There is potential for many thousands of new secondary housing units in single-family areas throughout San Mateo County, and more should be done to make these units easier to build, argued a Civil Grand Jury Report released last year.
San Mateo County cities were required to provide feedback on the report, and most communities were largely in agreement with the report's findings. Access the full report and responses here.
The availability of housing, especially housing considered "affordable" in San Mateo County is considered by county housing leaders to be at a crisis point, the report stated. About 68% of the county's land is protected from development as agricultural or open space, and of the already developed land, two thirds is occupied by single-family homes – of which there are about 155,000 within the county.
However, there are only about 4,000 known secondary units on those properties, the report stated.
Several rounds of laws passed at the state level that took effect in 2017 and 2020 are expected to make constructing second units easier for homeowners. For instance, just since 2017, the number of new second units in the county increased to an average of 269 per year, up from 60 per year in the years 2010 through 2016, according to the report.
And new laws that took effect on Jan. 1, 2020, streamlined the process further. These included laws that bar homeowner associations from banning secondary units, require local governments to include steps to incentivize and promote the creation of affordable second units in their general plans, and prohibit impact fees, additional parking or owner occupation requirements for second units that are 750 square feet or less in size. In addition, second units are not allowed to be used as short-term rentals, or those less than 30 days, in a move to discourage their use as vacation rentals.
In addition, in January of last year, the county started an amnesty pilot program for homeowners who want to upgrade existing non-permitted second units. It allows existing second units to be brought up to code and receive permits, and offers homeowners a no-risk option to back out of the process any time without having to bring the non-permitted unit up to health and safety standards.
Yet the biggest obstacles that remain to building new second units or upgrading non-permitted ones are obtaining financing, a limited supply of contractors willing to work on second units, and a limited number of inspectors recruited and trained by local governments, the report stated.
The grand jury then offered several recommendations. The county and cities within the county should keep reaching out to homeowners to let them know about the new laws that streamline the process to build and permit second units, the jury said. The county and its cities should figure out how to make a list of financial partners that can help homeowners secure funding to build or upgrade second units. They should develop a list of contractor resources and work with training institutions to recruit and train more general contractors and inspectors. And they should encourage homeowners whose second units are not permitted to get them permitted.
Various models have been studied to encourage jurisdictions to make second units more accessible to homeowners. For instance, San Jose has created a position called an "ADU Ally," who helps people with their questions about secondary units or accessory dwelling units (ADUs), while Napa and Sonoma counties have the Napa Sonoma ADU Center, which offers technical assistance and homeowner education. There is also a statewide association called the "Casita Coalition" that provides resources to policymakers and city professionals. The county is supporting creating a white paper to look at those approaches, according to the report.
Several communities weighed in on the reports with their own responses.
Menlo Park noted that the county is already working with the Casita Coalition's committee working on ADU financing strategies. A recent study in Menlo Park found that between 2010 and 2018, there were 126 violations at second units reported, or about 1% of all housing units citywide. About 78% of the unpermitted second units citywide are in the city's Belle Haven neighborhood, while most of the permitted second units are in other areas of the city, according to the city's response.
Menlo Park and other communities pushed back on the notion that a shortage of inspectors are an obstacle to building construction.
Other communities noted that while there are only 4,000 known secondary units, it's still not clear how many unpermitted second units exist throughout the county.