HPOZ Rules: Castaic vs Los Angeles
How do hpoz rules rules compare between Castaic, CA and Los Angeles, CA?
Castaic has fewer restrictions than Los Angeles.
Castaic, CA
Los Angeles County
Los Angeles County does not use Historic Preservation Overlay Zones; unincorporated areas instead apply Significant Ecological Areas under Title 22.110.060 for natural resources and Mills Act historic districts for buildings.
View full Castaic rules →Los Angeles, CA
Los Angeles County
LAMC Section 12.20.3 establishes Historic Preservation Overlay Zones. Los Angeles has 35-plus HPOZs (Highland Park, Spaulding Square, Angelino Heights, others) where an HPOZ Board must review any visible exterior alteration, demolition, or new construction.
View full Los Angeles rules →Key Facts Comparison
| Fact | Castaic | Los Angeles |
|---|---|---|
| City HPOZ tool | Not used by county | - |
| SEA authority | LACO Title 22.110.060 | - |
| Historic authority | LACO Title 22.124 | - |
| SEAs cover | Santa Monica Mountains, Antelope Valley | - |
| Tax incentive | Mills Act contracts | - |
| Code section | - | LAMC Section 12.20.3 |
| Districts | - | 35-plus citywide |
| Trigger | - | Visible exterior changes |
| Approval | - | Certificate of Appropriateness |
| Staff agency | - | Office of Historic Resources |
Highlighted rows indicate differences between cities.
Castaic FAQ
Is there an HPOZ in unincorporated LA County?
No. HPOZ is a Los Angeles City zoning overlay. The county relies on Significant Ecological Areas under Title 22.110.060 and historic districts under Title 22.124 for similar protective purposes.
How do I get historic protection for a building in Altadena?
Apply for Mills Act designation or county Historical Landmark status through the Department of Regional Planning. The Historical Landmarks Commission reviews and recommends action to the Board of Supervisors.
Los Angeles FAQ
Does HPOZ review apply to interior remodels?
No. HPOZ jurisdiction covers exterior features visible from the public right-of-way. Interior alterations need only standard building permits and do not require Certificate of Appropriateness review.
How long does HPOZ review take?
Conforming work approved at staff level typically clears in two to four weeks. Projects requiring full HPOZ Board hearings (additions, demolitions, new construction) commonly take 60 to 120 days.
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