Ultimate Guide to Building a Second Story Addition in Los Angeles

Home prices have hit an all-time high in Los Angeles and Southern California. This rise has seen many homeowners in Southern California choose to stay put and do home renovations to improve their quality of life at home rather than move. Some homeowners are even adding space to their homes as an alternative to upgrading to a larger home. In this article, we’ll focus on how to add second story in Los Angeles.

Here at GreatBuildz, a free service that personally matches homeowners in Los Angeles, Orange County, Ventura & San Diego with reliable general contractors, we talk to homeowners every day about second story addition Los Angeles projects and costs – here are some key points to know.

Key Takeaways

  • Second-story additions provide a savvy way to increase living space without sacrificing outdoor areas, offering a transformative solution for homeowners.
  • The average cost of a second-story addition in Los Angeles ranges from $350 to $500 per square foot, with estimates affected by various factors like space, labor, and design complexity.
  • Full second-story additions typically take 6 to 9 months, while partial ones may range from 3 to 5 months, considering factors such as weather, permits, and project complexity.
  • Obtaining building permits involves a comprehensive process, including plumbing, electrical, and mechanical permits, with permit approval timelines varying. Adhering to zoning laws, height restrictions, and architectural guidelines is crucial.
  • Engaging experienced architects and engineers is essential for a successful second-story addition, ensuring compliance with zoning laws, addressing structural requirements, and selecting the right second-story addition contractor for a smooth and well-executed project.

Understanding Second-Level Home Additions

Ultimate Guide to Building a Second Story Addition in Los Angeles 1

Second story home additions are a smart and popular way to use your existing home structure to create more living space. With this addition, you won’t have to worry about losing any of your outdoor yard space. You also won’t need to go through the daunting processes of selling, buying a new home, and moving to a new environment.

Second story home additions add a full or partial additional level to your home. Often, they involve removing the roof, building new space, and installing a new roof over it. But in some cases, the builder can expand the upper level out across an existing one-story section, like a porch or flat-roof garage. Whichever way you prefer, it is always a good idea to let an expert second-story builder handle the work. Done right, the addition can completely transform your space into your dream home.

Cost of Adding a Second Story in Los Angeles

The cost of a second-story addition in Los Angeles varies based on a range of factors, including space, labor, layout and design, materials, etc., but on average, it can cost anywhere between $350 and $500 per square foot, with the very high end at $700 per square foot.

$350 per square foot is likely the lowest estimate you’ll get in Southern California, which works out to about $240,000 for a 700-square-foot second-story. But you may spend up to $350,000 or even more depending on the factors mentioned above.

Other cost factors include:

  • Terrain –You’ll pay more for hillside renovations as they are generally more challenging to access.
  • Adding a bathroom, which can range between $30,000 and $50,000
  • Whether or not the existing house is on a slab foundation determines how difficult it will be to run new plumbing.
  • Whether or not you’ll need to upgrade your electrical panel to accommodate new electric needs.
  • Cost of staying in your temporary home during the renovation.
  • Whether or not you’ll need to re-roof the entire home

Every home is unique, so there’s no easy way to know exactly how much the second-story addition would cost. It’s, therefore, a good idea to get estimates from several general contractors to understand how much the project would cost. Have each contractor break down their bid into all the different elements to make it easier to compare the cost of each item of the estimate. You might also want to start by interviewing a few architects to design the second-story addition plans. 

How Long Does Adding Second Story to House Take in Los Angeles?

The duration varies based on foundation work needs, material timing, permitting, weather, and change orders. Location, terrain, and the state of the first floor also weigh in. But overall, a full second-story addition takes anywhere between 6 and 9 months. A partial one may run for 3-5 months.

Remodeling produces lots of dust and noise, so most homeowners prefer moving out during construction. If you’re planning to move out too, find out how long the construction will take. Your second-story contractor should have a rough idea about this. However, if it’s a partial second-story project and the work area can be sealed off, then you might stay in your home.

Regardless of whether you’re moving or staying during the construction process, you need to mentally prepare yourself at the outset that the project will most likely drag on longer than expected. The construction comes with a ton of unknowns that will invariably create delays during the process. If you just assume at the project outset that it will take two months longer than the contractor projects, you won’t be disappointed that the project isn’t done “on schedule.”

Things to Consider When Planning on Adding a Second Story in Los Angeles


Securing a Permit for a Second Story Addition

Most second-story additions involve adding an extra bedroom and bathroom. So, your building permit will include a plumbing, electrical, and mechanical permit. Note that permit approval takes time, and the length varies from city to city. For instance, in the City of Los Angeles, second-story addition permit approval takes up to 12 weeks. But you can pay an expeditor to speed things up. As your architect will know, the second story addition must conform to the Building Energy Efficiency Standards – Title 24, which reduces wasteful and unnecessary energy use in new buildings.

