Second Units and Junior Second Units

Resources for Homeowners

Resources for homeowners, including ADU regulations organized by city, can be found here. The San Mateo County Second Unit Online Center can be found at


New Accessory Dwelling Unit Laws

21 Elements Implementation Guidance and Checklist

Goldfarb and Lipman Webinar Slides and Webinar

State Law - As Chaptered

Goldfarb and Lipman Law Alert

HCD Guidance: Cover Letter and Memo 

League of Cities Guidance Memo

Sample Ordinances



Second Unit Resources

Affordability Research

Best Practices for Second Units San Mateo County FAQ Sheet

Amnesty Program for Second Units FAQ Sheet

Portola Valley Second Unit Manual

Santa Cruz ADU Manual

Sacramento County ADU Manual

Accessory Dwellings - a one-stop source on ADUs

HCD Bulletin on building code changes

Junior Second Unit Resources

Lilypad Homes: Lilypad Homes and City of Novato

Junior Second Units Fact Sheet PDF + Editable File