Frequently Asked Questions
1) How do I find my property lines?
This can be difficult, but we have several suggestions:
We can provide you with a copy of the Assessor's map, which will show an outline of your property according to the dimensions on your deed.
In rural areas, or in other areas where there may not be a regular lot pattern, you may have to reference an existing or obtain a partial or full survey from a licensed land surveyor or civil engineer.
In urban areas, you may sometimes determine the location of your front lot line once you know the width of the right of way in front of your property (a staff member at the counter can help you to find out the width). For example, suppose the width of the right of way is 50 feet. Your front property line will be located approximately one half that distance, or 25 feet, from the middle of the right of way.
Fence lines are not necessarily a good indicator of property lines and should not be relied upon for drawing plans and determining setbacks.
If in doubt, hire a licensed land surveyor. Depending on the type of project you are proposing, you may need to obtain a full or partial boundary survey of your property for submittal with a planning or building permit application. A boundary survey is required for work within five feet of a required minimum setback.
2) How can I find out about an easement on my property?
You can either review your title report to determine if one has been recorded as part of your legal description. You can also contact the Department of Public Works to help determine if any exist on your property.
3) I've been told that my house is on an "illegal parcel." I've been living there for years and paying taxes regularly. How can the property be illegal?
A legal parcel is one that (1) was created with the approval of the County, or (2) did not require County approval at the time it was created. Other parcels are considered "illegal," and you may not be allowed to develop the property until this problem is resolved. The County is authorized to file a Notice of Violation with the County Recorder's Office, which will show up on any future title reports. You can apply to have the parcel legalized, and the County will do everything possible to help you to solve this problem, particularly if you are doing your best to comply with the law. For more information, read the Revised Criteria and apply for a Certificate of Compliance.
4) Can the County provide zoning information for areas within city boundaries?
Unfortunately, we do not retain any zoning classification within our maps for incorporated areas. Please contact the incorporated jurisdiction′s Planning & Building department for that information. See Other Agencies & Contacts.
5) Can I subdivide my property?
Numerous factors need to be considered when determining is a lot is able to be subdivided. First and foremost, it must be demonstrated that subdividing will create lots that will be in conformance of their respective land use density and zoning development standards (minimum lot size & minimum lot width) and capable of development in accordance to the zoning regulations (setbacks, lot coverage, etc). Other agencies such as water and sewer providers should be contacted to determine if such services are available to a subdivided lot to develop. Other agencies like Environmental Health Department, Department of Public Works, and the Fire Department will also need to be contacted to discuss the feasibility of a subdivision. Given the various factors involved, please consider dropping by our office to discuss the subdivision process with a planner. For more information, please read our Subdivision Regulations.
6) I want to build a fence. What restrictions are there on height and similar matters?
Generally, in all Zoning Districts, your fence may not be more than 4 feet high in the front of your property or, in the case of a corner lot, more than 4 feet high on any side facing the street. In addition, the first 20 feet (from the front yard) on the side property may not be more than 4 feet high, or in the case of a corner lot, the first 10 feet along the side of the rear property from the street may not be more than 4 feet high. It may not be more than 6 feet high on the sides or rear. (Measured from the lowest adjacent natural grade.) Exceptions are possible for areas outside of the Coastal Zone.
Building permits are required for fences constructed above retaining walls. You do not need a building permit if the fence meets zoning requirements and is wooden or cyclone.
For more detailed information, please read our pamphlet How to Apply for a Permit to Build a Fence or refer to Section 6412 of the San Mateo County Zoning Regulations.
7) Do I need a permit to trim or cut down a tree?
You will need a permit to trim or cut down a tree if the tree is classified as a live Significant Tree or a Heritage Tree. A Significant Tree has a trunk circumference of 38 inches or more measured at 4-1/2 feet above the ground, except in the Emerald Lake Hills Design Review district, where trunk circumference is 19 inches or more. Heritage trees include all Santa Cruz Cypress and Oregon White Oak, plus certain other trees depending upon their size and location. A detailed list of these, including their qualifying sizes, is available at the Planning counter. In some cases, you will need to submit a report prepared by a licensed arborist that assesses the general health of the tree(s). Where trees are proposed for removal due to proposed development, it is best to assess such removal at the time such development plans are also submitted. For more detailed information, please read the Significant Tree Regulations and Heritage Tree Regulations.
