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Addition to existing structure builders in Valencia

Avatar for California Designers Remodeling, Inc.
California Designers Remodeling, Inc.
11601 Moorpark Street
5.00(
17
)
Approved Pro
California Designers Remodeling, Inc.
11601 Moorpark Street
5.00(
17
)
Approved Pro
Customers say: Quick response
16 years of experience
Free onsite estimate

xx

"Ray and his team are my go to contractors when I need work done. I have now worked with California Designers Remodeling four times (since 2008) and I am thrilled with the results. I hired them again this year to build out a new kitchen, bath, laundry room/pantry . They created this stunning new addition They also enclosed the carport to give me extra garage space, which has been incredibly useful. All of the workers are professional and courteous."

B M on May 2025

xx

"Ray and his team are my go to contractors when I need work done. I have now worked with California Designers Remodeling four times (since 2008) and I am thrilled with the results. I hired them again this year to build out a new kitchen, bath, laundry room/pantry . They created this stunning new addition They also enclosed the carport to give me extra garage space, which has been incredibly useful. All of the workers are professional and courteous."

B M on May 2025


Avatar for Flip It Homes, Inc.
Flip It Homes, Inc.
20501 Ventura Blvd.
4.97(
16
)
Approved Pro
Flip It Homes, Inc.
20501 Ventura Blvd.
4.97(
16
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
7 years of experience

With 20 years of experience in the construction industry, we are the experts you need to handle your remodeling needs. We handle everything from garage conversions, New ADU'S, kitchens to bathrooms to additions. We are fully licensed and insured with the state of California. We will treat your home or business as we would our own. Give us a call today, we look forward to working with you!

"I am very grateful to Flip it team, especially Roy, for the hard work that they invested in my house renovation. I compared four bids before I chose Flip it. Roy came to my house and explained to me in detail what he planned to do. I was impressed that he had everything in-house: engineers, designers, and the crew that actually worked on my house. I was amazed by the finished project that was near to my house. I also saw another project that Roy did and spoke with his client. After that, I was 100% sure that I wanted to go with Flip it. I really recommend doing business with them. They are professional, reliable, and experienced."

yogev k on January 2024

With 20 years of experience in the construction industry, we are the experts you need to handle your remodeling needs. We handle everything from garage conversions, New ADU'S, kitchens to bathrooms to additions. We are fully licensed and insured with the state of California. We will treat your home or business as we would our own. Give us a call today, we look forward to working with you!

"I am very grateful to Flip it team, especially Roy, for the hard work that they invested in my house renovation. I compared four bids before I chose Flip it. Roy came to my house and explained to me in detail what he planned to do. I was impressed that he had everything in-house: engineers, designers, and the crew that actually worked on my house. I was amazed by the finished project that was near to my house. I also saw another project that Roy did and spoke with his client. After that, I was 100% sure that I wanted to go with Flip it. I really recommend doing business with them. They are professional, reliable, and experienced."

yogev k on January 2024


Avatar for DT Design and Build, Inc.
DT Design and Build, Inc.
15210 Ventura Blvd #208
4.91(
64
)
Approved Pro
DT Design and Build, Inc.
15210 Ventura Blvd #208
4.91(
64
)
Approved Pro
Super Service Award
Customers say: True professional
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
11 years of experience

We at DT Design and Build, Inc., focus on the quality of our projects over quantity. We use our years of experience and expertise to complete your project with perfection. Customer service and honesty are the most important aspects of our business and your satisfaction is always guaranteed. Please call us today for an estimate. We look forward to working with you. Serious inquiries only please. If you have any question please call us at 818-2724213

"Very satisfied with this company. Finished the project in a timely manner. Tal is a great guy. Very caring and did everything possible for me to be happy"

Liana F on November 2024

We at DT Design and Build, Inc., focus on the quality of our projects over quantity. We use our years of experience and expertise to complete your project with perfection. Customer service and honesty are the most important aspects of our business and your satisfaction is always guaranteed. Please call us today for an estimate. We look forward to working with you. Serious inquiries only please. If you have any question please call us at 818-2724213

"Very satisfied with this company. Finished the project in a timely manner. Tal is a great guy. Very caring and did everything possible for me to be happy"

Liana F on November 2024


Avatar for Dreamland DB, Corp.
Dreamland DB, Corp.
19336 Calvert Street
New on HomeAdvisorNew on Angi
Approved Pro
Dreamland DB, Corp.
19336 Calvert Street
New on AngiNew on HomeAdvisor
Approved Pro
4 years of experience
Free onsite estimate

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer’s needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer’s needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.


