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Golden Ridge Construction is a licensed general contractor (License #1149928) serving Contra Costa County, California, in Contra Costa County. We handle kitchen and bathroom remodels, ADUs, home additions, and whole-home remodels across Contra Costa County.
These are planning ranges for typical 2026 projects, not quotes. Every project is priced after a site visit.
Construction and remodeling in Contra Costa County splits roughly along the hills. Walnut Creek, Concord and Pleasant Hill filled in heavily through the post-war decades with conventional, predictable housing. Lafayette, Orinda and Moraga run older in places and sit on slopes, and Danville, Alamo and San Ramon carry larger lots with more room to add.
Richmond and El Cerrito on the western side are a different market again, with pre-war stock closer in age and character to Berkeley and Albany than to the valley.
There is no single Contra Costa County building permit process. Walnut Creek, Concord, Richmond and the other cities each run their own department, while the unincorporated communities — Alamo, Kensington, El Sobrante, Pacheco, Rodeo, North Richmond, Discovery Bay and others — permit through the County's Department of Conservation and Development.
One County rule is worth knowing before you draw a bathroom: in unincorporated Contra Costa, the permit trigger for a bathroom remodel is replacing the tub or shower enclosure. Keep the enclosure and much of the rest is finish work; replace it and you are in permit territory with the code requirements that come along with it.
Permit fees and review times change. Check current requirements on the Contra Costa County Department of Conservation and Development building permits page before planning around a date.
In post-war valley homes, opening the kitchen to the living space is the change that most transforms the plan, and it is structural work because that wall is usually load-bearing. Adding a second bathroom inside the existing footprint is the next most useful.
In the hill towns, grade drives everything. Stepped foundations, retaining, access for materials and drainage all cost more than the same project on a flat lot, and drainage in particular is worth designing rather than improvising.
Alamo, Kensington, El Sobrante, Pacheco, Rodeo, North Richmond, Tara Hills, Diablo and Discovery Bay are not inside any city. Those properties permit through the County's Department of Conservation and Development, which takes applications through its online ePermit Center or at its Martinez counter.
The County also runs a pre-approved ADU plan program for its unincorporated service area, where plans are reviewed and approved in advance so an applicant using one gets a more streamlined review. It does not remove site-specific review — you still need planning review, a site plan and foundation design for your particular parcel — but it takes the building code review off the critical path.
Converted garages and back units that were never permitted turn up regularly here, particularly in the older western county. Since January 2025, California's AB 2533 has offered an amnesty path for ADUs and junior ADUs built without permits before January 1, 2020.
A local agency cannot deny that permit purely because the unit fails current building code, unless the issue is a genuine health or safety hazard, and no impact fees or utility connection charges apply unless upgrades are needed for safety. Our [garage conversion guide](/projects/garage-conversion-bay-area-options) covers what the work involves.
State law sets the floor in every city: ministerial review within 60 days for designs meeting objective standards, and no owner-occupancy requirement since 2024. The larger lots in Danville, Alamo, San Ramon and parts of Walnut Creek take a detached unit comfortably.
On hillside parcels in Lafayette, Orinda and Moraga, converting existing lower-level space is often better value than new detached construction, because slope adds foundation and access cost before you have built anything.
Call (408) 418-8376 or visit our contact page for a free, no-obligation estimate, explore our services, and see all service areas we cover.