City and agency directory
Contra Costa's directory pairs city contacts with CCMAP jurisdiction research. Start here to determine whether County planning or a city is the correct land-use authority; the mailing address alone is not enough.
California county resources
Manufactured homes in Contra Costa County
Net Cost serves Contra Costa County. Use these local resources to investigate the parcel before choosing a home. Delivery, installation scope and project feasibility need a site-specific review.
Local research
Identify the city before choosing the permit desk
Building or grading permit overview
The permit overview distinguishes unincorporated planning approval, city planning approvals and other clearances. It also calls out Environmental Health review for wells or septic systems. Ask which clearances belong in your specific application package.
Resources checked October 20, 2026. These official resources are research starting points. Confirm current requirements with the responsible agency for your parcel and project.
Official permit and application resources
Building permit applications
Issuing agency: Contra Costa County Department of Conservation and Development — Building Division
Purpose: Identify the appropriate county building application and required documents; follow the official digital-submittal guidance.
Jurisdiction: County resource. Confirm County authority for an unincorporated parcel; for incorporated-city parcels, begin with the city and verify any contracted County review. Park installation authority must be checked separately through HCD or the authorized local enforcement agency.
Link checked October 20, 2026. Use the agency’s current forms and instructions. Confirm the required application category, form revision, supporting plans and inspection steps with that agency. These are outgoing official links; Net Cost does not host the forms. A listed resource does not establish parcel eligibility, a complete submittal or permit approval.
Confirm who reviews the project
First establish whether the parcel is inside an incorporated city or in the unincorporated county. For a city parcel, begin with the city’s planning department and confirm its building authority; some cities contract building review to the county or another agency. For an unincorporated parcel, begin with County Planning and Building. A postal city name does not determine jurisdiction.
Park placement follows a separate enforcement route: use HCD’s local enforcement agency guidance and confirm park-management requirements. For water, sewer, wells or septic, identify the actual provider and reviewing agency; county geography does not establish a utility service boundary.
Serving this county does not mean every parcel qualifies. Read the shared site-planning checklist for utility checks and the information needed to compare complete project estimates.
Plan your project
Discuss your site in Contra Costa County
Share the parcel and intended use so we can discuss the home and the work needed for your site.