24 hour adu — San Mateo, CA
Last updated: September 24, 2026
What affects the price
Building an ADU involves several moving parts that shape your total budget. The biggest factor is whether you choose a prefabricated unit or a custom build on-site. Site preparation is also significant; if your land requires extensive grading, utility trenching, or foundation work, costs will climb. Your choice of finishes—like kitchen cabinetry, flooring, and siding materials—also shifts the bottom line. We help you navigate these variables to find a setup that fits your property. Exact pricing confirmed free on the call.
About this service
This service refers to rapid-response consulting where a team reviews your site feasibility, zoning potential, and design goals within a single day. You need this if you are in the early research phase and want immediate clarity on whether your property qualifies for an ADU. It cuts through the uncertainty of property development by giving you actionable information about setbacks and utility access right away, allowing you to move forward with confidence instead of waiting weeks for an initial assessment.
Frequently asked in San Mateo
What is the cost of an Accessory Dwelling Unit in San Mateo?
The cost of an Accessory Dwelling Unit in San Mateo varies significantly. Factors include the size, chosen materials, and site accessibility. Permits and architectural plans also contribute to the overall expense. We provide free, detailed estimates after assessing your specific property needs. This ensures transparent pricing for your San Mateo ADU.
Can I get an Accessory Dwelling Unit construction cost estimate in San Mateo?
What is involved in ADU construction in San Mateo?
Are there modular Accessory Dwelling Units available in San Mateo?
Modular Accessory Dwelling Units offer a faster construction timeline and can be a great option for San Mateo. These units are often prefabricated off-site and assembled on your property. We can help you explore modular ADU solutions. They can be a cost-effective and efficient way to add living space.
What Accessory Dwelling Unit grants are available in San Mateo?
What is the Accessory Dwelling Unit permit process in San Mateo?
Can I find an Accessory Dwelling Unit for rent in San Mateo?
While we focus on building ADUs, many homeowners in San Mateo construct them for rental income. If you're looking to rent an ADU, you'd typically check local property listings. If you're interested in building one for rental purposes, we can certainly assist you with the entire process.
Also serving nearby: Hayward · Daly City · Oakland · Sunnyvale · Fremont
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of San Mateo — population 101,327; about 8,350 residents per square mile across 12.1 sq mi. ZIP codes covered include 94401, 94402, 94403, 94404, 94497.
Neighborhoods served in San Mateo: Bay Meadows, Edgewater, Fairway Park, Laurel Creek, San Mateo Village — and every surrounding area.
Areas we serve
Browse by state, then city.
California (4)
All of California · Rialto · San Buenaventura (Ventura) · San Mateo · Vacaville