Placer County, CA Accessory Structures: ADU Impact Fees (2026)

Section 15.65.110(B), part of the county's Affordable Housing Ordinance, lets a property owner or developer who voluntarily deed-restricts an ADU of 750 square feet or greater for affordability exempt that unit from building permit fees and from the fees charged under Chapter 15, Article 15.28 (County Road Network) and Article 15.34 (Parks and Recreational Facilities Fees). The owner must provide written verification that the unit is deed-restricted before the county grants the exemption; without that paperwork, the standard fee schedule applies. This incentive sits alongside a separate, narrower fee break at Section 15.70's connection-fee provisions for deed-restricted ADUs tied to Placer County Code Chapter 17, Article 17.56, Section 17.56.200, which exempts qualifying deed-restricted ADUs from sewer inspection-permit fees.

Outside of a deed restriction, ADU owners are not automatically exempt from impact fees: Section 15.65.100(C) bars issuance of a building permit for any project subject to the affordable housing article until the affordable housing obligation, or an applicable fee, has been satisfied. The affordable housing fee itself carries a 3% administration component and is adjusted every July 1st using the Engineering News-Record Building Cost Index, per Section 15.65.100(D), so an ADU that does not qualify for the deed-restriction exemption remains subject to the county's regular development fee structure, including sewer service charges computed at 0.714 equivalent dwelling units for a standard ADU.