San Mateo ADU Developer — Garage, Home, and Backyard Builds.
About SYMBiHOM in San Mateo
San Mateo homeowners are at the center of the Peninsula's most active residential rental market. With strong commute access, high renter demand, and a city that maintains its own Pre-Approved ADU Plans Program, the path to a fully permitted ADU — whether from a garage, interior home space, or a backyard — is well established. SYMBiHOM is a CA HCD approved ADU Design-Build Developer serving San Mateo homeowners.
Our Credentials in San Mateo
SYMBiHOM holds CA HCD approval and is actively pursuing pre-approved vendor status with the City of San Mateo. The City of San Mateo operates its own Pre-Approved ADU Plans Program with a two-phase review process. San Mateo County also participates in the GLADUR program through HEART of San Mateo County, providing additional free plan resources.
Permitting in San Mateo
The City of San Mateo Pre-Approved ADU Plans Program uses a two-phase process: Phase 1 is designer pre-approval and gallery listing; Phase 2 is site-specific review. No changes to the pre-approved design are permitted in Phase 2. The program was revised in January 2025 and includes HCD Factory-Built and HUD Manufactured ADU options.
Animation of Symbihom’s Garage Conversion
What We Build
• Attached or detached garage conversion — studio, 1BR, or 2BR, 300–850 sq. ft.
• Junior ADU (JADU) — attached garage, up to 500 sq. ft.
• Home conversion — convert underutilized interior space into a fully permitted ADU
• Backyard ADU — new detached unit on your existing lot
• State-approved factory-built panel system
• Fully customizable finishes — cabinetry, flooring, fixtures
• ADA-accessible design available
• Sub-metered electricity and water available
Timeline:
Typical build: 4–6 weeks after permits are issued. Designs are customizable across garage conversions, home conversions, and backyard ADUs.
Is Your Property Eligible?
The lot must be zoned residential with an existing single-family home or duplex, and must not be located in a geohazard, landslide, flood zone, or Wildland-Urban Interface area. The property must not have an open Code Enforcement violation.
Not sure if your property qualifies? Fill out the form below. We check zoning and flag any issues before you spend anything.