8) Can I trim or remove a tree in the public right-of-way or street?
You will need to contact the Department of Public Works at (650) 599-1852.
9) Can I mail-in or email my Planning Permit Application?
At the moment, all planning permit applications must be submitted, with fees, in person to our office.
10) What are the Steps in the Planning Permit Process?
If a planning or zoning permit is required, it generally needs to be processed prior to application of a building or construction permit. The Planning Section of the Planning and Building Department processes these permits.
Most planning and zoning permits require some type of notification to surrounding owners or residents and often a public hearing before the county Zoning Hearing Officer, Planning Commission, or Board of Supervisors. In In reviewing and processing your permit application, the assigned planner will generally complete the following steps:
Initial Application Review: The planner reviews your project to determine whether your application is complete. During this stage, the planner discusses your project with a development review committee of senior staff members. The County generally has 30 days after receiving your application to notify you if you must provide any additional materials or information before your application can be processed.
Preliminary Research: The planner determines whether your project conforms with the County's General Plan, Zoning Ordinance, and other regulations and identifies what issues, if any, must be resolved before the application can proceed to a decision.
Referral to Other Agencies: The planner lets other agencies and applicable homeowners associations or community groups know about your project and solicits their comments and recommendations regarding compliance with their requirements.
Field Inspection: The planner verifies conditions on your project site, observes the surrounding land uses, and evaluates the potential impacts of your project.
Environmental Review: This review ensures that your project complies with requirements of the California Environmental Quality Act and evaluates its potential impact on the environment.
Preparation of a Staff Report: The report informs Department management, the Zoning Hearing Officer or Planning Commission, the applicant, and others of the staff's findings, recommendations, and conditions of approval.
Public Notification: State and local ordinances require that we notify surrounding owners or residents and the general public of most proposed projects and any required hearings.
Public Hearing: If required, a public hearing allows the public to provide information, comments and suggestions on your project before the County makes a decision. Once a decision is made, usually at the conclusion of the public hearing, both you and the public can appeal most planning and zoning permit decisions to a higher authority within a specified period of time. Staff or Zoning Hearing Officer decisions generally can be appealed to the Planning Commission. Planning Commission decisions, except for those concerning a request for a Home Improvement Exception or a variance, can be appealed to the County Board of Supervisors.
11) What if I can not find the information online?
Please feel free to contact our Planning information counter at (650) 363-1825 and we can assist you to get the information you need.
12) Can I schedule an appointment with a planner?
Planners are available on a drop-in basis with a minimal wait at our office to discuss any planning related inquiry. If you feel your inquiry may require detailed research, please feel to contact us to determine if making appointment will be necessary.
13) How can I file a compliant for a code violation?
If you suspect a violation of the Zoning Regulations, please identify the section of code that has been violated and complete the Violation Complaint Form. A completed complaint form can be emailed to firstname.lastname@example.org or mailed to the attention of the Code Compliance Section, 455 County Center, 2nd floor, Redwood City. A submitted complaint will result in the opening of a “VIO” or “SWN” case; please allow 2 weeks for staff to open a case. Once a case number has been assigned, please use this case number to track the status of the complaint online. To check the status of the complaint, please enter the property’s APN or address into the Online Permit Center.
To reach a Code Compliance Officer, please call 650-363-4825 and leave a message or visit the office at the address above. Our office hours are Monday through Friday, 7:30am - 5pm.
14) What do I need to do in order to have a well on my property?
You need a well construction permit. If you are in the coastal zone and want to install a well, you may also need a Coastal Development Permit (CDP). You can apply for the well construction permit at the Office of Environmental Health on the fourth floor of the County Office Building and for the CDP at Planning on the second floor. In the Coastal Zone, the CDP (or a CDP exemption) must be approved before the Environmental Health Division can issue the well drilling permit.
15) Do I need to go through the Coastal Commission to apply for a coastal development permit?
No. Coastal Development Permits are processed by the County, although certain CDPs approved by the County may be appealed to the Coastal Commission.
16) Does Vegetation Management Plan for fire prevention in the Coastal Zone require a permit?