Avatar for West Side Builder
West Side Builder
3161 Fairfield Ave
5.00(
7
)
Approved Pro
West Side Builder
3161 Fairfield Ave
5.00(
7
)
Approved Pro
Customers say: Quick response
4 years of experience
Free onsite estimate

We are a locally owned and operated company that values honesty, integrity, and will treat your home as if it were our own. We have many years of experience to give you confidence that we are your number one choice for your next home project. You will find us to be competitively priced, while still paying close attention to the details of each and every project that we are involved with. We take pride in building long lasting relationships and look forward to hearing from you!

"They were on time and they did a great job"

Katie G on February 2022

We are a locally owned and operated company that values honesty, integrity, and will treat your home as if it were our own. We have many years of experience to give you confidence that we are your number one choice for your next home project. You will find us to be competitively priced, while still paying close attention to the details of each and every project that we are involved with. We take pride in building long lasting relationships and look forward to hearing from you!

"They were on time and they did a great job"

Katie G on February 2022


Avatar for Green Renovation Group, Inc.
Green Renovation Group, Inc.
15030 Ventura Boulevard Suite 11
4.35(
23
)
Approved Pro
Green Renovation Group, Inc.
15030 Ventura Boulevard Suite 11
4.35(
23
)
Approved Pro
Customers say: Quality work
44 years of experience
Free onsite estimate

Established in 1981. Green Renovation Group Inc. is a licensed general contracting company with over 39 years of experience, which specializes in home remodeling. We are fully licensed and bonded construction company, specializing in utilizing environmentally and economically friendly equipment and techniques to renovate homes. Our priority is to help our customers to create their dream homes in a healthy and efficient way for both their families and the world. Back in 1981, Brad opened the company, and since then we have delivered countless of smiles to our customers. We are committed to completing your project on schedule and within your budget. We take pride in our work, as well as your home, and are dedicated to keeping everything as comfortable and clean as possible throughout each stage of project. Don't hesitate to give us a call at (877) 740-6059 for a FREE estimate and consultation. Call us Today!

"We had a great experience remodeling our bathroom. Sean was very professional to work with. They also helped out with the design of our master bed and bathroom, and we love it! Highly recommend to use them!"

Jose C on May 2023

Established in 1981. Green Renovation Group Inc. is a licensed general contracting company with over 39 years of experience, which specializes in home remodeling. We are fully licensed and bonded construction company, specializing in utilizing environmentally and economically friendly equipment and techniques to renovate homes. Our priority is to help our customers to create their dream homes in a healthy and efficient way for both their families and the world. Back in 1981, Brad opened the company, and since then we have delivered countless of smiles to our customers. We are committed to completing your project on schedule and within your budget. We take pride in our work, as well as your home, and are dedicated to keeping everything as comfortable and clean as possible throughout each stage of project. Don't hesitate to give us a call at (877) 740-6059 for a FREE estimate and consultation. Call us Today!

"We had a great experience remodeling our bathroom. Sean was very professional to work with. They also helped out with the design of our master bed and bathroom, and we love it! Highly recommend to use them!"

Jose C on May 2023


Avatar for Aria Pro Builders
Aria Pro Builders
23823 Via Campana
4.11(
9
)
Approved Pro
Aria Pro Builders
23823 Via Campana
4.11(
9
)
Approved Pro
Customers say: Quick response
6 years of experience
Free onsite estimate

10 years

"Aria Pro Builders is changing the perception of the construction business industry. Nir is an honest, talented, creative General Contractor who runs his business with the highest integrity and care. All of his crew members have been amazing, professional and the highest quality in their trade. Nir completely remodeled 2 bathrooms; eliminating outdated tubs; transforming the space with large modern walk in showers complete with river rock shower floors and tile to ceiling, beautiful floating vanities, all expertly installed to perfection. All new tile floors elevated these bathrooms into Spa Settings! All on time or ahead of schedule! The quality and ease of the bathroom remodels led us to have Aria Pro Builders now fully remodel our kitchen, living room and transform our powder room into a full modern bath. Nir's expertise and amazing staff will guide you effortlessly through any project."

Lori S on January 2023

10 years

"Aria Pro Builders is changing the perception of the construction business industry. Nir is an honest, talented, creative General Contractor who runs his business with the highest integrity and care. All of his crew members have been amazing, professional and the highest quality in their trade. Nir completely remodeled 2 bathrooms; eliminating outdated tubs; transforming the space with large modern walk in showers complete with river rock shower floors and tile to ceiling, beautiful floating vanities, all expertly installed to perfection. All new tile floors elevated these bathrooms into Spa Settings! All on time or ahead of schedule! The quality and ease of the bathroom remodels led us to have Aria Pro Builders now fully remodel our kitchen, living room and transform our powder room into a full modern bath. Nir's expertise and amazing staff will guide you effortlessly through any project."

