San Mateo ADU Builder.
Peninsula scale, fixed-price clarity.
San Mateo runs its own building department with a measured plan-check pace. Lot patterns vary widely — bungalow-scale Hayward Park, larger San Mateo Park parcels, and 1950s tract Hillsdale all behave differently in feasibility. Tenant demand on the Peninsula puts ADU 1BR rents among the strongest in the region.
Licensed California contractor · CSLB #1098432 · Bay Area desk · City of San Mateo Community Development
City-specific deep dives
- Cost guideSan Mateo line-item budget guideEvery line item, 2026 prices, no surprises. The number you should be quoting from.
- Permits guideSan Mateo permits: fees & review windowsPlan-check workflow, fees, and realistic turnaround for this jurisdiction.
- Timeline guideSan Mateo project timeline — phase by phasePhase-by-phase schedule grounded in active builds, not optimistic Gantt charts.
About ADU work in San Mateo
We design and build detached ADUs, garage conversions, kitchen and bath remodels, and full additions across Hayward Park, San Mateo Park, Hillsdale, Aragon, and the Baywood Park corridor.
What the San Mateo ADU math actually looks like.
- Permit timeline
- 4–6 months
- 1BR ADU rent (San Mateo)
- $2,800–$3,600/mo
- Typical project cost
- $305K–$470K
What we resolve before drawings begin.
- 01
San Mateo Park historic awareness
Several pockets carry design review for street-visible work; we design to the published criteria.
- 02
Sea-level flood overlay (eastern edge)
Parcels east of El Camino can trip flood-zone elevation requirements. We confirm at feasibility.
- 03
Utility upgrades
Older Peninsula housing stock — 100A panels and aging water taps are common pre-ADU line items.
San Mateo neighborhoods we serve
- Hayward Park
- San Mateo Park
- Hillsdale
- Aragon
- Baywood Park
San Mateo services we deliver.
All Bay Area services →- Bay Area ADU BuilderOpen bay area hub →
- Bay Area Garage ConversionOpen bay area hub →
- Bay Area JADU BuilderOpen bay area hub →
- Bay Area Home AdditionsOpen bay area hub →
- Bay Area Kitchen RemodelingOpen bay area hub →
- Bay Area Bathroom RemodelingOpen bay area hub →
- Bay Area Whole Home RemodelingOpen bay area hub →
- Bay Area RoofingOpen bay area hub →
- Bay Area Siding & StuccoOpen bay area hub →
- Bay Area Decks & Outdoor LivingOpen bay area hub →
- Bay Area Concrete & FlatworkOpen bay area hub →
- Bay Area Windows & DoorsOpen bay area hub →
- Bay Area Foundation Repair & ReplacementOpen bay area hub →
- Bay Area Framing & Structural WorkOpen bay area hub →
- Bay Area Seismic RetrofitOpen bay area hub →
- Bay Area Hillside ConstructionOpen bay area hub →
- Bay Area New Home ConstructionOpen bay area hub →
- Bay Area Commercial Tenant ImprovementOpen bay area hub →
- Bay Area Multifamily RemodelingOpen bay area hub →
- Bay Area HOA Construction ServicesOpen bay area hub →
- Bay Area Property Management ConstructionOpen bay area hub →
Other Bay Area cities we serve.
San Mateo · ADU FAQ
Questions San Mateo homeowners ask first.
Start a San Mateo brief. We'll confirm flood zone, design review, utility scope, and a fixed-scope contract.
Are San Mateo ADU rents really that strong?
Yes — Peninsula tenant demand from the biotech and tech corridors keeps 1BR ADU rents in the $2,800–$3,600 range.Do I need flood-elevation drawings?
Only if your parcel sits in FEMA Zone AE or VE — mostly the eastern edge. We pull FEMA layers at feasibility.
More research for San Mateo
- Line-by-line adu pricing for San MateoCost transparency
- San Mateo ADU rental yield modelFinancial modeling
- Financing options for California ADUsCapital options
- Cost FAQ for San Mateo homeownersFAQ — Cost & Budget
- San Mateo permit FAQ — timelines, fees, plan checksFAQ — Permits & Code
- Realistic timelines for San Mateo projectsFAQ — Timeline & Phases
- Financing FAQ — loans, escrow, drawsFAQ — Financing & ROI
- Design choices that drive San Mateo adu valueFAQ — Design & Specs
- Renting an ADU in San Mateo — rules and yieldsFAQ — Rental & Tax
- San Mateo owners often also consider Beverly HillsCross-city signal
- Compare adu in San Mateo vs Santa MonicaCross-city signal
- San Mateo owners often also consider PasadenaCross-city signal
- Long Beach adu — permits & turnaroundCross-city signal
- Burbank adu — permits & turnaroundCross-city signal
- ADU in nearby GlendaleCross-city signal
- Browse every city we build ADUs inService hub
- Deep dive — ADU vs SB9 lot split: which path actually fits your lotEditorial deep-dive
- Will your ADU trigger a property tax reassessment?Editorial deep-dive
- Read: LADWP, SoCalGas and your ADU: the utility connection mapEditorial deep-dive
- Deep dive — Hillside ADUs in LA: soils, grading, and the geo reportEditorial deep-dive
- Case study: Culver ConversionProof of work
- See our Manhattan Beach Studio in San MateoProof of work
- Browse legalPillar guide
- TimelinePillar guide
- ADU — glossary entryEntity definition
- JADU — glossary entryEntity definition
- Definition: Detached ADUEntity definition
- Definition: Attached ADUEntity definition
Begin your projectin twenty minutes.
A short feasibility review of your lot — what you can build, roughly what it costs, and how long it will take. Free of charge. No sales call afterwards unless you ask for one.
- No obligation
- Reply within 24 hours
- BBB A+ Accredited