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Find Addition to existing structure builders in San Lorenzo

Universal Construction Company

161 Martin Place
4.71(
7
)
•Approved Pro

Universal Construction Company

161 Martin Place
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.

184 Bowling Green Street
3.00(
1
)
•Approved Pro

Fixit Construction, Inc.

184 Bowling Green Street
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 UNITED C CONSTRUCTION, INC

UNITED C CONSTRUCTION, INC

1900 Powell Street Suite 700
5.00(
3
)
•Approved Pro

UNITED C CONSTRUCTION, INC

1900 Powell Street Suite 700
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

Avatar for Citadel PG

Citadel PG

1721 Broadway St. SW 201
4.60(
5
)
•Approved Pro

Citadel PG

1721 Broadway St. SW 201
4.60(
5
)
•Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
5 years of experience

Citadel PG 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 mindful of our customers' interests and make their concerns the basis of our business. We make sure to develop a lasting relationship so that the next time a project is needed there will be no question on who to call. We look forward to earning your business!

"Update: They came out to take care of some issues, which has not been resolved. It was not so good at the beginning but it got better and the work now looks good!"

MADELINE R on June 2021

Citadel PG 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 mindful of our customers' interests and make their concerns the basis of our business. We make sure to develop a lasting relationship so that the next time a project is needed there will be no question on who to call. We look forward to earning your business!

"Update: They came out to take care of some issues, which has not been resolved. It was not so good at the beginning but it got better and the work now looks good!"

MADELINE R on June 2021

Ashbury General Contracting and Engineering

40 12th Street
4.50(
2
)
•Approved Pro

Ashbury General Contracting and Engineering

40 12th Street
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

AM GENERAL CONTRACTOR

2341 W Ave #133
5.00(
2
)
•Approved Pro

AM GENERAL CONTRACTOR

2341 W Ave #133
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 Springs Construction Corporation

Springs Construction Corporation

881 Hurlingame Ave
New on HomeAdvisorNew on HomeAdvisor
•Approved Pro

Springs Construction Corporation

881 Hurlingame Ave
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 Pacific Bay Construction

Pacific Bay Construction

1990 North California Boulevard, Suite 20
5.00(
6
)
•Approved Pro

Pacific Bay Construction

1990 North California Boulevard, Suite 20
5.00(
6
)
•Approved Pro
12 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!

"I couldn't be more thrilled with my decision to hire Omar for my bathroom remodel. I wish I would have initially hired him for 100% of the job, unfortunately I did not and he ended up needing to clean up the damage someone else did. He squeezed me into his schedule on a weekend to correct the final details the other company dropped the ball on!! He is the only quote I received where I genuinely felt like he wanted me to feel heard and implement my vision and budget with his expertise. He is prompt, responsive, kind, honest, extremely knowledgeable in his trade and passionate about what he does. I can't emphasize enough how much I was dreading this remodel from previous crooked contractors but I am over the moon with how seamless my remodel was with Pacific Bay Construction. I had high expectations and expressed such for this project, I was so satisfied that I even referred him to my parents and he took care of their remodel recently. "

Kim B 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!

"I couldn't be more thrilled with my decision to hire Omar for my bathroom remodel. I wish I would have initially hired him for 100% of the job, unfortunately I did not and he ended up needing to clean up the damage someone else did. He squeezed me into his schedule on a weekend to correct the final details the other company dropped the ball on!! He is the only quote I received where I genuinely felt like he wanted me to feel heard and implement my vision and budget with his expertise. He is prompt, responsive, kind, honest, extremely knowledgeable in his trade and passionate about what he does. I can't emphasize enough how much I was dreading this remodel from previous crooked contractors but I am over the moon with how seamless my remodel was with Pacific Bay Construction. I had high expectations and expressed such for this project, I was so satisfied that I even referred him to my parents and he took care of their remodel recently. "

Kim B on July 2025

OM & K BUILDERS COMPANY

14495 Russo Rd # 1140093
5.00(
1
)
•Approved Pro

OM & K BUILDERS COMPANY

14495 Russo Rd # 1140093
5.00(
1
)
•Approved Pro
Free onsite estimate

OM & K BUILDERS COMPANY is a locally owned and operated company that values honesty and integrity in all aspects of our business. Our dedicated team of professionals have 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!

"We had a great experience with OM&K. They were on time, on budget and worked day and night (and weekends) until the job was done. Great outcome and easy to work with. Definitely recommend. "

david h on September 2025

OM & K BUILDERS COMPANY is a locally owned and operated company that values honesty and integrity in all aspects of our business. Our dedicated team of professionals have 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!

"We had a great experience with OM&K. They were on time, on budget and worked day and night (and weekends) until the job was done. Great outcome and easy to work with. Definitely recommend. "

david h on September 2025

Avatar for On Design & Remodeling INC

On Design & Remodeling INC

1798 Technology Drive Suite 229
4.99(
38
)
•Approved Pro

On Design & Remodeling INC

1798 Technology Drive Suite 229
4.99(
38
)
•Approved Pro
Customers say: Quick response
13 local quotes requested
5 years of experience

With years of experience serving the area, we are your solution for all your Remodeling needs. We take great pride in our extreme professionalism, timeliness and superior customer service on every job. We make sure to develop a lasting relationship so that the next time service is needed there will be no question on who to call. Check out our 5 star reviews from happy customers! Call us today so we can discuss your needs and make a plan that fits your budget. Satisfaction guaranteed!

"I wanted to share my fantastic experience with ON Design & Remodeling during my recent bathroom remodeling project. The results are amazing, and I'm so grateful to Raz and Sofia. The bathroom now feels like a high-end spa, The tiles, fixtures, and overall design are top quality. Can't wait for future projects with ON Design & Remodeling! "

Zander K on May 2025

With years of experience serving the area, we are your solution for all your Remodeling needs. We take great pride in our extreme professionalism, timeliness and superior customer service on every job. We make sure to develop a lasting relationship so that the next time service is needed there will be no question on who to call. Check out our 5 star reviews from happy customers! Call us today so we can discuss your needs and make a plan that fits your budget. Satisfaction guaranteed!

"I wanted to share my fantastic experience with ON Design & Remodeling during my recent bathroom remodeling project. The results are amazing, and I'm so grateful to Raz and Sofia. The bathroom now feels like a high-end spa, The tiles, fixtures, and overall design are top quality. Can't wait for future projects with ON Design & Remodeling! "

Zander K on May 2025

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FAQs for addition to existing structure building service projects in San Lorenzo, 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 San Lorenzo, 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.

See all articles
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