Thousand Oaks, CA Zoning Overlays & Bonuses: Hillside Overlay Rules (2026)
Key Facts
- Zone
- H-P-D (Hillside Planned Development)
- Applies to slopes averaging
- 10% or greater
- Density on 35%+ slope
- 0.1 units/acre
- Density on 10–14.9% slope
- 2.0 units/acre
- Max density via transfer
- 7 units/net acre
Summary
In Thousand Oaks's Hillside Planned Development (H-P-D) zone, how many homes can be built per acre depends directly on how steep the land is: the steeper the slope, the fewer units allowed, dropping to just 0.1 units per acre on slopes over 35%. The city caps hillside density at a maximum of seven units per net acre even with a density transfer.
No more than seven (7) units shall be permitted on any one net acre through a density transfer in the H-P-D Zone. The density for property within an H-P-D Zone shall depend on the average slope of the natural terrain of the area within the proposed development... The density for property within this zone shall be computed in accordance with the following scale: Average Percent of Slopes: 10–14.9% / Maximum Density: 2.0 D/U per Gross Acre; 15–19.9% / 1.6; 20–24.9% / 1.2; 25–29.9% / .8; 30–34.9% / .4; 35% and over / .1.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-78: 2026 S-78 Supplement contains: Current city legislation passed through March 31, 2026).
Full Breakdown
The H-P-D zone applies to hillside areas with an average natural slope of 10% or more (Sec. 9-4.3101), and density there is not a flat number: it's computed off a sliding scale tied to the site's average percent slope, calculated from a topographic survey submitted with the permit application. Density ranges from 2.0 dwelling units per gross acre on gentler 10–14.9% slopes down to just 0.1 units per acre on slopes of 35% or greater. For unique properties under 10% average slope within an H-P-D zone, the Council may allow up to 4.0 units per gross acre. Older recorded parcels (pre-Sept. 9, 1971) on slopes of 24.9% or steeper are guaranteed at least one dwelling unit.
Violations & Fines
Development inconsistent with the calculated density, or grading/construction without an approved H-P-D permit, is processed under the zoning chapter's general enforcement provisions (TOMC §§ 9-4.3005–9-4.3007): unauthorized building or use is declared a public nuisance subject to abatement, and the Community Development Director may issue a stop-work order.
Frequently Asked Questions
How is "average slope" calculated for my property?
Can I build more units than the slope table allows?
Sources & Official References
Other rules in Thousand Oaks
California rules heatmap·Compare Thousand Oaks to another location·View the California zoning overlays & bonuses overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.