Lot Coverage Limits: Castro Valley vs Fremont
How do lot coverage limits rules compare between Castro Valley, CA and Fremont, CA?
Castro Valley and Fremont have similar restriction levels.
Castro Valley, CA
Alameda County
Unincorporated Alameda County limits maximum lot coverage to 35-45 percent in residential zones under Title 17. Coverage includes all structures with roofs, with some exemptions for uncovered decks and pervious surfaces.
View full Castro Valley rules →Fremont, CA
Alameda County
Fremont generally limits lot coverage in R-1 zones to 40 percent for the primary structure, with total coverage including accessory buildings capped at 50 percent.
View full Fremont rules →Key Facts Comparison
| Fact | Castro Valley | Fremont |
|---|---|---|
| Typical R-1 coverage | 40 percent maximum | - |
| Hillside zones | Often 35 percent | - |
| Uncovered decks | Under 30 inches exempt | - |
| ADU exception | 800 sf exempt per state law | - |
| FAR overlay | Applies in hillside districts | - |
| Main Coverage | - | 40 percent typical |
| Total Coverage | - | 50 percent typical |
| FAR | - | 0.45 to 0.50 |
| ADU Exemption | - | Per state law |
| Contact | - | (510) 494-4455 |
Highlighted rows indicate differences between cities.
Castro Valley FAQ
Does my driveway count toward lot coverage?
No. Driveways and paved walkways are not structures. However, some zones have separate impervious surface limits that include paving.
How do I find my coverage limit?
Check your zoning designation on the Alameda County Planning parcel map, then reference Title 17 for that specific zone.
Fremont FAQ
Does my patio count toward lot coverage?
At-grade patios usually do not count; covered patios, pergolas, and carports typically do.
Can I exceed FAR with an ADU?
Yes, state law exempts ADUs up to 800 square feet from lot coverage and FAR limits.
Compare other topics
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