Lot Coverage Limits: Altadena vs Long Beach
How do lot coverage limits rules compare between Altadena, CA and Long Beach, CA?
Altadena and Long Beach have similar restriction levels.
Altadena, CA
Los Angeles County
Altadena R-1 max Gross Structural Area (GSA) and lot coverage = (0.25 × net lot area) + 1,000 sq ft, never exceeding 9,000 sq ft total (Altadena CSD 22.306.070.A.4).
View full Altadena rules →Long Beach, CA
Los Angeles County
Lot coverage in Long Beach varies by zoning district under LBMC Title 21 Chapter 21.31. R-1 zones typically allow 50-60% lot coverage. ADUs and accessory structures count toward total coverage.
View full Long Beach rules →Key Facts Comparison
| Fact | Altadena | Long Beach |
|---|---|---|
| Code Section | Altadena CSD 22.306.070.A.4 | - |
| GSA Formula | 0.25 × lot area + 1,000 sf | - |
| Maximum Cap | 9,000 sq ft | - |
| Excluded From GSA | Cellars + auto garages/carports | - |
| R-1 Zone | - | Typically 50-60% max |
| Code | - | LBMC Title 21, Ch. 21.31 |
| ADUs | - | Count toward coverage |
| Accessory Structures | - | Included in calculation |
Highlighted rows indicate differences between cities.
Altadena FAQ
How big a house can I build on a 10,000-sq-ft Altadena lot?
Maximum GSA = 0.25 × 10,000 + 1,000 = 3,500 sq ft (excluding garage and cellar). The absolute cap is 9,000 sq ft on any lot.
Long Beach FAQ
What counts as lot coverage?
All impervious surfaces: buildings, garages, driveways, patios, and walkways. Permeable pavers may be partially excluded.
How do I calculate my lot coverage?
Divide total impervious surface area by total lot area. Check Long Beach zoning for your district’s maximum.
Compare other topics
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