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

Highland Municipal Code § 16.40.030(A) governs accessory structures in the City of Highland's residential districts. Under subsection A.1, an accessory structure, attached or detached, must meet the site development standards that apply to the main structure in its zoning district, except where the section says otherwise. Detached accessory structures follow subsection A.4. They can be located within an interior side yard or rear yard. Where one sits closer than five feet to an interior side or rear lot line, one-hour fire walls must be installed on the side or sides located within the setback, and in no case can the structure be closer than one foot from the property line. The maximum height is 20 feet and the maximum size is 1,000 square feet, and the building can be no higher than the main structure. Accessory buildings must be located at least 10 feet from any other building. Building larger than the size cap requires a staff review permit, approved by the planning commission, before building permits issue. That permit is a one-time approval and remains valid for the lifetime of the structure.

Several related rules sit in the same section. Canopies and patio covers attached to the main building can extend into a required rear yard, interior side yard, or street side yard if the projecting portion stays within 1,000 square feet and 20 feet in height, no closer than five feet to a lot line, and entirely open on at least three sides. Ground-mounted equipment such as air conditioning compressors, evaporative coolers and pool equipment can project a maximum of four feet into the required rear yard setback and a maximum of two feet into the required interior side yard setback, and is prohibited from projecting into the required front or street side yard setbacks. Porches, steps, eaves, chimneys and similar features can project a maximum of three feet into a required front or rear yard area. In nonresidential districts, accessory structures cannot be located within the main building frontage and must meet all of the setback requirements for the associated main buildings.