Planning and Building

• How Do I Make an In-person or Online Appointment?
• How Do I File a Complaint for a Code Violation?
• How Do I Submit a Planning Permit Application?
• How Do I Find Out More About the Planning Permit Process?

• How is the Height Limit Applied on my Property?
• How Do I Add an Accessory Dwelling Unit to My Home?
• How Do I Find My Property Lines?
• How Do I Find Out About an Easement on My Property?
• How Do I Trim or Cut Down a Tree?
• How Do I Trim or Remove a Tree in the Public Right-of-Way or Street?
• How Do I Find Out If My Parcel is Legal?
• How Do I Find the Zoning of My Property?
• How Do I Find the Zoning of My Property If It's Located Within a City?
• How Do I Subdivide My Property?

• How Do I Build a Fence?
• How Do I Build an Accessory Building?
• How Do I Build a Well on My Property?

• How Do I Find Out If My New Business Needs a Use Permit?
• How Do I Start a Home Occupation?
• When is a Use Permit Required for Businesses in Unincorporated San Mateo County?
  Anyone looking to open a business in Unincorporated San Mateo County should visit the Planning & Building Department and find out if their proposed business will require a Use Permit. Some business uses are restricted by the Zoning designations for a particular land or building site. Businesses can be cited for a Use Violation if the appropriate Use Permit has not been obtained. Go to the Planning & Building Division site for contact information and office hours.

• How Do I Apply for a Coastal Development Permit?
• How Do I Perform Vegetation Management for Fire Prevention in the Coastal Zone?

Requirements for off-street, electric vehicle (EV), and ADA automobile parking spaces and short- and long-term bicycle parking spaces vary depending on the project location and associated zoning.  For off-street parking and bicycle parking requirements, please refer first to the applicable zoning district regulations for parking requirements.  If the applicable zoning district does not establish parking requirements, then refer to the Parking section of the Zoning Regulations for off-street parking requirements by project type.  

The project may be eligible for reduced automobile parking requirements depending on its proximity to a major transit stop per AB 2097, approach to reduce vehicle-miles traveled associated with an environmental impact under CEQA, transportation demand management requirements from C/CAG, or project type (like multifamily affordable housing). See additional FAQs below and review Public Works’ guidance on traffic impact analysis. Note that relevant projects in the coastal zone will also need to comply with Local Coastal Program Policy 2.52.

Your project may be eligible for off-street parking requirement exceptions, including per Assembly Bill 2097 (AB 2097) (see FAQ below). If your project is subject to the C/CAG Transportation Demand Management Policy, you may be able to reduce required parking per Measure 15. If your project is subject to and has an impact per California Environmental Quality Act (CEQA) Guidelines Section 15064.3, Subdivision (b) Criteria for Analyzing Transportation Impacts, you may be able to reduce parking to address impacts. In addition, there are various reductions and exemptions available for specific types of projects through the local and state density bonus law: see the Density Bonus Chapter in the County’s Zoning Regulations. Note that in the event of a conflict between state density bonus law and local regulations, state law will supersede, and the density bonus law generally does not apply in the coastal zone. For other cases, please visit Off-Street Parking Permit Exception | County of San Mateo, CA.

AB 2097 (Government Code § 65863.2) eliminates minimum automobile parking requirements for most development within a half mile of a major transit stop. AB 2097 defines “public transit” as a “major transit stop” as that term is defined in Public Resources Code Section 21155. Public Resources Code Section 21155 further references Section 21064.3. Collectively, qualifying “public transit” for purposes of AB 2097 includes a “major transit stop” which is a site containing: (1) an existing rail or bus rapid transit station¹ (e.g., Caltrain, BART), (2) a ferry terminal served by either a bus or rail transit service (e.g., Oyster Point), (3) the intersection of two or more major bus routes with a frequency of service interval of 20 minutes or less during the morning (typically 6 – 9 am) and afternoon (typically 3 – 7 pm) peak commute periods (e.g., intersection of El Camino Real and East Market Street, due to SamTrans ECR and SamTrans 130, both of which have 15-min headways in peak periods), or (4) a major transit stop identified in the applicable regional transportation plan (e.g., Plan Bay Area-identified stops). 

For more information about AB 2097, review the California Department of Housing and Community Development Technical Advisory on the Implementation AB 2097.  Web mapping tools such as the Caltrans High Quality Transit Stops Online Map, with filter applied under “hqta_type” for major bus, ferry, rail or brt applied, can help with identification of potential stops and qualifying parcels.

