Lot Coverage Limits: Altadena vs Compton
How do lot coverage limits rules compare between Altadena, CA and Compton, CA?
Altadena and Compton 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 →Compton, CA
Los Angeles County
Lot coverage requirements vary by zoning district under Compton's Chapter 30 zoning code. ADUs must conform to lot coverage and open space requirements for the zone, except where applying those rules would prevent building an 800 sq ft ADU with 4 ft setbacks per state law.
View full Compton rules →Key Facts Comparison
| Fact | Altadena | Compton |
|---|---|---|
| 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 | - |
| Residential | - | Varies by zone (R-L, R-M, R-H) |
| ADU Exception | - | 800 sq ft minimum guaranteed by state |
| Open Space | - | Required per zoning district |
| Reference | - | CMC Chapter 30 |
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.
Compton 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 Compton zoning for your district’s maximum.
Compare other topics
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