Q: Are hidden rooms legal?

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.

Q: What should be in a safe room?

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.

Q: Does a secret room add value to your home?

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.

Universal Construction Company

Universal Construction Company

Customers say: Quick response

Recommended by 100% of Angi 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

Fixit Construction, Inc.

184 Bowling Green Street

Fixit Construction, Inc.

184 Bowling Green Street

Customers say: Terrific value

Recommended by 100% of Angi 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

UNITED C CONSTRUCTION, INC

1900 Powell Street Suite 700

UNITED C CONSTRUCTION, INC

1900 Powell Street Suite 700

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

Ashbury General Contracting and Engineering

Customers say: Terrific value

Recommended by 100% of Angi 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

Hagenbach Construction

2668 Cinnabar Hills Ct

Hagenbach Construction

2668 Cinnabar Hills Ct

Customers say: Quality work

Recommended by 93% of Angi customers

16 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

AM GENERAL CONTRACTOR

Customers say: Quick response

Recommended by 100% of Angi 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

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.

Walls n Beyond Painting n Remodeling

Walls n Beyond Painting n Remodeling

Customers say: Super punctual

Recommended by 100% of Angi customers

30 local quotes requested

A full-service, state-licensed, bonded, and insured residential and commercial painting company with 15 years of experience serving San Francisco. We specialize in residential and commercial interior painting, wallpaper removal, drywall repair, knockdown texture, comprehensive color consulting, faux finishes, specialty finishes, metal and wood decking, and epoxies. Walls n Beyond Painting Company brings extensive experience and a strong understanding of customer needs and expectations to your residential or commercial painting project. Our top priority as a painting company is customer satisfaction, and we guarantee it.

"The owner, Juan Ortiz bent over backwards to accommodate my schedule, my specs, my wishes. He was patient, professional, friendly and responded immediately when I tried to contact him. His crew was EXCELLENT. The arrived on time, everyday. They fixed things they weren't required to fix. They did a painstakingly beautiful job, and they cleaned up thoroughly. I recommend them enthusiastically and will definitely be using them again."

Maia K on September 2019

A full-service, state-licensed, bonded, and insured residential and commercial painting company with 15 years of experience serving San Francisco. We specialize in residential and commercial interior painting, wallpaper removal, drywall repair, knockdown texture, comprehensive color consulting, faux finishes, specialty finishes, metal and wood decking, and epoxies. Walls n Beyond Painting Company brings extensive experience and a strong understanding of customer needs and expectations to your residential or commercial painting project. Our top priority as a painting company is customer satisfaction, and we guarantee it.

"The owner, Juan Ortiz bent over backwards to accommodate my schedule, my specs, my wishes. He was patient, professional, friendly and responded immediately when I tried to contact him. His crew was EXCELLENT. The arrived on time, everyday. They fixed things they weren't required to fix. They did a painstakingly beautiful job, and they cleaned up thoroughly. I recommend them enthusiastically and will definitely be using them again."

Maia K on September 2019

GAXL GENERAL CONSTRUCTION

20408 SAN MIGUEL AVENUE

GAXL GENERAL CONSTRUCTION

20408 SAN MIGUEL AVENUE

Customers say: Quick response

Recommended by 100% of Angi customers

23 local quotes requested

For the past 10 years GAXL has gained a reputation as a well trusted general construction company in the Bay Area. We depart from the idea that our clients deserve the best remodeling experience. The main focus for us is finishing the work right the first time and on-time, always within budget. At GAXL General Construction we are aiming to be a company leader in the market in Northern California in which our clients can trust with 100% confidence their construction/ remodeling needs. We strive to be consistent as well as efficient in the delivery of our services, and offer our clients a one-stop source for their construction and remodeling needs. Once again, thank you!, we are looking forward to speaking with you about your next project; big or small, we are here for you! How about that new deck or gazebo? Are you ready for those family gatherings? Want to turn your backyard into your new summer/fall hang out spot? We will make sure we bring you creative solutions done perfectly right with the help of our experts. Let's talk today! -Building with Vision.

