About
Andrea Costanzo
Residential Designer
Since 2000, Andrea has helped Bay Area homeowners design ADUs, remodels, additions, and new homes — guiding each project through design, city approvals, permitting, and construction.
Placeholder photography — to be replaced with Andrea's project photos.
2000
Serving the Bay Area since
100+
ADUs designed and completed
25+
Years of residential design
A Local Practice
Designing a home is about more than drawings. Every city has its own process, requirements, submittals, and review expectations — and knowing how local departments read a set of plans is often what keeps a project moving.
Andrea has worked with homeowners throughout the San Francisco Peninsula for more than two decades. Her experience spans ADUs and garage conversions, kitchen and whole-home remodels, second story and family room additions, and custom homes.
She works directly with each homeowner — no handoffs — from the first consultation through construction, so the home that gets built is the home that was designed.
Serving San Mateo, Burlingame, Millbrae, South San Francisco, Belmont, San Carlos, Hillsborough, Foster City, Redwood City, and nearby Peninsula communities.
How We Work
A clear path from first conversation to finished home
- 01
Consultation
Share your goals, ideas, and vision.
- 02
Design
Develop plans tailored to your home and budget.
- 03
Permits
Navigate city reviews and approvals with confidence.
- 04
Construction Support
We'll stay involved throughout the building process.
Ready to start?
Let's Talk About Your Project
Whether you're planning an ADU, remodeling your home, building an addition, or building a new home, we'd love to hear your ideas.