About San Mateo ADU Builder
Your local ADU builder serving San Mateo and the Peninsula. “Backyard Homes, Built Right”
Your Local San Mateo ADU Builder
San Mateo ADU Builder was founded with a simple mission: help Peninsula homeowners add space, income, and flexibility to their property with a well-built ADU. We know San Mateo's lot sizes, setback rules, and permitting process inside out — and we design every unit for California's by-right ADU approval.
We specialize in detached backyard ADUs, garage conversions, junior ADUs, prefab units, and home additions. As a single licensed general contractor we handle design, permitting, and construction under one roof — from a 400 sq ft studio to a full 1,200 sq ft backyard home.
Our team consists of trained, insured professionals who take pride in their work. We treat every home as if it were our own, and we don't consider a job done until you're completely satisfied.
Full Coverage
Licensed & Insured
San Mateo, CA
Locally Owned
7 Specialties
ADU Services
Always Free
Estimates
Our Commitment to You
Quality Workmanship
Every job is performed by trained professionals using commercial-grade equipment. We never cut corners.
Transparent Pricing
We provide clear, upfront quotes with no hidden fees. You know exactly what you are paying before we start.
Satisfaction Guaranteed
If you are not happy with our work, we will come back and make it right -- no questions asked.