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Find Addition to existing structure builders in Simi Valley

Avatar for So Cal Builders & Design Inc
So Cal Builders & Design Inc
4.6(
294
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved (Corporate)

Super Service Award Winner

In business since 1982

Free estimates

Warranties offered

"Our initial meeting with Suj was great. Initially, we had in mind a much larger job. He had quoted us $3000 for the closet demolition / wall rebuild (non-load bearing), packaged with several other items. Together with the fee for drawings ($4000) and permits, this was a bit higher than we anticipated. However, we decided to go with Suj due to his responsiveness and professionalism. Out of our other quotes, Suj’s pricing was middle of the pack - not the cheapest or most expensive. When the drawings were complete and evaluated, he gave us an updated cost of $6000 over text message. The scope of work had changed, and this was no longer part of a bigger project - understandable. The issue was when he gave us the official estimate a week later and up’d the price once again to $9000. When asked what happened, his exact words were “well, I need to get paid too”. He had weeks to consider before quoting the $6000 and nothing had changed since then. The extra $3000 may be insignificant compared to most renovation costs, but for us in our first home, this was back breaking. We continued with Suj since we were already locked in and well past the 3 day cancellation period. Their work for the most part was exceptional. The new wall blended perfectly into our existing structure, and the ceiling patch was also well done. The problem here was the floor. They had dug up a 1” deep pit in the floor, likely to remove the wall studs. However, they did not patch the floor or even let us know this was going to be an issue. We were never told about the pit until I decided to check in on their progress one day towards the end of the wall build. This required us to pay a handyman to come in next day on a weekend to patch the concrete since we had cabinets being installed the following Tuesday. Suj was aware of this and did not believe it pertinent information. Overall, Suj and SoCal Builders do quality work, but the issues in pricing consistency lost us before the work even started. Not even telling us that we’d be left with a 1” deep pit in our floor after was another huge issue which should’ve been brought up much earlier. This was our first experience with a contractor and I’m not sure if this is typical or not. However, it’s enough to make me doubt I’d contact them for any future work."
Completely renovating both the guest and master bathrooms. In the master bathroom, we're installing a spacious walk-in shower featuring dual black-finished shower heads, elegant floating benches, and marble wall tiles. Meanwhile, the guest bathroom will have a sleek built-in tub and stylish hexagon tiles.
This project involved adding a new master bathroom to the existing house. The shower features sleek white subway tiles complemented by striking black fixtures and shower door hardware. The bathroom floor is adorned with elegant white marble tiles, providing a seamless and luxurious finish. A white shaker vanity topped with a white marble countertop completes the space, creating a clean and sophisticated look.
Experience a whole new level of indoor-outdoor living with the Torres Residence Backyard Remodel. This project highlights the addition of a kitchen sliding door, seamlessly merging your interior and exterior spaces
We remodeled the current kitchen, incorporating the addition of a new sliding door to establish a seamless indoor-outdoor living area
New pool with Baja bench and spa. New pavers, aluminum patio cover and built-in BBQ in the backyard

+563

36 neighbors recently requested a quote
Recommended by86%of homeowners
Avatar for Construction Masters
Construction Masters
4.7(
316
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved

Super Service Award Winner

In business since 1988

Free estimates

Emergency services offered

"I needed a new house built on a complex foundation. Construction Masters did an amazing job from start to finish. Mickey and Moshe listened to everything I was looking for and worked with my vision to turn it into a reality. Their attention to sight lines and details are excellent. Mickey took me through all the work of choosing lights, cabinets, fixtures, etc. The two of them work so well together! Mickey and Moshe were there every day of the week to provide oversight on the project. The philosophy of the company is one of excellence and honesty. I do not know this because it is on a website or brochure; I know it because I had the pleasure of being their client. If they create anything, from a stair banister to a luxury bath or a whole house, it will be done to the highest standards. The work they did building the whole house was so superb that when they finished, I asked to be their client again without considering any other builders. I am going to build an ADU on the other side of my property and it will be built by Construction Masters."
Our Assorted Work
Our Assorted Work
Our Assorted Work
Our Assorted Work
Our Assorted Work

+51

Response time8 hrs
1 neighbors recently requested a quote
Recommended by94%of homeowners
Avatar for HA My Design, Inc.
HA My Design, Inc.
5.0(
378
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved

Super Service Award Winner

In business since 2011

Free estimates

Customers say: True professional

"I recently worked with HA My Design to build an ADU, and I could not be happier with the results. Golan and his crew were always on time and worked hard to ensure the project was completed within budget. The quality of their work was excellent, and they were quick and efficient. I highly recommend HA My Design for anyone looking to build an ADU. Their one-stop-shop showroom, covering 5000 square feet, made selecting finishes a breeze. I will definitely refer them to friends and family!"
After
Kitchen Remodel+Fireplace
Complete Home Renovation
Complete Kitchen Remodel
Complete Kitchen Remodel

+526

Response time1 day
Response rate100%
4 neighbors recently requested a quote
Avatar for Trig Builders, Inc.
Trig Builders, Inc.
4.9(
37
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved

