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Addition to existing structure builders in San Lorenzo

Avatar for Springs Construction Corporation
Springs Construction Corporation
881 Hurlingame Ave
New on HomeAdvisorNew on Angi
Approved Pro
Springs Construction Corporation
881 Hurlingame Ave
New on AngiNew 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.


JJ Builders Inc
14686 Hanover St
New on HomeAdvisorNew on Angi
Approved Pro
JJ Builders Inc
14686 Hanover St
New on AngiNew on HomeAdvisor
Approved Pro
3 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!

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!


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


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 Bay Quality Construction, Inc.
Bay Quality Construction, Inc.
110 Ryan Industrial Ct
4.88(
8
)
Approved Pro
Bay Quality Construction, Inc.
110 Ryan Industrial Ct
4.88(
8
)
Approved Pro
Customers say: Quick response
29 local quotes requested
5 years of experience

Bay Quality 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.

"It is never an easy experience when damage occurs in one's home. Even less fun when it is a rental property and you have tenants there. Our kitchen flooded and after several weeks of demolition, water and asbestos abatement work, we were ready to find a contractor to jump in and put things back together. Diego and his team from Bay Quality has been AMAZING! While it turned out that he was on the lower side of all of the estimates, that was not why we chose him and his company. We chose him because he is a problem solver. Building new vs reconstruction takes a different approach. Of the 3 contractors I spoke with, Diego impressed me with his willingness to find solutions. I got a sense from other reviews that he would work quickly. In less than two weeks, he had the kitchen back together with new cabinets, countertops, flooring and appliances. He was flexible, communicative, prompt and an absolute pleasure to work with. If you're looking for a contractor for your next project,"

Erik J on January 2025

Bay Quality 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.

"It is never an easy experience when damage occurs in one's home. Even less fun when it is a rental property and you have tenants there. Our kitchen flooded and after several weeks of demolition, water and asbestos abatement work, we were ready to find a contractor to jump in and put things back together. Diego and his team from Bay Quality has been AMAZING! While it turned out that he was on the lower side of all of the estimates, that was not why we chose him and his company. We chose him because he is a problem solver. Building new vs reconstruction takes a different approach. Of the 3 contractors I spoke with, Diego impressed me with his willingness to find solutions. I got a sense from other reviews that he would work quickly. In less than two weeks, he had the kitchen back together with new cabinets, countertops, flooring and appliances. He was flexible, communicative, prompt and an absolute pleasure to work with. If you're looking for a contractor for your next project,"

Erik J on January 2025


Avatar for Hagenbach Construction
Hagenbach Construction
2668 Cinnabar Hills Ct
4.75(
16
)
Approved Pro
Hagenbach Construction
2668 Cinnabar Hills Ct
4.75(
16
)
Approved Pro
Customers say: Quality work
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
43 years of experience

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


Neza Construction, Inc.
33514 13th St.
New on HomeAdvisorNew on Angi
Approved Pro
Neza Construction, Inc.
33514 13th St.
New on AngiNew on HomeAdvisor
Approved Pro
5 years of experience

Neza Construction is a locally owned and operated companiw with over 25 years of industry experience. We specialize in framing and additions, but also offer a wide variety of remodeling and home improvement 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 with our clients and guarantee your satisfaction. We are a bilingual company and are happy to serve both our English and Spanish Speaking communities!

Neza Construction is a locally owned and operated companiw with over 25 years of industry experience. We specialize in framing and additions, but also offer a wide variety of remodeling and home improvement 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 with our clients and guarantee your satisfaction. We are a bilingual company and are happy to serve both our English and Spanish Speaking communities!

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

Converting an existing space into a laundry room is more affordable than building a new addition. While new additions start at $5,000, renovating an existing space for laundry use can begin at $1,300. 

Your specific costs will depend on whether plumbing and electrical connections exist nearby, the quality of finishes you select, and whether any structural modifications are needed. Always budget extra for unexpected issues, particularly in older homes where hidden problems might surface during renovation.

The smallest practical size for a new laundry room addition is 35 square feet, which provides enough space for basic appliances and minimal storage. For renovations utilizing existing space, smaller footprints might work with space-saving solutions like stacked appliances. 

A standard-sized laundry room of 60 square feet offers more comfort and functionality, allowing for counter space and storage cabinets. The optimal size depends on your household needs and available space.

Yes, adding a laundry room requires several permits, particularly for new additions. You'll need building permits, plus specific permits for electrical work, plumbing installations, and possibly HVAC modifications. 

Requirements vary significantly by municipality, so consulting with your local building department before starting work is essential. Proceeding without proper permits can result in fines, mandatory removal of completed work, and complications when selling your property.

The timeline for completing a laundry room addition varies based on project complexity, contractor availability, and permit processing times. Factors that can extend the schedule include material delivery delays, weather conditions, and unforeseen structural issues discovered during construction. 

Renovating an existing space often requires less time than building a completely new addition. Working with an experienced contractor who can coordinate various tradespeople efficiently helps keep your project on schedule.

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.
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