▼

Community Development - FAQs (Residential)

Show All Answers

1. What determines how large of an addition I can build on my house?

The size of all additions, including any detached structures, is regulated by lot coverage and floor area ratio, as well as by minimum building setbacks, maximum building heights, and a rear yard open space requirement. Additional parking may also be needed. These requirements, when applied to the size and shape of your existing house and lot, will determine the size and configuration of a potential addition on your property.

2. What is "lot coverage", what is "floor area ratio", and what is the difference?

"Lot coverage" is the total square footage of all the footprints of all the structures on a lot divided by the gross lot area and results in a percentage. Open projections such as patios, decks, balconies, and eaves are excluded. Different zoning districts have different lot coverage maximums. The maximum allowed lot coverage is 50% in the R-1 Zone and 40% in the R-1LD District. "Floor Area Ratio" (FAR) is the total square footage of all parts and all levels of all structures divided by the net lot area and results in a percentage. Some patios, most decks, and all balconies, as well as tall crawl spaces and high ceiling areas, are included. The maximum allowed FAR is 55% in the R-1 and R-1LD Zones. No other zoning districts have FAR limits. In calculating the maximum allowable size of most residential additions, floor area ratio, rather than lot coverage, will usually be the limiting factor.

3. What is the difference between "gross" and "net" lot area?

"Gross lot area" is the total square footage of a lot. "Net lot area" is the gross lot area minus the square footage of all easements and of all areas of slope greater than 30%.

4. How do I find out what size my lot is?

Gross lot area may be obtained from your official deed for the property or from the San Mateo County Tax Assessor Office in Redwood City.

5. How do I determine the slope on my lot?

The slope of land is measured in percentage and is the ratio of the vertical change in grade elevation to the horizontal distance over which that change occurs. For lots with slopes covering more than 10% of the property, it is advisable to hire a licensed surveyor to measure the steepness and calculate the area of the slopes if that information will affect your construction project.

6. What is a building setback?

A "building setback" is a line parallel to a property line which limits how close to the edge of the property a structure can be built. All setbacks are measured inward from all property boundaries. Certain building projections, such as porches, eaves, bay windows, and fireplaces, may be allowed to encroach a few feet into required setbacks.

7. How do I determine where my property lines are?

A property line is invisible. A street curb or sidewalk edge are usually not the true location of a residential property line. Measuring half the distance of the known right-of-way width of a street from the centerline of that street towards your house can provide the approximate position of your front property line, provided the street is centered within its right-of-way. A so-called "property line fence" is usually very close to the true location of a side or rear property line. Call the Public Works Department at 650-259-2339 to find out the right-of-way width of your street. However, the best way to accurately determine property lines is to hire a licensed surveyor to locate existing benchmark points and measure the boundaries of your property based upon the legal description contained in the official deed.

8. How long does it take to get a permit for an addition to my house?

All ground floor construction that fully complies with all applicable zoning regulations and building code requirements can typically receive a Building Permit within one month. Any ground-floor construction requiring a Use Permit or a Variance, and all second-floor construction will, on average, require two to three months to receive Planning Commission approval and may then be submitted for Building Permit approval. Especially complicated or controversial projects may take somewhat longer.

9. How large of a deck can I have?

The allowable size of a deck is based primarily upon floor area ratio, but both its size and shape will likely also be influenced by building setbacks and the configuration of the existing house, especially if the deck is to be located above the ground floor or on a sloping lot. Proximity of the proposed deck to neighboring homes in terms of potential impacts upon privacy is also an important consideration. An examination of the existing conditions on your site is needed to answer this question.

10. How high of a fence can I have?

In all zoning districts, the maximum height of a fence is 2.5 feet, if located within a required front setback or within any required setback abutting a street or alley; 6 feet, if located within a side or rear setback not abutting a street or if located outside of a required setback but facing a street or alley; and 8 feet everywhere else. Fence height is measured from the high side of the fence. Additional height of up to 18 inches is allowed for ornamentation and lighting on top of fence columns. A Fence Exception may be granted for additional non-decorative fence height in certain cases where safety or other considerations warrant. Some fence materials are prohibited in some areas.