If AB 2097 likely applies and you intend to use it to  seek a reduction in off-street parking requirements , provide the project planner with:  (1) map with stop location(s) and project location with a straight, direct line measurement in miles and feet from the nearest edge of the parcel containing the project site to the transit stop as pinpointed by a map sourcing data from 511.org (e.g., third party maps such as Google Maps) if it is within a public right-of-way, or to any point on the parcel(s) that make up the property upon which the stop is located. Map should include roadway network, parcel lines, APNs of project site, north arrow, scale, and legend. (2) Transit operator(s) and route number(s) that serve the location(s). (3) Hours of operation(s) and schedule during weekdays (6:00 – 9:00 a.m. and 3:00 to 7:00 p.m.) from the transit operators’ website with weblink to original documentation. This documentation will support verification by the project planner, as webtools and data may not be consistent with actual conditions.

In general, please consult the applicable zoning district (see Zoning Regulations) for parking design requirements.  If the applicable zoning district does not establish parking design requirements, then refer to the section of Parking the Zoning Regulations for off-street parking requirements.  

For on-street parking bays, please review San Mateo County Department of Public Works Standard Details Book.

In general, please consult the applicable zoning district (see Zoning Regulations) and, if applicable, Site Development design standards for bicycle parking and design requirements.  “Public” or “short-term” bicycle parking is typically provided near the entrance of a building and is available to serve visitors for shorter durations of time (about 2 hours or less).  See below for additional resources to support bicycle parking design and implementation:  

• Unincorporated San Mateo County Active Transportation Plan's Appendix C: Design Toolkit.
  • Page 52 of the toolkit (page 172 of 219 of pdf) includes short-term bicycle parking design guidance, including spacing and requirements for rack design. Bicycle parking provided in the public right-of-way or along a sidewalk must provide adequate clear width, per Building Regulations. “Private” or “long-term” bicycle parking is intended to serve residents or employees that are typically at a location for longer durations of time. Parking is often provided in a more secure location, and may be inaccessible to the public.
  • Page 53 of the Active Transportation Plan toolkit (page 173 of 219 of pdf) includes long-term bicycle parking design guidance for bicycle lockers.
• Redwood City Bicycle Parking Design Guidelines (June 2024)
• Association of Bicycle and Pedestrian Professionals (APBP) Essential of Bike Parking
• San Francisco’s Zoning Administrator Bulletin No. 9 Bicycle Parking Requirements: Design, Layout, and Calculation

The San Mateo County Department of Public Works manages on-street parking and parking restrictions, including new or modified curb markings to establish no parking, time-limited parking, loading zones, disabled parking, and passenger loading zones. Projects intending to establish new curb designations will need to work with Public Works. Visit their webpage. Additional requirements are identified in Title 7 of the San Mateo County Municipal Code, including Chapter 7.28 Miscellaneous Parking Regulations.

To apply online for a Building Permit, please login or register for a free account at our online Permit Center.

The staff reviews your plans and routes them to several other departments for their review, including:

• Current Planning
• Health
• Building Inspection Section
• Fire
• Public Works
• Public Utilities

Once you have made any required changes and all departments have given their approvals, we will send you a card telling you that you may pay your permit fees and receive your permit.

The fees for a permit, plan check, and other services vary depending upon a number of factors. You may get a current fee schedule and pay your fees at the permit counter.

Different building projects have different requirements (for instance, a single-family home permit requires far more extensive plans, fees, and inspections than a permit to re-roof a single-family home). For questions on requirements, please call the building counter at (650) 599-7310.

When plans are required for a permit, they must be drawn to minimum scale on substantial paper. Please refer to our document Plan Requirements for further information. Your drawings must be legible and must be complete enough to describe accurately how you will accomplish the proposed work.

For minor projects such as most decks, kitchen remodeling, bathroom remodeling, and even some small additions, you do not need an architect. However, if you are unfamiliar with drawing techniques, construction codes, symbols, or terminology, you should consider obtaining the services of a qualified draftsperson. For major projects, we encourage you to consider hiring a licensed architect or engineer.

Permit fees vary depending on the type of permit. A permit technician can provide you with an explanation of the fee schedule and, in many cases, an estimate of the fees for your project.

The length of time it takes to process a permit depends on the type of permit you are applying for and your property's location. If your property is within an area that is subject to certain discretionary planning permits, such as Design Review, Coastal Development, or similar planning permits, your processing time will increase. The volume of permits in process and the complexity of your project can also affect processing time. We review permits on a first-come, first-served basis, but we speed up the process for minor projects, such as those mentioned in Question 2, by reviewing them separately from the more complicated ones.

