Building on a hillside in El Cajon: the local rules

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

What El Cajon's code says

El Cajon code What El Cajon's code adds
Soils or geology report	A detailed geotechnical report by a certified engineering geologist or licensed geotechnical engineer is required. Applies: Hillside development proposals, including retaining walls in areas of known geological hazards. § 17.170.070 · code text All proposals for development, including proposals for retaining walls in areas of known geological hazards, shall be accompanied by a detailed geotechnical report prepared by a certified engineering geologist or licensed geotechnical engineer
Grading and retaining walls	No steeper than 2:1, which is 2 horizontal to 1 vertical. Applies: Cut and fill slopes. § 17.170.040 · code text Cut and fill slopes shall be constructed at a gradient ratio no steeper than two horizontal to one vertical (2:1). At most 30 feet, measured vertically. Applies: Any cut or fill slope, or both combined. § 17.170.040 · code text No cut or fill slope or combination thereof shall exceed the height of 30 feet measured vertically. Such slopes must be separated by a building pad, a street or at least 30 feet of natural slope. Applies: Cut and fill slopes higher than 15 feet. § 17.170.040 · code text Cut and fill slopes with a height greater than 15 feet shall be separated by a building pad, a street, or, if a natural slope separation is used, a minimum distance of 30 feet. Natural ground may not be lowered or raised more than 30 feet. § 17.170.040 · code text The elevation of the natural terrain shall not be lowered or raised by more than 30 feet. At least 90% of maximum density, unless the city engineer requires more. Applies: Compaction of fill material. § 17.170.040 · code text The density of all fill material shall be compacted to no less than 90 percent of maximum density, unless the city engineer requires a more dense compaction. Hillside grading rules do not apply to an excavation of 50 cubic yards or less and under 1 foot deep. Applies: Exemption. § 17.170.080 · code text An excavation that does not exceed 50 cubic yards and is less than one foot in vertical depth; Hillside grading rules exempt embankments of 50 cubic yards or less, under 1 foot high, that do not block drainage. Applies: Exemption. § 17.170.080 · code text An embankment that does not exceed 50 cubic yards, is less than one foot in vertical height, and does not obstruct a drainage course;

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Frequently asked questions

What extra rules apply to a hillside lot in El Cajon?

Hillside cut and fill slopes can be no steeper than 2:1 and no more than 30 feet high.

Building on a hillside in El Cajon

Key points

What El Cajon's code says

Who this affects

Frequently asked questions

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