Placentia, CA Accessory Structures: Shed & Carport Rules (2026)

Section 23.81.120(e) is the core location rule for accessory buildings. An accessory building that is attached must be made structurally a part of, with a common roof with, the main building, and then complies in all respects with the main building requirements. A detached accessory building in an R district must be on the rear one-half of the lot, at least 10 feet from any dwelling existing or under construction on the same lot or any adjacent lot, not within 5 feet of any alley, not within 1 foot of the side line, and on a corner lot must not project beyond the front yard required or existing on the adjacent lot.

The R-1 sections add more. Section 23.12.040 caps accessory building height at 20 feet. Section 23.12.020 lists accessory buildings as permitted and bars constructing them before the main building is established. Section 23.12.080 gives room additions and accessory structures the same side setback as main buildings, 6 feet on one side and 10 feet on the other, except that where the main building's existing setback is smaller, the addition or accessory structure can be built to that existing setback. It sets a 10 foot rear setback for room additions, accessory structures and enclosed patios, and 5 feet for patio covers.

The two sections print different side distances for a detached accessory building: 1 foot in § 23.81.120(e) and the 6 and 10 foot figures in § 23.12.080(a)(2). Both are in the code, and Development Services applies them to a specific lot.

Related permits: guesthouses in R-1 need a use permit (§ 23.12.030). Elevated decks, balconies and similar structures in the R-1, RPC, PUD and SP-7 zones need a special use permit under § 23.81.055, with a decision date at least 21 days after a complete application, notice to owners within 100 feet, and a 10 calendar day appeal window. In any C or M district, § 23.81.060 allows accessory buildings only when constructed concurrent with or subsequent to the main building. Accessory dwelling units fall under Chapter 23.73. Whether a particular shed needs a building permit is a Title 20 question that this page does not answer.