San Mateo County has a variety of geologic conditions ranging from expansive soils to seismic fault conditions. A geotechnical review can identify potential problems and ensure that you have incorporated proper engineering measures into your project design. In many cases, the State of California has mandated that you make specific measures a part of your design. The purpose of this process is to help you to protect your property, your neighbors, and yourself from the physical and economic injury that some geologic conditions can cause.

Permits do have term limitations. Large projects such as new residences and additions are valid for one year and can be renewed for a second year without additional fees. Projects such as decks, water heaters, electrical services, and similar permits are valid for one year to start construction. In addition to the term limits associated with a permit, you must also obtain a progress inspection at least every 180 calendar days once a project has started. This inspection must demonstrate substantial progress in one or more significant trades. If, for any reason, you are unable to have a valid progress inspection, you must request an extension "prior" to the expiration of your permit. All requests for an extension must be submitted in written form, and why you are requesting the extension must be stated. Failure to obtain an inspection or an extension will result in the expiration of your permit.

The only exception to term limitations is Fire System Permits, which do not expire.

The County Assessor's office is the primary source of information about your property. Ask for a copy of the parcel history for your parcel. This history is typically one or two pages with dates of all building permits and general data about construction. The Assessor's office can be reached at (650) 363-4500.

For more detailed records - particularly for construction since 1982 - you may submit a public records and research request directly to Planning and Building. For more information please visit our Public Records and Research Requests page.

See the San Mateo County Office of Sustainability's Guide for Contractors & Home Owners, pages 5-7.

Second units, also known as “accessory dwelling units,” (or “granny units,” “in-law units,” and various other names) are smaller units built on the same property as, or attached to, an existing primary residence. . . . View More

Noise sources associated with demolition, construction, repair, remodeling or grading of real property can take place between the hours of 7:00 am and 6:00 pm. on weekdays, 9:00 am and 5:00 pm on Saturdays, never on Sundays, Thanksgiving Day or Christmas Day.

Counter Service Appointments
The Planning and Building Counter on the 2^nd Floor is open to the public from 8:00 am - 4:00 pm, Monday - Thursday (closed 12:00 - 1:00 pm for lunch) and closed Friday - Sunday. We strongly encourage you to make an appointment for a virtual or in-person meeting with a Planner or Building Technician through our appointment system. (See instructions for using virtual appointments.) We make every effort to accommodate drop-ins as availability allows, but suggest scheduling an appointment to ensure we can serve you effectively.

Environmental Health
Thursday, 7:00 am - 10:30 am
Call Edgardo Diaz at:
(650) 363-1820, Planning Office
(650) 372-6200, EH Office

View our detailed instructions on how to create an in-person or online appointment.

The Code Enforcement Unit investigates suspected violations. After each investigation in which a code enforcement officer determines that a violation exists, the officer issues a Notice of Code Violation or a Notice and Order to Abate to the person responsible.

What happens depends upon the type of violation.

If an officer finds that someone is violating a zoning regulation, for example, operating a prohibited business at home, the officer may refer the matter to the County Counsels Office, which could file suit against the violator.

If the officer finds that the matter involves a public nuisance, such as an abandoned car or a large amount of refuse collecting in a yard, he will issue an abatement order. The person receiving that order has 10 days in which to correct the situation. If it is not corrected, the County may step in, "for example, by having the car towed or the refuse removed." The property owner is then billed for actual costs plus a 15% administrative fee.

You cannot appeal a notice that you are violating zoning regulations. You can appeal an abatement order by filing a written request for a hearing with the County Officer who ordered the abatement.

The Abandoned Vehicle Hearing Officer hears appeals involving abandoned vehicles.

The Board of Supervisors hears appeals involving nuisances.

Anyone can report what he or she believes to be a code violation. You can report a violation by coming to the DRC and completing a complaint form, by writing a letter to the Code Enforcement Section, or by phoning Code Enforcement, (650) 363-4825, and requesting that a Code Enforcement Officer return your call. The line has an answering machine 24 hours a day.

It's best to provide your contact information when submitting a complaint. This ensures that County staff has the ability to contact you with any questions or updates. Someone may request the complainant's information but must submit, in writing, a valid reason for wanting it. This request must then be approved by San Mateo County Counsel prior to release. When necessary, the County will accept an anonymous complaint.

If the Code Enforcement Unit verifies that there is a violation, the staff will take enforcement action. If they believe the problem to be a disagreement between neighbors, they may refer you to the Community Services Mediation Program, (650) 363-4841.

Call the Code Enforcement staff at (650) 363-4825.