In business since 2004

Free estimates

Warranties offered

"We needed to do a kitchen remodel for a while now so we did a massive research online and by asking friends and family in our area. After meeting with all of them and explaining to them what are we looking for, what we want to do and mainly what is our budget. We received estimates from all the contractors that we met and we selected Trig Builders because Yossi was the most competitively priced and the referrals that we got on him and his company were very positive. Yossi and the workers were very easy people to work and to deal with and Yossi designed the kitchen exactly the way we wanted it with some nice additions of things that we didn’t think we will get. His suggestions about the new kitchen layout, where and what materials to buy were very helpful. Also, his advises and recommendation on where to buy the cabinets, lightings, plumbing and appliances saved us a lot of money. The end result of the new kitchen was perfect and one of the things that added a huge plus before we hired them was the warranty that included in the price of the work that they did."
Addition in Diamond Bar
Addition in Diamond Bar
Addition in Diamond Bar
Addition in Diamond Bar
Addition in Diamond Bar

+15

Response time7 hrs
Recommended by87%of homeowners
Avatar for Imperial Remodeling Inc
Imperial Remodeling Inc
4.6(
127
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved

Super Service Award Winner

In business since 2006

Free estimates

Emergency services offered

"I did not fully know this about me, but I am the client from H***. However, Mr Gino and everyone at imperial remodeling went above and beyond any expectations I could have had. And I am a perfectionist; which does not exist, but no one could have gotten closer than these guys. We did a complete remodel of three bathrooms floors, walls paint etc. I’ve had custom glass installed. And they built out a whole new bathroom for me without destroying the design and functionality of my beautiful mid-century modern home. I am definitely going to work with them again. I hope they work with me( Please read first sentence again). You will not find better quality and affordability in the same place as I did. Thank you imperial remodeling for treating my home as it was your own and for caring about us and exceeding all our expectations. You are the best at home remodel and I am glad we met!"
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+185

Response time1 day
2 neighbors recently requested a quote
Recommended by90%of homeowners
Avatar for R Design, Inc.
R Design, Inc.
4.3(
31
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved

In business since 2007

Free estimates

Small jobs welcome

"I'm a true believer that people crosses your path for a reason. Ramy and his wonderful team provided the best experience with working with a construction team anyone can ask for. Like others who can relate, I had an awful experience with a past remodeling project that traumatized me for life. It was hard for me to trust just anyone! Ramy took that all away. He was confident, easy to talk to, provided reassurance, and professionalism in every way. He would say, I'm with you until the end! I never thought I would have the kitchen of my dreams and he brought it to life plus more. He was with me every step of the way even on unexpected hiccups that comes with renovation. Not to mention he answered my call or text anytime of the day to provide me updates or answer my questions. His goal was to make sure I was happy with the outcome! Now, I have to pinch myself every day to see if it's really true. I look at my beautiful kitchen and can not stop smiling! Not only did it bring joy to me but my entire family! Thank you! Thank You! Thank You Ramy! I'm grateful for you and your entire team! You are all the sweetest! If you are looking for someone you can trust please don't hesitate, you're in safe hands with R Design! Mari-Len Norwalk, CA"
 Joining dining room to kitche
 Cabinets, granite counter, marble/granite floor
 Bath tub wall tiling
 Restaurant previous counter
 Marble

+193

Response time1 day
Response rate99%
8 neighbors recently requested a quote
Avatar for Home Renew 360
Home Renew 360
4.7(
78
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved (Corporate)

In business since 2010

Free estimates

Warranties offered

"We had Home Renew 360 do some major remodeling in our home. We had our kitchen, floors, and bathroom remodelled. The team did a great job. All of the team members were friendly, knowledgeable, and well prepared. We could not be happier with the team that worked on our home. ALL of them! They were clean and did excellent workmanship. They showed up on time and completed the work before the scheduled completion date. Farid was our project manager and he was excellent. He was prepared and provided us excellent service. He responded quickly to our questions, provided quality guidance, and was knowledgable to what was being done to our home and provided excellent creativity when asked about specifics of how our ideas would fit with our remodel. I would high recommend Home Renew 360 for any of your home improvement needs."
Roof in Huntington Beach
Asphalt Shingle Roof
Flat roof
Master Bathroom
Exterior Paint

+179

Response time8 hrs
Response rate100%
35 neighbors recently requested a quote
Avatar for YB Builders Group Inc.
YB Builders Group Inc.
5.0(
11
)
Addition to Existing Structure - Build

Serving Simi Valley, CA and surrounding areas

Approved

In business since 2025

Free estimates

Credit card accepted

"We recently had our kitchen remodeled, and the entire experience exceeded our expectations. From the initial consultation to the final installation, the team was professional, punctual, and paid incredible attention to every detail. They kept the work area clean, communicated with us throughout the project, and delivered exactly what they promised."
Bathroom Remodel
Master bathroom
Master bathroom
Master bedroom
Kitchen Remodel

+74

74 neighbors recently requested a quote
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FAQs for addition to existing structure building service projects in Simi Valley, CA

You can typically raise your roof by four to eight feet, depending on your home's structure and roof design. The exact amount depends on factors like roof slope and framing support. Raising the roof creates additional interior space, enhances natural light, and increases your home's value. Consult a professional to determine the feasible height increase for your home.

Yes, you need a building permit to raise your roof. Obtaining a building permit ensures your project complies with local building codes and safety regulations. A professional contractor can assist with the permit and inspection process and ensure all legal and safety requirements are met. Your contractor will be familiar with building codes in your area, which can differ between cities or states.

While it's possible to raise a flat roof, it requires extensive structural modifications. Flat roofs lack the attic space and support structures of pitched roofs, so raising them involves significant engineering to ensure safety and durability. This process can be complex and costly, so professional assessment is essential before undertaking a project of this magnitude.

The Simi Valley, 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.