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.

McGee Construction

McGee Construction

Customers say: True professional

Recommended by 94% of Angi customers

32 local quotes requested

McGee Construction is a family-owned and operated remodeling company with over 30 years of experience. We specialize in major renovations, including kitchens, bathrooms, room additions, and ADUs. Our team is dedicated to delivering high-quality craftsmanship and personalized service, and we personally stand behind the success of every project. Call now to discuss your next project!

"David Burch and his crew remodeled our den with live edge shelves and built in cabinets. The level of professionalism from all of the tradesmen was top notch. I love our den. Working with mcgee construction was so easy and pleasant. David would respond in a timely manner and explained everything in depth. I highly recommend this company and will definitely be using them for all my remodeling needs."

Jamie A on March 2024

McGee Construction is a family-owned and operated remodeling company with over 30 years of experience. We specialize in major renovations, including kitchens, bathrooms, room additions, and ADUs. Our team is dedicated to delivering high-quality craftsmanship and personalized service, and we personally stand behind the success of every project. Call now to discuss your next project!

"David Burch and his crew remodeled our den with live edge shelves and built in cabinets. The level of professionalism from all of the tradesmen was top notch. I love our den. Working with mcgee construction was so easy and pleasant. David would respond in a timely manner and explained everything in depth. I highly recommend this company and will definitely be using them for all my remodeling needs."

Jamie A on March 2024

Elias Amparano Remodeling

Elias Amparano Remodeling

Customers say: Quick response

Recommended by 100% of Angi customers

10 years of experience

Licensed Contractor, we are a small company but deliver big results, let us give you a quality project for less. We offer 12 month 0 % financing OAC. We accept all major credit cards. We also handle all insurance loss claims with our own in house adjuster. Call us before or after a lose and let us get you what you deserve, before you say yes, let us give you a second opinion we have acquired our customers thousands of dollars more on their claims.

"Easy to work with, fantastic results. The finish on our saltillo tile floors had badly deteriorated and they were able to ressurect it. And their price was quite reasonable."

Ric W on November 2023

Licensed Contractor, we are a small company but deliver big results, let us give you a quality project for less. We offer 12 month 0 % financing OAC. We accept all major credit cards. We also handle all insurance loss claims with our own in house adjuster. Call us before or after a lose and let us get you what you deserve, before you say yes, let us give you a second opinion we have acquired our customers thousands of dollars more on their claims.

"Easy to work with, fantastic results. The finish on our saltillo tile floors had badly deteriorated and they were able to ressurect it. And their price was quite reasonable."

Ric W on November 2023

Olalde Group, Inc.

741 East Adams Park Drive

Olalde Group, Inc.

741 East Adams Park Drive

Customers say: Quick response

6 years of experience

Free onsite estimate

Olalde Group, 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 makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business. Please give us a call today!

"David and Efrain did an amazing job converting our oversized 2 car garage into a one bedroom apartment. They were very attentive, cost conscious and efficient! They were on hand monitoring the subcontractors and making sure the job was done correctly. They did a great job and we are very gratefully for their hard work!"

Darlene J on October 2025

Olalde Group, 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 makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business. Please give us a call today!

"David and Efrain did an amazing job converting our oversized 2 car garage into a one bedroom apartment. They were very attentive, cost conscious and efficient! They were on hand monitoring the subcontractors and making sure the job was done correctly. They did a great job and we are very gratefully for their hard work!"

Darlene J on October 2025

RET Construction Corp

RET Construction Corp

Customers say: Quality work

Recommended by 95% of Angi customers

21 years of experience

With several years experience, we work hard to bring each customer the best possible service and quality available. We look forward to working with you on your next project. We welcome your questions and thank you for your interest.

"Kevin brought our dream ADU to life! He is an amazing contractor who pays great attention to detail and he has several licenses which insured his work was of the highest quality. He REALLY listens to what the customer wants and he delivers! We are SO pleased with our new ADU and we offer him our highest recommendation!"

gabriella p on September 2022

With several years experience, we work hard to bring each customer the best possible service and quality available. We look forward to working with you on your next project. We welcome your questions and thank you for your interest.

