Your Local Home Addition Experts
Expand Your Living Space with Expert Home & Room Additions
Professional home addition services throughout California. From second story additions to master suite extensions, we design and build beautiful, functional spaces that enhance your lifestyle and increase your property value.
Design and Engineering Services Throughout California
California Registered Civil Engineer
Projects Completed
Permit Approval Rate
Professional Team Members
At Cecilia Home, we believe in providing clear and transparent architectural services that you can trust. Our experienced engineers and designers are committed to offering personalized solutions, whether you're dealing with complex home additions, seeking assistance with ADU designs, or managing residential remodeling projects. We simplify the architectural process, making it easy to understand and navigate.
Our team ensures that every client receives the most effective architectural strategies, all while building long-term relationships focused on achieving the best possible outcomes. With our California registered civil engineers and a 95% permit approval rate, we have successfully completed over 2,000 projects throughout California with exceptional results and unparalleled customer satisfaction.
Why Choose Cecilia Home For Your Addition
Discover what sets our home addition services apart in California. With our integrated design-build approach, expert team, and client-focused process, Cecilia Home delivers superior results while making your home expansion journey smooth and stress-free.
ONE-STOP DESIGN & BUILD SOLUTION
From concept to completion, our in-house team handles every aspect of your home addition. With integrated architectural design, structural engineering, and construction services, we streamline the entire process and eliminate coordination headaches.
AWARD-WINNING ARCHITECTURAL DESIGN
Our architects create stunning, functional additions that enhance both aesthetics and value. We specialize in seamless integration with existing structures, ensuring your addition looks like it was always part of your home.
STRUCTURAL ENGINEERING EXPERTISE
Our licensed structural engineers specialize in California building conditions, ensuring your addition is built to last. We conduct thorough assessments and develop precise reinforcement plans that guarantee structural integrity and safety.
EXPEDITED PERMIT PROCESSING
With over 15 years of experience navigating California's complex permitting systems, we secure approvals in record time. Our relationships with local building departments and comprehensive documentation preparation minimize delays in your project timeline.
TRANSPARENT FIXED-PRICE CONTRACTS
Enjoy peace of mind with our detailed, fixed-price contracts. We provide comprehensive cost breakdowns and guarantee no surprise charges, allowing you to budget confidently for your home addition investment.
DEDICATED PROJECT MANAGEMENT
Your personal project manager oversees every detail from design through construction. With regular updates, quality control inspections, and responsive communication, we ensure your addition is completed on time and exceeds expectations.
Our Home Addition Services
Expand your living space with professional home addition services throughout California. Our architectural and structural expertise ensures beautiful, functional results for any addition project.
Second Story Additions
Double your living space
Maximize your home with expert vertical expansions that preserve architectural integrity. Our engineers design second-story additions that blend seamlessly with your existing home while doubling your living space.
Luxury Master Suite Extensions
Create your dream retreat
Transform your home with a custom master suite featuring walk-in closets, spa-inspired bathrooms, and private outdoor access—all perfectly integrated with your existing architecture.
Modern Kitchen Expansions
Heart of your home
Create the gathering space your family deserves with our kitchen expansions featuring open layouts, high-end appliances, custom cabinetry, and seamless transitions to dining and outdoor areas.
In-Law Suite Additions
Multigenerational living solutions
Design comfortable spaces for extended family with separate entrances, kitchenettes, accessible bathrooms, and thoughtful amenities while maintaining connection to the main home.
Ready to transform your home? Our design team will create your perfect addition.
Our Process
Our process is designed to be transparent and efficient, delivering a complete one-stop service from design to final permit approval.
1
Free Consultation
Expert advice on your project needs, budget considerations, and permit requirements.
2
On-Site Assessment
Precise measurements and site evaluation for accurate project planning.
3
Design Development
Creating detailed plans and visualizations to bring your vision alive.
4
Permit Acquisition
Navigating complex approval processes to ensure code-compliant construction.
5
Construction Support
Ongoing guidance and contractor coordination throughout the building process.
Featured Home Addition Projects
Explore our portfolio of stunning home addition projects throughout California. Each project showcases our architectural design expertise, engineering precision, and commitment to creating beautiful, functional spaces that perfectly complement existing homes.
Frequently Asked Questions
Answers to common questions about home additions, second story expansions, room extensions, costs, and timelines in California.
Loved By Homeowners
Don't just take our word for it. Here's what our satisfied clients have to say about their experience working with us.
Cecilia Home transformed our single-story home with a beautifully designed second floor addition. Mason personally oversaw the architectural planning, creating a seamless design that looks like it was always part of our home. Their home addition specialists ensured everything was structurally sound while maximizing our budget. The new space has completely changed how our family lives!
Sophia Chen
San Francisco, CA
We hired Cecilia Home to design and build a master suite addition, and they exceeded all expectations. Mason's architectural vision created a space that perfectly balanced luxury with practicality. Their home addition team managed every aspect from foundation to finishing touches with remarkable precision. Our new master bedroom and bathroom have added significant value to our property.
Michael Rodriguez
Palo Alto, CA
The kitchen and family room addition Mason designed for our California home completely transformed our living space. Cecilia Home's team seamlessly integrated the new construction with our existing house, creating an open, light-filled area that's now our favorite gathering place. Their expertise with home addition permits saved us countless headaches with local building authorities!
