How Much Does It Cost To Add 1000 Square Feet to a House In Los Angeles?

Embarking on a home expansion journey, whether minor or significant, demands careful consideration of various factors. In this blog, we delve into the intricacies of adding 1000 square feet to your home in Los Angeles, exploring the costs, design choices, and construction aspects involved. Join us on this informative journey to demystify the complexities of expanding your living space and making informed decisions for your home improvement project.

Here at GreatBuildz, a free service that connects homeowners in Los Angeles, Orange, and Ventura Counties with reliable home contractors, we speak to homeowners every day about the cost breakdown of adding 1,000 square feet to homes – read on to learn more.

Cost to add 1000 SF tablet

What is the Cost to Add 1,000sf to Your Home in Los Angeles?

Expanding a home in Los Angeles by 1000 square feet involves considerable costs, influenced by factors such as room size, type, and location. On average, you can expect a 1,000-square-foot addition to cost between $200,000 and $300,000, equaling around $200-300 per square foot.

The type of room plays a pivotal role in the cost of your addition, with master bedrooms or family rooms generally costing less than kitchens or bathroom additions, where additional plumbing and cabinetry contribute to higher expenses. In Los Angeles, mid-priced bathrooms can range from $22,000 to $30,000, while high-end ones may soar to $55,000-$75,000.

Moreover, the location of the expansion matters; ground-floor additions differ from stand-alone structures and second-story additions. Second-story additions, in particular, can potentially double the budget due to complex demolition, structural concerns, engineering plans, and the potential need for relocation during construction. 

Cost to add 1000 square feet - worker with mobile phone

Major Costs That Go Into Adding 1,000 Square Feet To Your Home

Building a 1,000-square-foot addition involves various major costs that contribute to the overall budget. These include:

  • Construction costs per square foot: Influenced by factors like the complexity of the design, materials chosen, and local labor rates, the average construction cost per square foot can range from $100 to $300
  • Architectural and design fees: covering the creation of plans and blueprints, these typically amount to 10-20% of the total project cost
  • Permits and Fees: Vary based on location and the scope of the project
  • Labor costs: encompass skilled tradespeople, contractors, and possibly subcontractors
  • Material Costs: Constitute a substantial portion of the budget, encompassing everything from framing and roofing to insulation, flooring, and finishing materials. Specialized rooms, like kitchens or bathrooms, incur higher costs due to plumbing, cabinetry, and fixtures
  • Site preparation costs: Including excavation, foundation work, and utility connections
  • Unforeseen expenses: Often estimated at around 10% of the total budget, these account for unexpected issues or changes during construction

Cost to add 1000 SF flooring job

Building Out Versus Up

The decision to build out horizontally or up vertically depends on various factors, each with its own set of considerations and implications. Building out, expanding the footprint of a structure on the same level, often involves less complexity and may be more cost-effective in terms of foundation work and site preparation. It’s a suitable choice when there is ample land available, providing the opportunity for expansive single-story additions.

On the other hand, building up involves adding additional stories or levels to an existing structure. While this maximizes vertical space, it comes with added complexities and costs, such as:

  • Reinforcing the existing foundation
  • Addressing structural concerns
  • Complying with zoning regulations
  • The need for stairs or an elevator
  • Potential disruptions during construction

Building up is often a practical solution when land is limited or when the goal is to preserve outdoor space.

Ultimately, the decision between building out and building up depends on the specific requirements, budget constraints, and aesthetic preferences of the homeowner. A careful assessment of the property, local building codes, and long-term goals is essential in making an informed choice between horizontal and vertical expansion.

Cost to add 1,000 SF professional painter on the roof

Process and Timing of Building a 1000 sf Addition

The process of building a 1000-square-foot addition is influenced by factors like design complexity, permitting, and construction requirements. Initially, homeowners collaborate with architects to create detailed plans, considering the layout, materials, and functionality of the addition. Obtaining necessary permits from local authorities follows, a crucial step that can vary in duration based on the municipality’s regulations and workload.

Once permits are secured, construction can commence, starting with site preparation, foundation work, and framing. The timeline for these stages depends on factors such as weather conditions and the complexity of the design. Subsequently, skilled tradespeople and contractors execute plumbing, electrical, and HVAC installations, followed by insulation, drywall, and finishing work.

The overall timing for building a 1000-square-foot addition typically ranges from a few months to a year or more, contingent on factors like the size of the project, the availability of labor, and any unforeseen challenges. Effective project management is vital to staying on schedule, and homeowners should anticipate potential delays due to weather, supply chain issues, or unexpected construction complexities. 

Which Professionals to Hire When Planning a Major Addition

Cost to add 1000 SF team brainstorm

When planning a 1000 sf home addition, engaging the right professionals is crucial for a successful project. Professionals you might hire include:

    • Architect or residential designer: Essential for conceptualizing and creating plans that align with your vision, ensuring structural integrity and adherence to local building codes. Their expertise helps optimize space and design for functional and aesthetic purposes.
    • Structural engineer: Vital when altering existing structures, providing insights into load-bearing considerations and ensuring safety.
    • General contractors: Oversee the construction process, coordinating subcontractors, managing permits, and ensuring the project aligns with the proposed timeline and budget.
    • Plumbers or electricians: If the addition involves plumbing or electrical work
    • Interior designer: Can contribute to optimizing the space aesthetically.
    • Local building inspector: Engaging one early in the planning phase helps navigate regulatory requirements and ensures compliance with building codes


Collaborating with professionals such as these ensures a comprehensive and well-executed major addition project, minimizing risks and maximizing the functionality and value of the space. GreatBuildz is dedicated to helping homeowners find the perfect partners for their needs.


Just reach out to us to be personally matched with three of our trusted, pre-vetted contractors in the Los Angeles and Southern California areas. Contact GreatBuildz today at 818.317.3567 or visit our website for more information.

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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