If acivities follow the policy pertaining to Vegetation Management in the Coastal Zone, you will need a Coastal Development Exemption Permit.
17) Accessory Building: How many detached buildings can I have? Do I need a permit? What are the regulations?
Section 6410 and 6411 of the Zoning Regulations govern the number, size and location of accessory buildings in residential zoning districts. These regulations allow for the construction of only one (1) detached accessory building. A recent (February 2015) interpretation allows the construction of one additional detached building in addition to a detached garage. No building permit is required for the construction of an accessory building with a roof area of less than 120 sq. ft. in size, 8-feet in height or less, with no utilities or electricity, and complies with Zoning Regulations (specifically those regarding setbacks, lot coverage, and floor area). See Zoning Regulations.
18) When is a Use Permit Required for Businesses in Unincorporated San Mateo County?
The regulations pertaining to the Zoning District in which the property is located will describe the permitted uses for the property, or uses which can be established without a Use Permit. The Zoning District will also describe those uses which are conditionally permitted uses, or uses that can only be established after the issuance of a Use Permit by the County.
A parcel may have only one Zoning District (e.g., “RM”, “TPZ”), may have 2 Zoning District layers (e.g., R-1/S-101) or may have several Zoning District layers (e.g., R-1/S-17/DR/CD). Each “layer” represents a distinct chapter or section in the County’s Zoning Regulations. Typically, the first zoning district layer (e.g., C-1, M-1) describes the allowed uses for the area, with the exception of the C-1/NFO, M-1/NFO, M-1/Edison/NFO districts (among others) which, despite having 2 or 3 layers, are each a singular zoning district. Please review the permitted and conditional uses for the first layer of your Zoning District in the Zoning Regulations. To find the Zoning District that pertains to your property, please go to Find My Zoning, Parcel Map, and Other Property Info. See Zoning Regulations.
If a use permit appears to be required, please visit our Use Permit page and/or contact Current Planning Section staff at the counter or at (650) 363-1825. Planning staff will perform a New Business Zoning Conformance Review upon formal submittal of the completed form, proposed site plan and floor plan (if available), to the Planning Counter.
19) Can I operate my business out of my residence?
A home occupation is the operation of a business in a residence. Within certain guidelines, some occupations are permitted in any of the following districts: RE, RH, R-1, R-2, R-3, R-3-A, RM, RM-CZ, and PAD. Section 6102.46 of the Zoning Regulations establishes limits for home occupations. Customary, incidental home occupations conducted within a dwelling are allowed (with no separate permit requirement), provided that no retail business of any sort is involved; no stock in trade is kept, or commodity sold, except for the sale of commodities made on the premises; no person not a resident of the premises is employed; and an area not larger than one-fourth (1/4) of the floor area of the ground floor of the dwelling is devoted to such home occupation; provided, however, that such home occupation shall not require internal or external alterations, or involve construction features, or use of equipment not customary in dwellings; that the entrance to the space devoted to such occupation be from within the building and that no display pertaining to such occupation be visible from the street.
Regarding signage, only one sign or name plate, not exceeding two (2) square feet in area and containing the name and occupation only, shall be permitted in connection with each such home occupation, which sign or name plate shall be attached flat to the dwelling and shall not be illuminated. Please see the Requirements Concerning Home Occupations in San Mateo County.
20) What are your office hours?
Development Review Center Hours: Monday - Friday
Tel: (650) 363-1825
Tel: (650) 599-7311 for 24 hr. Automated Inspection Scheduling System, call (650) 306-8415
Tel: (650) 363-4161
Environmental Health: Thursday and Friday, 7:00 am - 10:30 am
Tel: (650) 363-1820, Planning Office
Tel: (650) 372-6202, EH Office
21) In Residential Zoning Districts, when do attics and basements not count toward Building Floor Area?
The intention of the Building Floor Area standard is to limit the bulk and mass of buildings. As such, attic and basement areas will not count toward Building Floor Area if all of the applicable criteria contained in the “Criteria for Attic and Basement Are Exemption from Building Floor Area," (dated August 24, 2012) are met and, in the opinion of the Community Development Director, if the areas do not contribute to the visual bulk and mass of the building.