Showing ordinances that apply to Port Costa, CA
Port Costa is an unincorporated community (population 190) in Contra Costa County, California. Because Port Costa is not an incorporated city, it does not have its own municipal code. Instead, Contra Costa County ordinances apply directly to properties here. The occupancy limits rules below are the ones that govern your area.
Contra Costa County does not set a county-wide explicit per-night occupancy cap for STRs, but general building code occupancy standards apply. Uniform Housing Code and California Building Code limit occupants based on bedroom count and square footage, typically 2 per bedroom plus 2 additional guests.
Unincorporated Contra Costa County does not have a dedicated STR ordinance establishing specific occupancy caps (e.g., 2 per bedroom), but the California Building Code and the county's adopted Housing Code place enforceable limits on how many people can lawfully occupy a dwelling. Under standard building code provisions, bedrooms must be at least 70 square feet for the first occupant and 50 additional square feet for each additional occupant. A common rule of thumb applied by insurers and platforms is 2 guests per bedroom plus 2 additional guests (e.g., a 3-bedroom home would accommodate 8). STR operators are also subject to noise, parking, and nuisance ordinances; exceeding reasonable occupancy can trigger code enforcement under Chapter 710-10 nuisance provisions or Chapter 716-8 noise rules. Septic system capacity is a practical limiter in rural unincorporated areas (Marsh Creek, Byron, Tassajara), where undersized systems cannot handle peak loads. Events, parties, and gatherings exceeding typical residential occupancy may require a temporary event permit and can be restricted by community plan policies.
Contact your local code enforcement office for specific penalty information.
See how Port Costa's occupancy limits rules stack up against other locations.
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