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Find Addition to existing structure builders in Castro Valley

Avatar for UNITED C CONSTRUCTION, INC

UNITED C CONSTRUCTION, INC

5.00(
3
)
•Approved Pro

UNITED C CONSTRUCTION, INC

5.00(
3
)
•Approved Pro
Customers say: Quick response
1 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!

"Updating our home was a dream we have had for years. But finding a good contractor in Bay Area was so difficult, that we almost gave up. We were introduced to United C Construction by our architect(who we also love!) It was exhausting trying to find someone trustworthy and not overpriced. We had luck of working with Osmar which during the project we had clear communication, expectation of setting, professionalism and superior craftsmanship. He walked us through every step of the way, and helped problem solve tough permitting and structural issues in Berkeley!"

Shelby R on September 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!

"Updating our home was a dream we have had for years. But finding a good contractor in Bay Area was so difficult, that we almost gave up. We were introduced to United C Construction by our architect(who we also love!) It was exhausting trying to find someone trustworthy and not overpriced. We had luck of working with Osmar which during the project we had clear communication, expectation of setting, professionalism and superior craftsmanship. He walked us through every step of the way, and helped problem solve tough permitting and structural issues in Berkeley!"

Shelby R on September 2024

Ashbury General Contracting and Engineering

4.50(
2
)
•Approved Pro

Ashbury General Contracting and Engineering

4.50(
2
)
•Approved Pro
Customers say: Terrific value
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
35 years of experience

Mon-Fri 7a-5pm Fully integrated company. All work is done in-house by employees not sub-contractors. 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 forwards to earning your business! Book with us online or feel free to give us a call today!

"Great work for a great price."

Paul H on March 2023

Mon-Fri 7a-5pm Fully integrated company. All work is done in-house by employees not sub-contractors. 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 forwards to earning your business! Book with us online or feel free to give us a call today!

"Great work for a great price."

Paul H on March 2023

Avatar for Hagenbach Construction

Hagenbach Construction

4.75(
16
)
•Approved Pro

Hagenbach Construction

4.75(
16
)
•Approved Pro
Customers say: Quality work
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
11 local quotes requested

Hagenbach Construction is a locally owned and operated company with over 40 years in business with experience in new home construction, room additions, ADU units and Casitas, kitchen and bathroom remodels and all aspects of home remodeling. Let us show you our stress-free, reliable and professional touch for any of your home needs. We're committed to excellence in customer service and professional quality workmanship. Call today to see what expertise can do for the overall value of your project.

"The finished product is nothing short of stunning. They have some incredibly talented craftsmen, and everyone that's been by so far is absolutely speechless! We plan to have them back for future projects. Remodeling is stressful and John & Amy worked diligently to address all concerns in a timely manner. We are very happy with the addition to our home."

Shayna S on August 2023

Hagenbach Construction is a locally owned and operated company with over 40 years in business with experience in new home construction, room additions, ADU units and Casitas, kitchen and bathroom remodels and all aspects of home remodeling. Let us show you our stress-free, reliable and professional touch for any of your home needs. We're committed to excellence in customer service and professional quality workmanship. Call today to see what expertise can do for the overall value of your project.

"The finished product is nothing short of stunning. They have some incredibly talented craftsmen, and everyone that's been by so far is absolutely speechless! We plan to have them back for future projects. Remodeling is stressful and John & Amy worked diligently to address all concerns in a timely manner. We are very happy with the addition to our home."

Shayna S on August 2023

AM GENERAL CONTRACTOR

5.00(
2
)
•Approved Pro

AM GENERAL CONTRACTOR

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

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

"What ever he plans for the project,He compleat that.He is honest and fair.I will refer him to my friends and family."

Mina R on November 2020

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

"What ever he plans for the project,He compleat that.He is honest and fair.I will refer him to my friends and family."

Mina R on November 2020

Avatar for Creekside Pro Construction, Inc.

Creekside Pro Construction, Inc.

5.00(
24
)
•Approved Pro

Creekside Pro Construction, Inc.

5.00(
24
)
•Approved Pro
Customers say: Quick response
Recommended by 91% of Angi customers
Recommended by 91% of HomeAdvisor customers
4 years of experience

We take great pride in our experience, expertise, quality and customer service that we provide to meet the consumers 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 hired them to install new flooring throughout our home, and we were blown away by their expertise and attention to detail. They helped us select the perfect materials for our needs and budget, and their installation work was flawless. Our new floors look fantastic and have completely transformed the look and feel of our home. Thank you, Creekside Pro Construction, for your excellent work!"