Understanding Zoning Rules

Zoning laws vary from area to area. So, you need to check if the second-story addition aligns with the zoning laws in your neighborhood. Recently, some counties have passed measures to protect against ‘mansionization’ to prevent architectural designs that don’t match those of the original homes in the area. So, it’s always important to be aware of these and other issues like powerline clearance.

If you’re in a Historic Preservation Overlay Zone (HPOZ), know that your proposed remodel will be under scrutiny. Your architect should be well versed in these guidelines and restrictions, assuming they regularly design plans in your area.

Don’t forget to consider height restrictions and whether your proposed changes will block your neighbor’s view. LA has height restrictions for pitched roofs and flat-roofed homes, respectively. Double-check with the local building department to ensure they’ll clear your project so you don’t end up running afoul of some zoning laws.

How to Plan Your Second Story Addition in Los Angeles

Second story addition home

Find an Experienced Engineer/Architect

You need an experienced architect who can integrate your ideas into a plan that’s safe, functional, and will be approved by the LA building department. A professional architect understands structural codes and will work with the general contractor to get the project done right the first time. They will also help you create the right design for you.

Don’t forget about the first floor. If your home is one-story and you want to add a level, a major consideration is where to put the stairs. Your original one-level layout certainly doesn’t have an obvious place to add a stairway.

This is where an architect comes in. They will have to work with you to redesign your first-level floor plan to incorporate a stairway. You may end up losing a bedroom or living area downstairs in order to accommodate a stairway, and you can then replace this space on the second floor.

Some people adding a second story to their home decide it’s a good opportunity to redesign parts of the first-floor layout as well. While the house is in a major remodel, it’s the perfect time to create that redesigned kitchen master bath, etc.

Utilities May Need an Upgrade

Since you’re increasing your home’s square footage, you’ll need to upgrade things like electrical panels and plumbing. The room will also need ventilation, so you may need to upgrade or re-route your HVAC.

Modification of Foundation

Expect to have some foundation modifications during the remodeling. The second story places more stress on the first floor and will almost always need reinforcement. 

Creative Design Tips

When embarking on a second-story addition, creative design choices can transform a functional expansion into a personalized haven. Here are some tips to consider:

  • Start with an imaginative layout that maximizes space and enhances flow. Consider open concepts, strategic room placements, and versatile multifunctional areas to cater to diverse lifestyle needs.
  • Architectural flair extends beyond floor plans—incorporate aesthetically pleasing elements. Skylights, large windows, and glass doors bring abundant natural light, fostering an inviting atmosphere. High ceilings add a sense of grandeur and openness, while unique textures and finishes contribute character.
  • Modern amenities play a pivotal role in design innovation. Integrate smart home technologies seamlessly for convenience and efficiency. Smart thermostats, lighting systems, and security features enhance the home’s functionality and elevate its contemporary appeal.
  • Don’t shy away from blending materials creatively. Mix and match textures, such as combining wood and metal or incorporating contrasting color schemes. This eclectic approach can breathe life into the space, making it visually stimulating.
  • Embrace outdoor connections. Incorporate balconies, terraces, or rooftop spaces for a harmonious blend of indoor and outdoor living. Green roofs or living walls not only enhance aesthetics but also contribute to sustainability.

Finding the Right Company to Work With to Add a Second Floor in Los Angeles

This is perhaps the most important decision you’ll make. Adding a second story in Los Angeles is no handyman project. It requires skills and experience. Therefore, it’s in your best interest to work with a company that has experience taking on projects of this magnitude.

There are over 20,000 licensed general contractors in Los Angeles County, so finding the right fit for you isn’t always easy. Make sure to take the time to interview and find the right pros for you. When you’re getting bids from contractors for your project based on your plans and project checklist, make sure to review and compare estimates carefully. And finally, don’t just go with the cheapest bid; it might cost you more in the long run.  

Take time to read through the company’s reviews and testimonials and analyze its portfolio, reputation, and number of years in business. Ideally, you should take all the steps in the GreatBuildz vetting process in order to ensure you’re hiring the right contractor for you. If you want to remove the challenge and stress of finding and vetting the right contractor for you, the friendly staff at GreatBuildz will match you with reliable, pre-screened pros that fit your project and budget.


When it comes to planning and coordinating a second story addition for your home, you shouldn’t have to go it alone – GreatBuildz can help simplify your contractor search. GreatBuildz is a free service that connects homeowners in Los Angeles, Orange County, Ventura & San Diego with reliable, thoroughly screened general contractors and provides project support from start to finish.


Call now (818.317.3567) to chat with our local team about your next renovation project or visit our website for more information: www.greatbuildz.com

Hi, we're Paul and Jon - Co-Founders of GreatBuildz. We believe everyone deserves to find a great contractor, have a stress-free renovation, and enjoy their beautiful new space. There are so many contractors out there and it's often hard to tell the good from the bad... until it's too late. We started our company to help simplify your contractor search and help you have a stress-free renovation experience. We're always available to help, no matter where you are in the process. Click here to learn more about our story.

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