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Addition to existing structure builders in Lake Forest

Avatar for IJH Construction, Inc.
IJH Construction, Inc.
110 W Avenida Cordoba
New on HomeAdvisorNew on Angi
Approved Pro
IJH Construction, Inc.
110 W Avenida Cordoba
New on AngiNew on HomeAdvisor
Approved Pro
24 years of experience
Free onsite estimate

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.

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.


Pacific Pipeline
67 Bentwood Ln
New on HomeAdvisorNew on Angi
Approved Pro
Pacific Pipeline
67 Bentwood Ln
New on AngiNew on HomeAdvisor
Approved Pro
17 years of experience
Free onsite estimate

We are 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.

We are 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.


Avatar for Finish Jobs Construction
Finish Jobs Construction
32726 Wesley Street
5.00(
10
)
Approved Pro
Finish Jobs Construction
32726 Wesley Street
5.00(
10
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
20 years of experience

Finish Jobs Construction focuses on customer service and building long-term relationships. We uphold a standard of integrity bound by fairness, honesty, and responsibility in all of our jobs. We are a locally owned and operated business with more than 13 years of experience serving Wildomar and surrounding areas. There is no job too big or too small for our team.

"Awesome experience. I will hire them for all my future projects. You should too, you will not regret it. They saved me a lot of money by repairing items that other companies wanted to replace. A++"

Desmond B on September 2021

Finish Jobs Construction focuses on customer service and building long-term relationships. We uphold a standard of integrity bound by fairness, honesty, and responsibility in all of our jobs. We are a locally owned and operated business with more than 13 years of experience serving Wildomar and surrounding areas. There is no job too big or too small for our team.

"Awesome experience. I will hire them for all my future projects. You should too, you will not regret it. They saved me a lot of money by repairing items that other companies wanted to replace. A++"

Desmond B on September 2021


Avatar for Socal Express Restoration and Construction Inc.
Socal Express Restoration and Construction Inc.
6860 Canby Avenue, Suite 114
New on HomeAdvisorNew on Angi
Approved Pro
Socal Express Restoration and Construction Inc.
6860 Canby Avenue, Suite 114
New on AngiNew 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

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


Avatar for Opulent Design Build
Opulent Design Build
9471 IRVINE CENTER DR, #150
5.00(
10
)
Approved Pro
Opulent Design Build
9471 IRVINE CENTER DR, #150
5.00(
10
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
18 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.

"He does great work and is a great person"

Alex S on March 2019

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.

"He does great work and is a great person"

Alex S on March 2019


Avatar for All Service Industries, Inc.
All Service Industries, Inc.
881 West 18th Street
4.96(
12
)
Approved Pro
All Service Industries, Inc.
881 West 18th Street
4.96(
12
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
38 years of experience

All Service Industries, inc., has been serving the Orange County Coastal Communities in California area for over 27 years! We offer Prompt and Professional Service with Quality Workmanship in which include: remodeling, building, painting, interior and exterior design, custom built homes, and most importantly customer service. We have many happy references available. Call us today to see why we come so highly recommended! You can start by visiting out website www.AllService911.com

"I called All Service out to replace cabinetry below and both sides of my kitchen sink, and to install a new kitchen floor due to a tube that suddenly burst below the kitchen sink. The technician was friendly, professional, outlined the estimate well, and made sure I was happy with the results as the job went along. His team did a great job and I would hire them again."

Terence W on January 2023

All Service Industries, inc., has been serving the Orange County Coastal Communities in California area for over 27 years! We offer Prompt and Professional Service with Quality Workmanship in which include: remodeling, building, painting, interior and exterior design, custom built homes, and most importantly customer service. We have many happy references available. Call us today to see why we come so highly recommended! You can start by visiting out website www.AllService911.com

"I called All Service out to replace cabinetry below and both sides of my kitchen sink, and to install a new kitchen floor due to a tube that suddenly burst below the kitchen sink. The technician was friendly, professional, outlined the estimate well, and made sure I was happy with the results as the job went along. His team did a great job and I would hire them again."

Terence W on January 2023


Avatar for JR Elite Builders
JR Elite Builders
2621 Santa Ysabel Ave
New on HomeAdvisorNew on Angi
Approved Pro
JR Elite Builders
2621 Santa Ysabel Ave
New on AngiNew on HomeAdvisor
Approved Pro
30 years of experience
Free onsite estimate

We are trusted home improvement company dedicated to delivering high-quality remodeling services with precision, reliability, and craftsmanship. Specializing in kitchen and bathroom renovations, full home makeovers, and custom carpentry, we work closely with homeowners to transform their vision into reality. Whether it’s a modern upgrade or a classic restoration, We bring experience, attention to detail, and a commitment to customer satisfaction to every project. Our team prides itself on clear communication, on-time delivery, and results that exceed expectations.

We are trusted home improvement company dedicated to delivering high-quality remodeling services with precision, reliability, and craftsmanship. Specializing in kitchen and bathroom renovations, full home makeovers, and custom carpentry, we work closely with homeowners to transform their vision into reality. Whether it’s a modern upgrade or a classic restoration, We bring experience, attention to detail, and a commitment to customer satisfaction to every project. Our team prides itself on clear communication, on-time delivery, and results that exceed expectations.