Jack J on May 2023

We take great pride in our experience, expertise, quality and customer service that we provide to meet the consumers 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 hired them to install new flooring throughout our home, and we were blown away by their expertise and attention to detail. They helped us select the perfect materials for our needs and budget, and their installation work was flawless. Our new floors look fantastic and have completely transformed the look and feel of our home. Thank you, Creekside Pro Construction, for your excellent work!"

Jack J on May 2023

North Point Construction and Restoration, Inc.

New on HomeAdvisorNew on HomeAdvisor
•Approved Pro

North Point Construction and Restoration, Inc.

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

At North Point Construction and Restoration, Inc., we pride our company on reliability, great communication, integrity, and quality work that customers can believe in. 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 and working with you! 20 years of experience.

At North Point Construction and Restoration, Inc., we pride our company on reliability, great communication, integrity, and quality work that customers can believe in. 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 and working with you! 20 years of experience.

Universal Construction Company

4.71(
7
)
•Approved Pro

Universal Construction Company

4.71(
7
)
•Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
45 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 and home improvement services that are customizable to each individual project. We specialize in additions and bathroom 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!

"He is very good, communicates well, and he is there when he says he will be and very thorough! I liked doing business with him! He explains everything that he will do before he does the job and he listens to my suggestions."

Marilyn B on June 2019

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 and home improvement services that are customizable to each individual project. We specialize in additions and bathroom 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!

"He is very good, communicates well, and he is there when he says he will be and very thorough! I liked doing business with him! He explains everything that he will do before he does the job and he listens to my suggestions."

Marilyn B on June 2019

Avatar for Fixit Construction, Inc.

Fixit Construction, Inc.

3.00(
1
)
•Approved Pro

Fixit Construction, Inc.

3.00(
1
)
•Approved Pro
Customers say: Terrific value
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
11 years of experience

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!

"They were professional and completed the project on time."

Elizabete T on September 2016

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!

"They were professional and completed the project on time."

Elizabete T on September 2016

Avatar for Springs Construction Corporation

Springs Construction Corporation

New on HomeAdvisorNew on HomeAdvisor
•Approved Pro

Springs Construction Corporation

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

Since 1959, Springs Construction has built its reputation on fine craftsmanship, technical expertise and solid project management.We take a proactive, client driven approach to every one of our projects, exceeding our customers vision for their homes. We want you to feel comfortable and safe during the disruption and enjoy your home for years to come.

Since 1959, Springs Construction has built its reputation on fine craftsmanship, technical expertise and solid project management.We take a proactive, client driven approach to every one of our projects, exceeding our customers vision for their homes. We want you to feel comfortable and safe during the disruption and enjoy your home for years to come.

Avatar for Accurate Home Remodeling

Accurate Home Remodeling

5.00(
1
)
•Approved Pro

Accurate Home Remodeling

5.00(
1
)
•Approved Pro
50 local quotes requested

Accurate Home Remodeling services the San Francisco Bay Area. Driven by years of accumulated experience, we’re a fully licensed, bonded, and insured company offering full construction services ranging from kitchen & bathroom remodeling, exteriors, home additions, and much more. Your assigned estimating designer will sit down with you during the complimentary consultation to help you establish an optimal layout and overall vision for the project at hand. Following the consultation, we can create 3D renders to allow you to preview your newly renovated space. Our approach is to work side by side with you to select material at the best locations around the bay area to make your concepts become a reality. Call or 'click' for a FREE estimate today!

Accurate Home Remodeling services the San Francisco Bay Area. Driven by years of accumulated experience, we’re a fully licensed, bonded, and insured company offering full construction services ranging from kitchen & bathroom remodeling, exteriors, home additions, and much more. Your assigned estimating designer will sit down with you during the complimentary consultation to help you establish an optimal layout and overall vision for the project at hand. Following the consultation, we can create 3D renders to allow you to preview your newly renovated space. Our approach is to work side by side with you to select material at the best locations around the bay area to make your concepts become a reality. Call or 'click' for a FREE estimate today!

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

Yes, hidden rooms are legal, as long as they meet all local building regulations. If you sell your house, most states require homeowners to disclose full houseplans, which would include any hidden rooms.

If your secret room is a safe room, it should contain a means of communication aside from a cell phone, such as a shortwave radio. You should also have plenty of drinking water, a portable generator, emergency food supplies, blankets, pillows, flashlights, batteries and a first aid kit.

Any time you update your home’s square footage, you increase its value, but a secret room is a niche feature that doesn't rank high on every buyer’s list of must-haves. Investing your money in remodeling more common living areas like bedrooms, bathrooms, or kitchens will have a higher ROI than adding a secret room. Many secret rooms can act as entertainment spaces (think a game room or wine cellar) or quiet spaces (a library or study), so when building your secret room you may want to consider its versatility for when you’re ready to sell.

The Castro Valley, 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.

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