"We received quotes from 3 different contractors. We chose GAXL because it's close to Newark and I like how Jose explains everything in detail. Originally we thought the remodeling would take 4 weeks but it took close 6 weeks. The whole project was great, the craftsmanship was superb. At one point, we found some tiles that are not very nice (from the manufacturer) and we asked them to redo the bathroom wall. They don't complain and understand our request. The workers are great, especially Marvin and this other guy (forgot his name). They WORK very very hard from 8a to 6p everyday. Jose is on time and is very prompt in returning calls or text. In fact he's the only contractor who's very prompt and I like that! On one of the walls they discovered a mold due to rain leaking and they're able to fix it in 4 days which is great. Jose and his son pickup the materials from the suppliers and drop them in our house. Overall, Jose and his men are courteous. I will definitely use GAXL for future remodeling."

Johann W on February 2025

For the past 10 years GAXL has gained a reputation as a well trusted general construction company in the Bay Area. We depart from the idea that our clients deserve the best remodeling experience. The main focus for us is finishing the work right the first time and on-time, always within budget. At GAXL General Construction we are aiming to be a company leader in the market in Northern California in which our clients can trust with 100% confidence their construction/ remodeling needs. We strive to be consistent as well as efficient in the delivery of our services, and offer our clients a one-stop source for their construction and remodeling needs. Once again, thank you!, we are looking forward to speaking with you about your next project; big or small, we are here for you! How about that new deck or gazebo? Are you ready for those family gatherings? Want to turn your backyard into your new summer/fall hang out spot? We will make sure we bring you creative solutions done perfectly right with the help of our experts. Let's talk today! -Building with Vision.

"We received quotes from 3 different contractors. We chose GAXL because it's close to Newark and I like how Jose explains everything in detail. Originally we thought the remodeling would take 4 weeks but it took close 6 weeks. The whole project was great, the craftsmanship was superb. At one point, we found some tiles that are not very nice (from the manufacturer) and we asked them to redo the bathroom wall. They don't complain and understand our request. The workers are great, especially Marvin and this other guy (forgot his name). They WORK very very hard from 8a to 6p everyday. Jose is on time and is very prompt in returning calls or text. In fact he's the only contractor who's very prompt and I like that! On one of the walls they discovered a mold due to rain leaking and they're able to fix it in 4 days which is great. Jose and his son pickup the materials from the suppliers and drop them in our house. Overall, Jose and his men are courteous. I will definitely use GAXL for future remodeling."

Johann W on February 2025

My Construction Group

My Construction Group

Customers say: Terrific value

Recommended by 97% of Angi customers

211 local quotes requested

We Stand Behind Our Work, Quality, Brand and Commitment Located in San Jose, My Construction Group is your one source for construction needs, and quality design. Our experienced team and project managers will listen and help you focus on your goals, create an innovative design or renovate on matching your vision, and take all the worry and stress out of the process for you. Our team of professional contractors and project managers oversee and manage each project efficiently through on-site preparation, on-time scheduling, accurate budgeting and cost management. In addition, our goal is to assure quality building services while maintaining consistent client communication throughout each project. My Construction Group is a leading home remodeling company, interested in making the best and most remarkable construction in California. Please click or copy the link to see our new construction project https://youtu.be/1teqJZQhzBA

"Our experience is identical to what other reviewers shared. And yes, you should run from this company as fast as you can. Do not buy what Abraham shared that the payment must be made when the inspection is passed. Check the Business and Professions code yourself, the payment only needs to be made when the job is completed. It is very COMMON that the job is not even done or poorly performed even the inspection is passed. Here are the issues that multiple families including us run into with this company:: The project was delayed for over 9 months. No one manages the job. He often employs young men from his own Jewish community. They are enthusiastic but had no prior experience. The worse part is that they don't get paid. Two of them even set up a new construction business knowing Abraham will never pay them. Subcontractors can put your house on lien also. Many reviews you see on Yelp, Google, Angi are NOT genuine. Even the references are fake with hindsight, we were given 2 references. One reference shared the exact same accent as the PM. The other reference was initially happy with their work, but then reached out to us and shared a similar horror story with them like what we experienced. You will lose a lot of $$$ on materials as the subcontractors will somehow leave a thousand dollars worth of quartz at home. Maybe they want to compensate for the money Abraham owed them? Let me tell you, reordering materials is not fun."

