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Addition to existing structure builders in Sebastopol

Avatar for Tanoak Construction, LLC
Tanoak Construction, LLC
122 Calistoga Road, Unit 194
3.67(
3
)
Approved Pro
Tanoak Construction, LLC
122 Calistoga Road, Unit 194
3.67(
3
)
Approved Pro
Customers say: Quick response
8 years of experience
Free onsite estimate

I have more than 35 years' of residential, commercial and industrial experience and I pride my company on reliability, great communication, integrity, and quality work. I will do my best to keep you as educated as we can on your particular project. I look forward to earning your business!

"We recently had our bathroom remodeled by Tanoak Construction and we are extremely satisfied with the quality of workmanship. Gant Bowman and Dave Bowman were always available to answer any questions we had and were very transparent throughout the entire process. Finding a local contractor was difficult, but Tanoak Construction made the process easy and stress-free. They were clean, very respectful while in our home, and gave great advice. Every subcontractor they brought in was also great to work with. We highly recommend them to anyone in the Sonoma County area who needs remodeling work done."

Martin B on September 2023

I have more than 35 years' of residential, commercial and industrial experience and I pride my company on reliability, great communication, integrity, and quality work. I will do my best to keep you as educated as we can on your particular project. I look forward to earning your business!

"We recently had our bathroom remodeled by Tanoak Construction and we are extremely satisfied with the quality of workmanship. Gant Bowman and Dave Bowman were always available to answer any questions we had and were very transparent throughout the entire process. Finding a local contractor was difficult, but Tanoak Construction made the process easy and stress-free. They were clean, very respectful while in our home, and gave great advice. Every subcontractor they brought in was also great to work with. We highly recommend them to anyone in the Sonoma County area who needs remodeling work done."

Martin B on September 2023


Avatar for Qualified Builders Construction
Qualified Builders Construction
2206 Oakview Court
5.00(
2
)
Approved Pro
Qualified Builders Construction
2206 Oakview Court
5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
3 years of experience

Customer satisfaction is what determines our success, which is why we take a hands-on approach. When interacting with Qualified Builders Construction, you'll notice that we're particularly focused on the principles of quality workmanship, timely completion, competitive pricing and integrity in all our business dealings. We combine knowledge and research with our extensive practical experience to ensure a specialized approach for your project needs. Contact us today for a fair and accurate estimate of your project. We look forward to adding you to our long and growing list of happy customers.

"Excellent company! Phenomenal work for the price and I am very happy with the fence they built!"

Mark L on January 2023

Customer satisfaction is what determines our success, which is why we take a hands-on approach. When interacting with Qualified Builders Construction, you'll notice that we're particularly focused on the principles of quality workmanship, timely completion, competitive pricing and integrity in all our business dealings. We combine knowledge and research with our extensive practical experience to ensure a specialized approach for your project needs. Contact us today for a fair and accurate estimate of your project. We look forward to adding you to our long and growing list of happy customers.

"Excellent company! Phenomenal work for the price and I am very happy with the fence they built!"

Mark L on January 2023


Reichert Building Solutions
11 Friendly Lane
5.00(
4
)
Approved Pro
Reichert Building Solutions
11 Friendly Lane
5.00(
4
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
9 years of experience

With years of experience serving the area, we are your solution for all your (PWC) 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!

"they are great"

Jenny H on July 2024

With years of experience serving the area, we are your solution for all your (PWC) 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!

"they are great"

Jenny H on July 2024


Avatar for BCR Construction
BCR Construction
889 Jennings Ave
5.00(
1
)
Approved Pro
BCR Construction
889 Jennings Ave
5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
6 years of experience

BCR Construction, 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.

""

Stanley C on March 2022

BCR Construction, 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.

""

Stanley C on March 2022


Concept, Design, Develop, Inc.
PO Box 15035
5.00(
4
)
Approved Pro
Concept, Design, Develop, Inc.
PO Box 15035
5.00(
4
)
Approved Pro
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
10 years of experience

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.

"They did an excellent job! We definitely would want to use them again. They just replaced the siding on the sun beaten part of our house. It looks much better than before and matches the rest of the house perfectly. They were responsive and got things done in a timely manner. I recommend vey highly."

Doug W on May 2024

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.

"They did an excellent job! We definitely would want to use them again. They just replaced the siding on the sun beaten part of our house. It looks much better than before and matches the rest of the house perfectly. They were responsive and got things done in a timely manner. I recommend vey highly."

Doug W on May 2024


Alpha Omega Builders
4485 Hargrave Avenue
4.21(
9
)
Approved Pro
Alpha Omega Builders
4485 Hargrave Avenue
4.21(
9
)
Approved Pro
Customers say: Quality work
20 years of experience
Free onsite estimate

Alpha Omega Builders is your only stop for all of your building needs. We take pride in providing you with the best work available in the area. We treat your home like it was our own.

"On time, knowledgeable, fit us into his schedule. Had a small lingering issue and he came back quickly to fix the problem. A pleasure to work with."

Mary B on September 2017

Alpha Omega Builders is your only stop for all of your building needs. We take pride in providing you with the best work available in the area. We treat your home like it was our own.

"On time, knowledgeable, fit us into his schedule. Had a small lingering issue and he came back quickly to fix the problem. A pleasure to work with."

Mary B on September 2017


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
231 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


Wadleigh Group, Inc.
214 Club Drive
New on HomeAdvisorNew on Angi
Approved Pro
Wadleigh Group, Inc.
214 Club Drive
New on AngiNew on HomeAdvisor
Approved Pro
18 years of experience
Free onsite estimate

Wadleigh Group, 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.

Wadleigh Group, 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.


Advanced Construction Company
4251 Susan Lane
5.00(
3
)
Approved Pro
Advanced Construction Company
4251 Susan Lane
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
34 years of experience

ACC has been providing residential/commercial remodeling services to Northern CA since 1991. We are reliable, provide detailed estimates and competitive pricing. We are a Certified Green Builder. Advanced Construction Company has been in business since 1991, specializing in residential remodels. During the past 30 years, we have taken pride in providing 100% customer satisfaction through honesty, dependability and quality workmanship. Ed Story (owner/president) has more than 35 years of experience in the construction industry. An innovative problem solver, Ed brings experience and creative insight to every job. Experts in making your visions a reality, we use only quality materials and supplies and consistently work with the same subcontractors. Offering competitive fixed bid prices for any kind of work, ACC is the answer to all of your construction and remodeling needs.

"Very professional and easy to work with."

Carol H on July 2016

ACC has been providing residential/commercial remodeling services to Northern CA since 1991. We are reliable, provide detailed estimates and competitive pricing. We are a Certified Green Builder. Advanced Construction Company has been in business since 1991, specializing in residential remodels. During the past 30 years, we have taken pride in providing 100% customer satisfaction through honesty, dependability and quality workmanship. Ed Story (owner/president) has more than 35 years of experience in the construction industry. An innovative problem solver, Ed brings experience and creative insight to every job. Experts in making your visions a reality, we use only quality materials and supplies and consistently work with the same subcontractors. Offering competitive fixed bid prices for any kind of work, ACC is the answer to all of your construction and remodeling needs.

"Very professional and easy to work with."

Carol H on July 2016


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
220 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!

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