Lori S on January 2023


Avatar for Tagg Design & Build Inc
Tagg Design & Build Inc
3612 Los Flores Ave
5.00(
3
)
Approved Pro
Tagg Design & Build Inc
3612 Los Flores Ave
5.00(
3
)
Approved Pro
Free onsite estimate

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship and complete customer satisfaction, from the start to the completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.

"Hiring TAGG Design & Build was the right choice. This decision made my workflow efficient and seamless since they offered multiple services in one company. Working with them on both the design and construction process for the addition to my home was easy, fast, and cost friendly. They added a master suite and an additional family/TV room to the existing. The work crew was respectful of the property, and the management team was quick to answer any questions we had through the process. They are my go to."

Arthur A on May 2025

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship and complete customer satisfaction, from the start to the completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.

"Hiring TAGG Design & Build was the right choice. This decision made my workflow efficient and seamless since they offered multiple services in one company. Working with them on both the design and construction process for the addition to my home was easy, fast, and cost friendly. They added a master suite and an additional family/TV room to the existing. The work crew was respectful of the property, and the management team was quick to answer any questions we had through the process. They are my go to."

Arthur A on May 2025


Avatar for Socal Express Restoration and Construction Inc.
Socal Express Restoration and Construction Inc.
6860 Canby Avenue, Suite 114
New on HomeAdvisorNew on Angi
Approved Pro
Socal Express Restoration and Construction Inc.
6860 Canby Avenue, Suite 114
New on AngiNew on HomeAdvisor
Approved Pro
5 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 A & A Construction
A & A Construction
14040 Panay Way, Unit 222
5.00(
21
)
Approved Pro
A & A Construction
14040 Panay Way, Unit 222
5.00(
21
)
Approved Pro
Super Service Award
Customers say: Quick response
44 local quotes requested
5 years of experience

A & A Construction LLC 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.

"A&A construction did an amazing job! Thank you"

Celia f on April 2025

A & A Construction LLC 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.

"A&A construction did an amazing job! Thank you"

Celia f on April 2025

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Addition to existing structure building services FAQs

Most ADU projects require several months from initial planning through final inspection. The timeline includes designing plans, securing permits, site preparation, construction, and finishing work. 

Factors affecting duration include project complexity, contractor availability, weather conditions, and local permitting processes. Planning for potential delays due to material shortages or inspection scheduling is advisable when establishing your project timeline.

Homeowners can access various funding sources for ADU projects. Home equity loans and lines of credit leverage existing property value, while construction loans provide phased funding specifically for building projects. Some areas offer specialized ADU financing programs with favorable terms. 

Personal loans might work for smaller conversions, though they often carry higher interest rates. Your financial situation, credit profile, and project scope will determine which option provides the most advantageous terms.

Adding an ADU often increases your property's assessed value, resulting in higher tax obligations. The specific impact varies by location, as assessment methods and tax rates differ between jurisdictions. Some areas offer temporary exemptions or gradual increases to ease the financial transition. 

For accurate projections, consult your local tax assessor before beginning construction to understand how your specific project will affect future tax bills.

Short-term rental regulations vary dramatically between municipalities. Some jurisdictions permit vacation rentals with minimal restrictions, while others impose occupancy limits, licensing requirements, or outright prohibitions, particularly for ADUs. Many areas require owner occupancy of the primary residence when renting an ADU short-term. 

Research your local ordinances thoroughly before planning rental income, as non-compliance penalties can be substantial.

The ADU construction process frequently encounters obstacles, including complex permitting requirements, unexpected site conditions requiring additional work, contractor scheduling difficulties, and budget management challenges. Many homeowners underestimate the complexity of coordinating multiple specialized trades. 

Additionally, ensuring adequate privacy between the main residence and ADU while maintaining aesthetic cohesion requires careful planning. Thorough preparation and working with experienced professionals can help navigate these common pitfalls.

Identifying qualified ADU contractors requires targeted research. Begin by seeking recommendations from neighbors with completed ADU projects or contacting local builder associations for specialist referrals. Review contractors' portfolios specifically for ADU or small residential projects similar to your vision. 

When interviewing potential candidates, assess their familiarity with local ADU regulations, ask about recent similar projects, and request contact information for past clients with comparable projects.

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.
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