11. What is a Use Permit and why would I need one?

A "Use Permit" is a deviation from a Zoning Ordinance regulation such as minimum 2nd-floor setbacks. City Planning Commission approval is required for all Use Permits. Approval requires justification based upon developmental constraints of the site and/or building. A Use Permit cannot be obtained to allow a land use not already allowed within a particular zoning district. A Use Permit differs from a Variance in that a Use Permit is available only for certain specified code deviations, while a Variance is needed for all other deviations and requires more extensive justification.

12. What is a Variance and how do I get one?

A "Variance" is a deviation from a Zoning Ordinance development standard such as maximum floor area ratio. City Planning Commission approval is required for all Variances. Approval requires the existence of a hardship based upon a unique physical characteristic of the site which prevents full compliance. The hardship cannot be economic or self-imposed, and the amount of deviation allowed will be what is warranted by the hardship. A Variance cannot be obtained to allow a land use not already allowed within a particular zoning district. Certain legal findings, as required under state law, are needed to for approval of a Variance.

13. What is the process for Planning Commission review of my project?

Planning Commission meetings are scheduled every first and third Monday of the month. The City mails notices of upcoming meetings to all property owners within 300 feet of the project site. The upcoming meeting agenda, staff reports, and project attachments are posted on the City's website and available for viewing at the Community Development Department on the Thursday prior to the meeting. The Commission may approve, deny, or continue a project at the Public Hearing. Applicant representation is required at all meetings. All meetings are open to the public and anyone may speak. After a Planning Commission action is taken at a meeting, there is a 10-day appeal period.

14. When will the Planning Commission meet on my project?

The Planning Commission meets twice a month, on the first and third Mondays, at 7 pm in the City Council Chamber at City Hall. The first meeting on a project usually occurs about a month after the date that a complete project application is submitted.

15. What are the chances that the Planning Commission will approve my project?

The Planning Commission approves over 95% of the residential projects it reviews; however, modifications are made to most of these approved projects.

16. What happens after the Planning Commission approves my project?

If the approval is on a matter for which the Planning Commission is authorized to take the final action, you will receive a letter for your signature indicating you accept all the conditions of project approval. You are then authorized to apply for a Building Permit. If the approval is on a matter for which the Commission does not have final action authority, the Commission approval is a recommendation to the City Council and the matter will automatically be scheduled for Council action.

17. What happens if the Planning Commission denies my project?

If the denial is on a matter for which the Planning Commission is authorized to take the final action, the decision may be appealed to the City Council by anyone within 10 calendar days. If the denial is on a matter for which the Commission does not have final action authority, the Commission denial is a recommendation to the City Council and the matter will automatically be scheduled for Council action.

18. How do I appeal a decision I don’t agree with?

Planning staff decisions may be appealed to the Planning Commission by contacting the Community Development Department. All final actions of the Planning Commission may be appealed to the City Council and must be submitted in writing to the City Clerk within 10 calendar days. All actions of the City Council are final, but there are usually appeals processes available through the court system.

19. Can the City recommend a good architect for my project?

The City does not endorse the services of any particular person or firm but strongly recommends that you hire a California-licensed architect for any building design project, especially one that requires Planning Commission approval. You can contact the California Architects Board or drive around the city looking for construction in progress and ask who the architect was.

20. What is the parcel number for the property at _____?

This information can be obtained from the Parcel Zoning Information table.

21. What is the zoning for the property at _____?

This information can be obtained from the Parcel Zoning Information table.

22. What are the development regulations for the _____ Zone?

This information can be obtained from the Municipal Code.

23. How many parking spaces are required for a _____?

This information can be obtained from the Municipal Code.