Jaqueline R on May 2025

We Stand Behind Our Work, Quality, Brand and Commitment Located in San Jose, My Construction Group is your one source for construction needs, and quality design. Our experienced team and project managers will listen and help you focus on your goals, create an innovative design or renovate on matching your vision, and take all the worry and stress out of the process for you. Our team of professional contractors and project managers oversee and manage each project efficiently through on-site preparation, on-time scheduling, accurate budgeting and cost management. In addition, our goal is to assure quality building services while maintaining consistent client communication throughout each project. My Construction Group is a leading home remodeling company, interested in making the best and most remarkable construction in California. Please click or copy the link to see our new construction project https://youtu.be/1teqJZQhzBA

"Our experience is identical to what other reviewers shared. And yes, you should run from this company as fast as you can. Do not buy what Abraham shared that the payment must be made when the inspection is passed. Check the Business and Professions code yourself, the payment only needs to be made when the job is completed. It is very COMMON that the job is not even done or poorly performed even the inspection is passed. Here are the issues that multiple families including us run into with this company:: The project was delayed for over 9 months. No one manages the job. He often employs young men from his own Jewish community. They are enthusiastic but had no prior experience. The worse part is that they don't get paid. Two of them even set up a new construction business knowing Abraham will never pay them. Subcontractors can put your house on lien also. Many reviews you see on Yelp, Google, Angi are NOT genuine. Even the references are fake with hindsight, we were given 2 references. One reference shared the exact same accent as the PM. The other reference was initially happy with their work, but then reached out to us and shared a similar horror story with them like what we experienced. You will lose a lot of $$$ on materials as the subcontractors will somehow leave a thousand dollars worth of quartz at home. Maybe they want to compensate for the money Abraham owed them? Let me tell you, reordering materials is not fun."

Jaqueline R on May 2025

Get matched with top addition to existing structure builders in San Lorenzo, CA

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Universal Construction Company

Universal Construction Company

Fixit Construction, Inc.

Fixit Construction, Inc.

UNITED C CONSTRUCTION, INC

UNITED C CONSTRUCTION, INC

Ashbury General Contracting and Engineering

Ashbury General Contracting and Engineering

Hagenbach Construction

Hagenbach Construction

AM GENERAL CONTRACTOR

AM GENERAL CONTRACTOR

Springs Construction Corporation

Springs Construction Corporation

Walls n Beyond Painting n Remodeling

Walls n Beyond Painting n Remodeling

GAXL GENERAL CONSTRUCTION

GAXL GENERAL CONSTRUCTION

My Construction Group

My Construction Group

The San Lorenzo, CA homeowners’ guide to addition to existing structure building services

How Much Does a Bus Conversion Cost in 2025?

DIY Kitchen Remodel

Build a Dining Room

Build a Secret Room

Build an A-Frame House

Build a Bar

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Get matched with top addition to existing structure builders in San Lorenzo, CA

Enter your zip and get matched with up to 3 pros

Matching on HomeAdvisor

Find Addition to existing structure builders in San Lorenzo

Universal Construction Company

Universal Construction Company

Fixit Construction, Inc.

Fixit Construction, Inc.

UNITED C CONSTRUCTION, INC

UNITED C CONSTRUCTION, INC

Ashbury General Contracting and Engineering

Ashbury General Contracting and Engineering

Hagenbach Construction

Hagenbach Construction

AM GENERAL CONTRACTOR

AM GENERAL CONTRACTOR

Springs Construction Corporation

Springs Construction Corporation

Walls n Beyond Painting n Remodeling

Walls n Beyond Painting n Remodeling

GAXL GENERAL CONSTRUCTION

GAXL GENERAL CONSTRUCTION

My Construction Group

My Construction Group

The San Lorenzo, CA homeowners’ guide to addition to existing structure building services

How Much Does a Bus Conversion Cost in 2025?

DIY Kitchen Remodel

Build a Dining Room

Build a Secret Room

Build an A-Frame House

Build a Bar

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