When your family outgrows your home, you face a choice: move or improve. For Los Angeles homeowners who love their neighborhood, their schools, and their community, a home addition is the smartest way to gain the space you need without giving up the location you love. A well-planned addition can deliver a 50 to 70 percent return on investment while giving you the extra square footage your family needs right now.
At ACE Design & Build, we specialize in designing and constructing home additions that look and feel as though they were part of the original architecture. Whether you need a ground-floor family room extension, a second-story master suite, a sunroom, or an expanded garage, our team handles every aspect - from structural engineering and architectural design through permitting, construction, and finish work.
Building an addition in Los Angeles presents unique challenges. Hillside lots, seismic requirements, setback restrictions, and the need to match existing rooflines and exterior finishes all demand a contractor with deep local experience. Our structural engineers and project managers have navigated these complexities on hundreds of projects, ensuring your addition meets all code requirements while integrating flawlessly with your home.
We take a design-build approach that eliminates the costly gaps between architects and builders. Your project begins with a thorough evaluation of your home's existing structure, foundation capacity, and zoning allowances. From there, our designers create plans that maximize functionality, natural light, and flow - while our estimators deliver a transparent, line-item proposal that protects your budget from start to finish.
What's Included
In-home consultation and feasibility assessment
Architectural design with 3D renderings
Structural engineering and seismic calculations
Full permit processing and city inspections
Foundation and footing work
Framing, roofing, and exterior finish matching
Electrical, plumbing, and HVAC extensions
Insulation, drywall, and interior finishes
Flooring, trim, paint, and hardware
Dedicated project manager and warranty coverage
Why Choose ACE for Home Additions
Seamless Architectural Integration
Our designers study your home's existing style, materials, and proportions to ensure the addition looks original - not like an afterthought. From matching rooflines and siding to blending interior finishes, every detail is considered so the new space feels like it has always been part of your home.
Structural Expertise for LA Conditions
Los Angeles construction demands rigorous seismic engineering and compliance with some of the strictest building codes in the country. Our in-house engineers design additions that are structurally sound, code-compliant, and built to protect your family for decades.
Strong Return on Investment
Home additions in Los Angeles typically deliver a 50 to 70 percent return on investment. With median home prices among the highest in the nation, adding quality square footage is one of the most financially sound improvements you can make.
Our Home Additions Process
Free in-home consultation to assess your existing structure, discuss your needs, and evaluate zoning and setback allowances.
Custom architectural plans and structural engineering designed to integrate seamlessly with your home, delivered with a detailed line-item proposal.
We secure all necessary building permits and schedule inspections with the local building department.
Construction begins with foundation work and progresses through framing, mechanical systems, and finishes - managed by your dedicated project manager.
Final inspection, walkthrough, and handover with full warranty documentation.
Frequently Asked Questions About Home Additions
Home additions in Los Angeles typically cost between $300 and $600 per square foot depending on the complexity of the project, foundation requirements, and finish level. A 400-square-foot addition might range from $120,000 to $240,000. We provide a detailed, transparent proposal before any work begins.
The construction phase typically takes three to six months, depending on the size and scope of the addition. Including design and permitting, the total timeline from initial consultation to completion is usually five to nine months.
Yes. All structural additions in Los Angeles require building permits and inspections. Our team manages the entire permitting process, including plan submissions, plan check revisions, and scheduling all required inspections.
In most cases, yes. Second-story additions require a thorough evaluation of your existing foundation and structure to determine if reinforcement is needed. Our structural engineers assess your home and design the most efficient and cost-effective approach.
Absolutely. Our design team specializes in creating additions that integrate with your home's existing architectural style, rooflines, exterior materials, and interior finishes. The goal is always to make the addition look like it was part of the original design.
Yes, in most cases. Additions are typically built adjacent to or above existing living areas, and we take careful steps to maintain a safe, clean separation between the construction zone and your occupied space.
What Our Clients Say
“ACE added a 400 sq ft primary suite to our home - bedroom, walk-in closet, and spa bathroom. You cannot tell where the original house ends and the addition begins. The roof lines, stucco texture, and trim all match perfectly.”
“We needed a home office and a playroom but did not want to move. ACE built a beautiful two-room addition off the back of our house in just ten weeks. The vaulted ceiling they suggested makes it feel twice the size.”
“Our second-story addition was a complex project - structural engineering, new staircase, HVAC extension. ACE coordinated everything seamlessly. Our new upstairs master retreat has views of the hills that make us smile every morning.”
“ACE added a sunroom and expanded our living area by 300 sq ft. The bi-fold glass doors that open to the garden were their suggestion and completely transformed how we use the space.”
“We added a bedroom and bathroom above our garage for our teenage son. ACE handled the structural reinforcement, soundproofing, and private entrance. It is like he has his own apartment. Best investment for family harmony.”