Avatar for Prime Construction Services, Inc.
Prime Construction Services, Inc.
865 S. Milliken Ave., Unit A
5.00(
2
)
Approved Pro
Prime Construction Services, Inc.
865 S. Milliken Ave., Unit A
5.00(
2
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor 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


Pro A Line Construction
64 Kazan St
New on HomeAdvisorNew on Angi
Approved Pro
Pro A Line Construction
64 Kazan St
New on AngiNew on HomeAdvisor
Approved Pro
Free onsite estimate
Emergency services offered

With over 30 years of experience, I take pride in my quality craftsmanship. We are owner operated, and believe in building long-term relationships with our clients by delivering honesty along with exceptional work. We pride our company on our close attention to detail to perform the highest quality of work. Give us a call today at 714-612-0448 we look forward to working with you!

With over 30 years of experience, I take pride in my quality craftsmanship. We are owner operated, and believe in building long-term relationships with our clients by delivering honesty along with exceptional work. We pride our company on our close attention to detail to perform the highest quality of work. Give us a call today at 714-612-0448 we look forward to working with you!


Avatar for Tagg Design & Build Inc
Tagg Design & Build Inc
3612 Los Flores Ave
5.00(
3
)
Approved Pro
Tagg Design & Build Inc
3612 Los Flores Ave
5.00(
3
)
Approved Pro
Free onsite estimate

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 the start to the 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.

"Hiring TAGG Design & Build was the right choice. This decision made my workflow efficient and seamless since they offered multiple services in one company. Working with them on both the design and construction process for the addition to my home was easy, fast, and cost friendly. They added a master suite and an additional family/TV room to the existing. The work crew was respectful of the property, and the management team was quick to answer any questions we had through the process. They are my go to."

Arthur A on May 2025

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 the start to the 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.

"Hiring TAGG Design & Build was the right choice. This decision made my workflow efficient and seamless since they offered multiple services in one company. Working with them on both the design and construction process for the addition to my home was easy, fast, and cost friendly. They added a master suite and an additional family/TV room to the existing. The work crew was respectful of the property, and the management team was quick to answer any questions we had through the process. They are my go to."

Arthur A on May 2025

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FAQs for addition to existing structure building service projects in Lake Forest, CA

Yes, you can add a bathroom on a concrete slab, but the crew will need to saw-cut the slab, trench in new supply and drain lines, and then patch the concrete without weakening the foundation. Working with an experienced plumber and concrete pro keeps the structure intact and helps the new bathroom pass inspections.

schedule covers planning, permits, framing, rough-ins, finishes, and punch-list items. 

Larger spaces or extensive plumbing and electrical upgrades can stretch the timeline, while a simple powder-room conversion may wrap up faster. Hiring licensed pros helps keep the schedule on track and the work up to code.

The best location depends on how your family uses the space. An upstairs bath keeps nighttime trips close to the bedrooms, while a first-floor powder room is handy for guests and everyday traffic. 

Think about where plumbing lines already run, how much square footage you can spare, and what layout changes fit your budget. A pro can map out the smartest spot and handle any code hurdles.

With the right planning, you can carve out a bathroom in almost any part of the house. A successful addition requires sufficient space, proper ventilation, and access to plumbing and electrical systems. Structural modifications and adherence to building codes are essential. 

This process demands careful planning and the coordination of specialized professionals who ensure that the new space meets all code requirements and functional needs.

Under specific conditions, adding an extra bedroom can boost home value more than adding a bathroom. Home value is driven by overall configuration, market demand, and functional balance. A new bedroom influences the property’s appeal in different ways, while an additional bathroom enhances living convenience. Evaluating the current layout and market trends determines the optimal choice for maximum value.

The Lake Forest, 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.
master bedroom with fireplace
Jun 26, 2025
Jun 26, 2025
Budget for bedroom remodel costs based on factors such as bedroom size, remodel type, features, materials, labor, and more.
CONTRACTOR LOOKING OVER HOME DEVELOPMENT
Apr 19, 2025
Apr 19, 2025
Budget for your general contractor’s hourly rate by considering factors such as project scope, fee structure, pricing model, and more.
Outdoor view of the modern house
Jun 16, 2025
Jun 16, 2025
Explore how square footage, room type, home additions, and other common factors affect house renovation costs with our detailed cost guide.
BRIGHT OPEN ATTIC SPACE
Jun 10, 2025
Jun 10, 2025
An in-law suite is a great solution for people who have family visiting often. Explore how much an in-law suite costs and prep to build yours.
white and gray kitchen with butchers block countertop
Apr 8, 2025
Apr 8, 2025
Looking to enhance the warmth and utility of your kitchen? Explore how much a butcher block countertop costs and start your budget here.
built-in outdoor kitchen with grill and sink
Apr 30, 2025
Apr 30, 2025
Budget for outdoor kitchen costs based on factors such as appliances, materials, permits, labor, amenities, kitchen size, customizations, and more.
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