest, efficient, and professional way. Our pledge is to create successful relationships with our customers, employees and community by building trust, treating every project with the utmost integrity and exceeding expectations. We look forward to working with you!


ABC Construction
847 Malibu Dr
5.00(
1
)
Approved Pro
ABC Construction
847 Malibu Dr
5.00(
1
)
Approved Pro
22 years of experience
Free onsite estimate

We invite you to experience a tradition of customer satisfaction that will exceed your greatest expectations. Our professionalism and quality workmanship will accurately reflect your taste and lifestyle. From conception to completion, we work with you until the job is done. We are ethical, honest, and easy to communicate with. Call us today you'll be pleased you did. Thank you

"I hired this contractor for a major plumbing job, including fixing a slab leak, concrete replacement, and installing new hot and cold water piping. The work was completed promptly and with excellent results. The contractor's professionalism, engineering background, and clear communication were truly impressive. Highly recommended!"

Sergey G on February 2025

We invite you to experience a tradition of customer satisfaction that will exceed your greatest expectations. Our professionalism and quality workmanship will accurately reflect your taste and lifestyle. From conception to completion, we work with you until the job is done. We are ethical, honest, and easy to communicate with. Call us today you'll be pleased you did. Thank you

"I hired this contractor for a major plumbing job, including fixing a slab leak, concrete replacement, and installing new hot and cold water piping. The work was completed promptly and with excellent results. The contractor's professionalism, engineering background, and clear communication were truly impressive. Highly recommended!"

Sergey G on February 2025

...
Showing 1-10 of 865

Addition to existing structure building services FAQs

How far you can push a room depends on the structure you choose. A cantilevered bump-out can extend 24 inches before building codes require its own footing or foundation. Anything longer needs engineered support and a permit. Check local codes or consult with a structural professional before finalizing plans to ensure your design remains safe and compliant.

Most bump-outs are completed within one to four weeks, even with minimal electrical, plumbing, or HVAC work. Their compact size means less demolition, simpler inspections, and fewer weather-related delays compared to a full-scale addition. Your contractor can provide a more precise timeline once they have determined the scope, materials, and permit schedule, but plan on having the extra square footage ready in approximately a month.

The 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.
built-in outdoor kitchen with grill and sink
Apr 30, 2025
Apr 30, 2025
Budget for outdoor kitchen costs based on factors such as appliances, materials, permits, labor, amenities, kitchen size, customizations, and more.
BLUE TWO STORY HOME
Apr 30, 2025
Apr 30, 2025
Budget for the cost to add a second story based on factors such as size, foundation work, materials, labor, permits, post-construction cleaning, and more.
small bathroom that has been updated in a remodel
Apr 29, 2025
Apr 29, 2025
Budget for the cost to remodel a small bathroom based on factors such as required fixtures, bathroom size, labor, remodel type, site prep, and more.
guest house in the backyard
Apr 27, 2025
Apr 27, 2025
Need to build a guest house? Here’s how much it costs, what factors affect cost, and what to expect.
Kitchen view leading into dining area
Apr 28, 2025
Apr 28, 2025
Use this guide to budget for bump-out addition costs based on factors such as room size, room type, labor, finishes, permits, and more.
House roof with nice window
Apr 28, 2025
Apr 28, 2025
Budget for dormer addition costs based on factors such as roof type, framing, customizations, reinforcement, cladding, labor, and more.
Share project details to get started.