Jennifer Park
San Jose, CA
Our complex second story home addition was handled masterfully by Mason and the Cecilia Home team. Their structural engineers designed a solution that minimized disruption to our first floor during construction. Their home addition specialists coordinated everything from structural support to roof matching. We now have double the square footage with stunning Bay Area views!
Andrew Thompson
Mountain View, CA
The in-law suite home addition Cecilia Home created for our property is perfect for our aging parents. Mason thoughtfully designed the space for accessibility while ensuring it complements our home's architecture. Their home addition expertise allowed for a separate entrance that gives everyone privacy, while still feeling connected to the main house. The quality of construction is outstanding.
Lisa Wong
Berkeley, CA
Our 800 sq ft home addition project with Mason at Cecilia Home was an excellent investment. Their team helped us design a two-story addition that maximized our narrow lot and seamlessly integrated with our existing California bungalow. Their knowledge of local building codes and home addition permit processes made what could have been a stressful project actually enjoyable.
Daniel Kim
Cupertino, CA
Cecilia Home transformed our single-story home with a beautifully designed second floor addition. Mason personally oversaw the architectural planning, creating a seamless design that looks like it was always part of our home. Their home addition specialists ensured everything was structurally sound while maximizing our budget. The new space has completely changed how our family lives!
Sophia Chen
San Francisco, CA
We hired Cecilia Home to design and build a master suite addition, and they exceeded all expectations. Mason's architectural vision created a space that perfectly balanced luxury with practicality. Their home addition team managed every aspect from foundation to finishing touches with remarkable precision. Our new master bedroom and bathroom have added significant value to our property.
Michael Rodriguez
Palo Alto, CA
The kitchen and family room addition Mason designed for our California home completely transformed our living space. Cecilia Home's team seamlessly integrated the new construction with our existing house, creating an open, light-filled area that's now our favorite gathering place. Their expertise with home addition permits saved us countless headaches with local building authorities!
Jennifer Park
San Jose, CA
Our complex second story home addition was handled masterfully by Mason and the Cecilia Home team. Their structural engineers designed a solution that minimized disruption to our first floor during construction. Their home addition specialists coordinated everything from structural support to roof matching. We now have double the square footage with stunning Bay Area views!
Andrew Thompson
Mountain View, CA
The in-law suite home addition Cecilia Home created for our property is perfect for our aging parents. Mason thoughtfully designed the space for accessibility while ensuring it complements our home's architecture. Their home addition expertise allowed for a separate entrance that gives everyone privacy, while still feeling connected to the main house. The quality of construction is outstanding.
Lisa Wong
Berkeley, CA
Our 800 sq ft home addition project with Mason at Cecilia Home was an excellent investment. Their team helped us design a two-story addition that maximized our narrow lot and seamlessly integrated with our existing California bungalow. Their knowledge of local building codes and home addition permit processes made what could have been a stressful project actually enjoyable.
Daniel Kim
Cupertino, CA
Cecilia Home transformed our single-story home with a beautifully designed second floor addition. Mason personally oversaw the architectural planning, creating a seamless design that looks like it was always part of our home. Their home addition specialists ensured everything was structurally sound while maximizing our budget. The new space has completely changed how our family lives!
Sophia Chen
San Francisco, CA
We hired Cecilia Home to design and build a master suite addition, and they exceeded all expectations. Mason's architectural vision created a space that perfectly balanced luxury with practicality. Their home addition team managed every aspect from foundation to finishing touches with remarkable precision. Our new master bedroom and bathroom have added significant value to our property.
Michael Rodriguez
Palo Alto, CA
The kitchen and family room addition Mason designed for our California home completely transformed our living space. Cecilia Home's team seamlessly integrated the new construction with our existing house, creating an open, light-filled area that's now our favorite gathering place. Their expertise with home addition permits saved us countless headaches with local building authorities!
Jennifer Park
San Jose, CA
Our complex second story home addition was handled masterfully by Mason and the Cecilia Home team. Their structural engineers designed a solution that minimized disruption to our first floor during construction. Their home addition specialists coordinated everything from structural support to roof matching. We now have double the square footage with stunning Bay Area views!
Andrew Thompson
Mountain View, CA
The in-law suite home addition Cecilia Home created for our property is perfect for our aging parents. Mason thoughtfully designed the space for accessibility while ensuring it complements our home's architecture. Their home addition expertise allowed for a separate entrance that gives everyone privacy, while still feeling connected to the main house. The quality of construction is outstanding.
Lisa Wong
Berkeley, CA
Our 800 sq ft home addition project with Mason at Cecilia Home was an excellent investment. Their team helped us design a two-story addition that maximized our narrow lot and seamlessly integrated with our existing California bungalow. Their knowledge of local building codes and home addition permit processes made what could have been a stressful project actually enjoyable.
Daniel Kim
Cupertino, CA
We are your trusted design and engineering experts.
Since 2019, Cecilia Home has delivered premium architectural design and construction solution across California. Our collaborative approach combines technical expertise with personalized attention, ensuring each project reflects your unique vision and exceeds your expectations.