"Kevin brought our dream ADU to life! He is an amazing contractor who pays great attention to detail and he has several licenses which insured his work was of the highest quality. He REALLY listens to what the customer wants and he delivers! We are SO pleased with our new ADU and we offer him our highest recommendation!"

gabriella p on September 2022

Socal Express Restoration and Construction Inc.

6860 Canby Avenue, Suite 114

New on HomeAdvisorNew on HomeAdvisor

•Approved Pro

Socal Express Restoration and Construction Inc.

6860 Canby Avenue, Suite 114

New on HomeAdvisorNew on HomeAdvisor

•Approved Pro

5 years of experience

Free onsite estimate

We are an ethical, honest and professional company. We are easy to communicate with. Always working with you until the job is done right and to your specifications. When working with our company you can expect integrity, prompt service and superior customer service. Always leaving the job site clean . We take pride in our services and enjoy making clients repeat clients. You can count on us to get the job done right the first time. We will meet with you at your convenience and will not keep you waiting. Call us today for your free estimate. You'll be pleased you did. Thank you

OC Home Builders, Inc.

OC Home Builders, Inc.

Customers say: Quick response

Recommended by 94% of Angi customers

48 local quotes requested

OC HOME BUILDERS, INC. is a FAMILY-owned business, working to achieve excellence since 2004. We service all of Orange County. Our goal is that you LOVE the End Result! Please call or TEXT for your FREE estimate (714) 330-9031. We look forward to BUILDING something Beautiful together! Jim is an EXPERT BUILDER & a MASTER at his craft! America is a skilled communicator. Assuring that clients know what to expect next & that each project is held to the highest standards. We are fully licensed, bonded and insured! Our crew is dedicated to building quality construction, including FULL HOME RENOVATIONS, ROOM ADDITIONS, ADU’S, KITCHEN REMODELS, BATHROOM REMODELS, WINDOW & DOOR REPLACEMENTS, GARAGE CONVERSIONS & MORE! We are proud recipients of the “Angi Super Service Award" since 2012, along with other prestigious awards. Meeting & exceeding client expectations for 25 years and counting! We LOVE what we do, and we hope it shows in the end results! CALL or TEXT us for a FREE ESTIMATE (714) 330-9031 Let’s build something beautiful together! CSLB# 1035464

"I will always hire Oc home builders. I have been using them for years. Great attention to detail that sets them apart from others."

maelin h on April 2025

OC HOME BUILDERS, INC. is a FAMILY-owned business, working to achieve excellence since 2004. We service all of Orange County. Our goal is that you LOVE the End Result! Please call or TEXT for your FREE estimate (714) 330-9031. We look forward to BUILDING something Beautiful together! Jim is an EXPERT BUILDER & a MASTER at his craft! America is a skilled communicator. Assuring that clients know what to expect next & that each project is held to the highest standards. We are fully licensed, bonded and insured! Our crew is dedicated to building quality construction, including FULL HOME RENOVATIONS, ROOM ADDITIONS, ADU’S, KITCHEN REMODELS, BATHROOM REMODELS, WINDOW & DOOR REPLACEMENTS, GARAGE CONVERSIONS & MORE! We are proud recipients of the “Angi Super Service Award" since 2012, along with other prestigious awards. Meeting & exceeding client expectations for 25 years and counting! We LOVE what we do, and we hope it shows in the end results! CALL or TEXT us for a FREE ESTIMATE (714) 330-9031 Let’s build something beautiful together! CSLB# 1035464

"I will always hire Oc home builders. I have been using them for years. Great attention to detail that sets them apart from others."

maelin h on April 2025

Lira Construction Group

Lira Construction Group

3 years of experience

Free onsite estimate

Lira Construction Group is dedicated to providing our customers with the best quality and craftsmanship. We are here to build relationships with our customers and communities and to provide our employees with a great place to work. We look forward to working with you!

"Patrick and he's team are the best in town! They came in did the framing work as he described, passed all inspections with no problem! He really knows what he is doing and I 100% recommended him!"

Cesar V on February 2025

Lira Construction Group is dedicated to providing our customers with the best quality and craftsmanship. We are here to build relationships with our customers and communities and to provide our employees with a great place to work. We look forward to working with you!

