The Marin County Board of Supervisors on March 11 voted to extend an existing permit-fee waiver program for accessory dwelling units (ADUs) and junior ADUs (JDUs) through Dec. 31, 2026.

County staff described four fee-waiver tiers: $1,500 for eligible JDUs; $2,500 for standard ADUs; $7,500 total ($2,500 + $5,000) for deed-restricted ADUs affordable to moderate-income households (roughly $200,000 annual income for a three-person household in 2024) and $10,000 for deed-restricted ADUs affordable to lower-income households (up to approximately $141,000 for a three-person household in 2024). All waivers require the owner to certify the unit will not be used as a short-term rental.

Senior planner Aileen Tannillion told supervisors Marin has seen a steady rise in ADU permit activity — from roughly 35 applications in 2019 to about 90–94 applications a year more recently — and that building permits issued since 2019 number just under 303 for ADUs, of which about 153 have certificates of occupancy. Staff said about $200,000 in fee waivers were processed in the last two years and noted one deed-restricted low-income ADU is now occupied; three additional deed-restricted waivers are pending.

Supervisor questions focused on implementation details such as when waivers are applied (at permit fee assessment) and how the county tracks deed-restricted units. Staff said waiver approval occurs when permit fees are set and that owners of deed-restricted units must provide tenancy and income certifications that the county monitors.

The board approved the extension by motion; staff said the county also offers ADU resources including one-on-one feasibility consultations and preapproved plans through the ADU Center to reduce costs and time for homeowners.