Building on a hillside in Antioch: the local rules

Each rule below links to the section of the Antioch Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Antioch's code says

Antioch code What Antioch's code adds
Grading and retaining walls	No grading unless it is specifically shown on an approved final development plan. Applies: Parcels in hillside areas covered by the hillside article. § 9-5.2408 · code text Any parcel of land subject to this article shall not be graded unless such grading is specifically shown on an approved final development plan. Mass grading is generally not allowed. Applies: Hillside areas; grading of less significant land forms may be allowed. § 9-5.2408 · code text While mass grading is generally prohibited, the grading of less significant land forms is allowable, as is the grading of more significant natural features, provided such modifications will result in an improvement of the overall project and are in keeping with the overall intent of this article. Grading should generally be limited to the part of the site needed for the building and a limited outdoor area. Applies: Steeper areas and areas that are more visible. § 9-5.2408 · code text In steeper areas and areas of greater visibility, grading should generally be limited to that portion of the site required for the structure and limited associated outdoor area.
When hillside rules apply	Hillside rules apply where most of the area has slopes over 10%. Applies: The Zoning Administrator decides. § 9-5.2402 · code text A predominant portion of the area has slopes in excess of 10%; Hillside rules apply where a significant area has slopes of 25% or more. Applies: The Zoning Administrator decides. § 9-5.2402 · code text A significant area of slopes of 25% or greater are located in the area;

Who this affects

HomeownersContractorsDesigners

Frequently asked questions

What extra rules apply to a hillside lot in Antioch?

Antioch's code: Hillside rules apply where most of the area has slopes over 10%. (The Zoning Administrator decides.) (§ 9-5.2402); No grading unless it is specifically shown on an approved final development plan. (Parcels in hillside areas covered by the hillside article.) (§ 9-5.2408).

Building on a hillside in Antioch

What Antioch's code says

Who this affects

Frequently asked questions

Ask about a specific Antioch property

More on building on your lot in Antioch