"Patrick and he's team are the best in town! They came in did the framing work as he described, passed all inspections with no problem! He really knows what he is doing and I 100% recommended him!"

Cesar V on February 2025

Newland Construction, Inc.

Newland Construction, Inc.

Customers say: Terrific value

Recommended by 93% of Angi customers

43 years of experience

At Newland Construction Inc. we do room additions, second story additions, interior remodels, kitchens, bathrooms and patios. We are family operated since 1982, and our work speaks for itself. You will not be disappointed; we do large or small projects. We also specialize in building new custom homes, and complete remodels. Call us at (714) 981-5729 Newland Construction, Inc., today!

"My husband and I had several appointments with different contractors. When we met with Terry, we both felt he was very knowledgeable in all areas, and had very good pricing. Needless to say, we chose Newland Construction. From day one, we felt comfortable and at ease. Renovation Project: 1. Moved the small kitchen to our large dining room. 2. Moved dining room to former kitchen ( swapped rooms) 3. Dining room: (former kitchen) removed wall for open concept 4. New flooring 5. Stairs: replaced carpet with laminate, replaced rails 6. Living room: Added a window seat with storage 7. Living room: Added entertainment wall with shelving 8. Living room: Added modern fireplace 9. Added windows, moved sliding glass door WE LOVE THE FINISHED PRODUCT!! The project was right on schedule (5 months) and we didn't go over budget. As it is expected to run into a few snags during ANY renovation, Terry and John were very responsive and quick to resolve any issue. They were on top of the problem, and resolved with excellent results. We get a ton of compliments on our home. Thank you, Terry, John and your crew. You've exceeded our expectations. Highly recommended!!"

Donna A on June 2023

At Newland Construction Inc. we do room additions, second story additions, interior remodels, kitchens, bathrooms and patios. We are family operated since 1982, and our work speaks for itself. You will not be disappointed; we do large or small projects. We also specialize in building new custom homes, and complete remodels. Call us at (714) 981-5729 Newland Construction, Inc., today!

"My husband and I had several appointments with different contractors. When we met with Terry, we both felt he was very knowledgeable in all areas, and had very good pricing. Needless to say, we chose Newland Construction. From day one, we felt comfortable and at ease. Renovation Project: 1. Moved the small kitchen to our large dining room. 2. Moved dining room to former kitchen ( swapped rooms) 3. Dining room: (former kitchen) removed wall for open concept 4. New flooring 5. Stairs: replaced carpet with laminate, replaced rails 6. Living room: Added a window seat with storage 7. Living room: Added entertainment wall with shelving 8. Living room: Added modern fireplace 9. Added windows, moved sliding glass door WE LOVE THE FINISHED PRODUCT!! The project was right on schedule (5 months) and we didn't go over budget. As it is expected to run into a few snags during ANY renovation, Terry and John were very responsive and quick to resolve any issue. They were on top of the problem, and resolved with excellent results. We get a ton of compliments on our home. Thank you, Terry, John and your crew. You've exceeded our expectations. Highly recommended!!"

Donna A on June 2023

Opulent Design Build

9471 IRVINE CENTER DR, #150

Opulent Design Build

9471 IRVINE CENTER DR, #150

Customers say: Quick response

Recommended by 95% of Angi customers

12 local quotes requested

Opulent Design Build . One point of contact from Start to Finish. Opulent Design Build takes the complicated process of home designing, building and remodeling and makes it an experience that you will love! There's no need to fear the design & construction process. Opulent Design Build personally handles every aspect of the construction process: design, engineering, site survey, permitting, construction and inspections. We are truly a "one-stop" design-build company.

"My wife and I were looking into adding some square footage to our home as well as remodel. We were going in circles trying to plan and budget and it honestly was one of the most stressful/hardest experiences of our marriage. That was until we stumbled upon Opulent. I do not remember how we found them, but man, I am so glad we did. Eddie and his whole team were OUTSTANDING throughout the whole process. They really made us feel like we were part of the Opulent Family as well as producing real results. They managed EVERYTHING just about perfectly. From dealing with the permit process to helping us figure out what we needed to fill our space with beautiful fixtures to actually getting the construction done. The preconstruction process was so simple thanks to their amazing team and construction flowed so smoothly. The field workers were respectful and clean every day. 10/10 cannot recommend enough. Thank you Opulent!!"

