South San Francisco City Council
March 26, 2025

ADU Resource
Center of San Mateo
County
Anna Alekseyeva
[email protected]
ADUs in California & San Mateo County
2023 Data
State-wide
• 18% of new housing units
• 36% of low & very low-income units
• 32% of moderate-income units
San Mateo county
• 23% of total units
• 30% of Low and Very Low Income Units
• 4,500 new ADUs committed by SMC for
current RHNA cycle (2023-31)
South San Francisco
• 376 ADUs planned for 2023-31
• 60% Very Low and Low Income Source: HCD APR Dashboard Why do we like ADUs?
Multigenerational living
Aging in place
Housing for community Rental income
Environmental benefits Increased property values
Meeting RHNA goals
Drive housing production
and infill development
across the county by serving
as a one-stop-shop to help
get ADUs built
ADU Resource Center
ADU Resource Center’s Services
Provide homeowners with resources
to navigate the development process
✓ Suite of online resources
✓ Step-by-step guidance workbook
✓ Free feasibility consultations
✓ Personalized technical assistance
✓ Webinars
✓ Community outreach &
coordination
Work with jurisdictions to meet their
ADU policy goals
✓ Housing Element implementation
support
✓ HCD compliance & ADU
ordinance support
✓ Up-to-date information about
ADU laws and best practices
✓ Affordable ADU program
Evolving state laws continue to change the
ADU environment
State ADU statute has made ADUs much easier to permit
• Allowed in all residential zones; ministerial approval • Strong protections built in for ‘state-exempt’ ADUs
o ADUs up to 800 sqft
o All converted ADUs/JADUs
o Multifamily converted & detached ADUs
• One parking space max per ADU, with requirements waived in certain circumstances; no replacement parking
• No owner occupancy for ADUs permitted since 2020
• No impact fees for ADUs <750 sqft
• Up to 3 ADUs per property: 1 converted, 1 new detached, 1 JADU
• HOAs cannot prohibit or make ADUs more difficult / costly New laws (2024-5)
• Pre-approved plans: jurisdictions must allow
designers to get plans pre-approved by permitting
staff and posted online
• Legalization pathways for unpermitted units:
decreasing barriers to legalize unpermitted ADUs
• Multifamily ADUs: up to 8 detached ADUs
allowed on existing multifamily properties
• Condoization: allows jurisdictions to enable ADUs
to be sold separately from primary residence (via
local ordinance)
Affordable ADU program
Context
• Affordable ADU programs
have been piloted across CA
and in cities across the country
to encourage the utilization of
ADUs as affordable rentals or
to support lower income
homeowners
• 11 jurisdictions have
affordable ADU policy
commitments in their Housing
Elements
Typical components of an affordable ADU program
Incentivize homeowners to build and
rent their ADUs at below market rates
Financial incentive Homeowner
supports
Affordability
requirement
ADU Resource Center’s Services
Provide homeowners with resources
to navigate the development process
✓ Suite of online resources
✓ Step-by-step guidance workbook
✓ Free feasibility consultations
✓ Personalized technical assistance
✓ Webinars
✓ Community outreach &
coordination
Work with jurisdictions to meet their
ADU policy goals
✓ Housing Element implementation
support
✓ HCD compliance & ADU
ordinance support
✓ Up-to-date information about
ADU laws and best practices
✓ Affordable ADU program
Website includes suite of free resources:
www.smcadu.org
➢ Guidebook
➢ ADU Calculator
➢ Pre-Designed Plans
➢ Local rules
➢ ADU stories
ADU
Calculator
Homeowner technical assistance & education
Feasibility consults (free!)
– launching in April
• Free 1 hour feasibility
consults with ADU
expert
• Understand possibilities
and limitations of your
property
• Learn if ADU is right for
you
• Get next steps and
roadmap for the process
Homeowner Help Line Webinars
• Free troubleshooting
calls to discuss project
challenges
• Provide a go-to number
where counter staff can
direct homeowners
• Discuss how to find a
vendor, contractor
issues, budget and cost
considerations
Center’s member jurisdictions
• Atherton
• Belmont
• Brisbane
• Burlingame
• East Palo Alto
• Foster City
• Hillsborough
• Menlo Park
• Pacifica
• Portola Valley
• Redwood City
• San Bruno
• San Carlos
• San Mateo City
• San Mateo County
• South San Francisco
• Woodside
Questions? Ideas?
Anna Alekseyeva
[email protected]