Shaun M on August 2025

Opulent Design Build . One point of contact from Start to Finish. Opulent Design Build takes the complicated process of home designing, building and remodeling and makes it an experience that you will love! There's no need to fear the design & construction process. Opulent Design Build personally handles every aspect of the construction process: design, engineering, site survey, permitting, construction and inspections. We are truly a "one-stop" design-build company.

"My wife and I were looking into adding some square footage to our home as well as remodel. We were going in circles trying to plan and budget and it honestly was one of the most stressful/hardest experiences of our marriage. That was until we stumbled upon Opulent. I do not remember how we found them, but man, I am so glad we did. Eddie and his whole team were OUTSTANDING throughout the whole process. They really made us feel like we were part of the Opulent Family as well as producing real results. They managed EVERYTHING just about perfectly. From dealing with the permit process to helping us figure out what we needed to fill our space with beautiful fixtures to actually getting the construction done. The preconstruction process was so simple thanks to their amazing team and construction flowed so smoothly. The field workers were respectful and clean every day. 10/10 cannot recommend enough. Thank you Opulent!!"

Shaun M on August 2025

Prime Construction Services, Inc.

865 S. Milliken Ave., Unit A

Prime Construction Services, Inc.

865 S. Milliken Ave., Unit A

Customers say: Quick response

Recommended by 100% of Angi customers

12 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 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! ************ VISIT OUR VIRTUAL TOUR ************** https://players.cupix.com/p/BEWLWLeq *************** COPY & PASTE THIS ADDRESS TO YOUR BROWSER

"Andrew Farias was very professional. He was extremely detailed and finished my ADU right within out agreed price. Andrew was always available to answer any questions and was always very responsive to my emails and texts. He kept me well informed at each phase of my project. The quality of his work was top notch and i feel he went above and beyond. My ADU turned out better than i could have imagined and i would absolutely hire him again. I highly recommend Andrew and Prime Construction ."

Kimberly N on March 2022

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! ************ VISIT OUR VIRTUAL TOUR ************** https://players.cupix.com/p/BEWLWLeq *************** COPY & PASTE THIS ADDRESS TO YOUR BROWSER

"Andrew Farias was very professional. He was extremely detailed and finished my ADU right within out agreed price. Andrew was always available to answer any questions and was always very responsive to my emails and texts. He kept me well informed at each phase of my project. The quality of his work was top notch and i feel he went above and beyond. My ADU turned out better than i could have imagined and i would absolutely hire him again. I highly recommend Andrew and Prime Construction ."

Kimberly N on March 2022

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McGee Construction

McGee Construction

Elias Amparano Remodeling

Elias Amparano Remodeling

Olalde Group, Inc.

Olalde Group, Inc.

RET Construction Corp

RET Construction Corp

Socal Express Restoration and Construction Inc.

Socal Express Restoration and Construction Inc.

OC Home Builders, Inc.

OC Home Builders, Inc.

Lira Construction Group

Lira Construction Group

Newland Construction, Inc.

Newland Construction, Inc.

Opulent Design Build

Opulent Design Build

Prime Construction Services, Inc.

Prime Construction Services, Inc.

The Costa Mesa, 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 Costa Mesa, CA

Enter your zip and get matched with up to 3 pros

Matching on HomeAdvisor

Find Addition to existing structure builders in Costa Mesa

McGee Construction

McGee Construction

Elias Amparano Remodeling

Elias Amparano Remodeling

Olalde Group, Inc.

Olalde Group, Inc.

RET Construction Corp

RET Construction Corp

Socal Express Restoration and Construction Inc.

Socal Express Restoration and Construction Inc.

OC Home Builders, Inc.

OC Home Builders, Inc.

Lira Construction Group

Lira Construction Group

Newland Construction, Inc.

Newland Construction, Inc.

Opulent Design Build

Opulent Design Build

Prime Construction Services, Inc.

Prime Construction Services, Inc.

The Costa Mesa, 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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