Windsor
Sonoma County, California
Last verified September 16, 2026
Windsor is a jurisdiction in Sonoma County, California, with an online portal for searching and pulling active or historical building permits. Use the contact information below to reach the local building department, or the mailing address if the jurisdiction needs to be listed as a certificate holder on a contractor's insurance documentation.
Contact
- Phone
- 707-836-2304
- buildingpermits@townofwindsor.ca.gov
- Department Site
- Building Division (opens in a new tab)
Permit Search
Certificate Holder Mailing Address
Town of Windsor Building Division9291 Old Redwood Highway, Suite 400 (P.O. Box 100)
Windsor, CA 95492
Use this address when the jurisdiction needs to be listed as a certificate holder on a contractor's insurance documentation.
Additional Notes
Counter hours Monday-Thursday 8am-11am or by appointment. Domain-collision note: Windsor already exists in this directory for Connecticut and Vermont - this entry is Windsor, CA (Sonoma County).
What You Need Before Applying for a Permit
Most building departments ask for the same core package before they'll issue a permit: a completed application naming the property owner and contractor, the contractor's state license number and proof of insurance (general liability, and workers' comp if employees are on the job), a notice of commencement or equivalent recorded filing for larger jobs where the state requires one, and scaled plans or a site plan for anything beyond minor repairs. Roofing, fence, pool, and solar permits typically have their own simplified checklists — Windsor's department (above) can confirm exactly what applies to your project.
Why this matters for insurance: permit history is one of the first things an underwriter or adjuster checks. Unpermitted work — a finished basement, an added bedroom, a rebuilt roof — can complicate a claim or even void coverage for that portion of the loss, and it routinely surfaces during a home inspection. Pulling the right permit up front, and keeping the closed-permit record on file, protects both the property's value and its insurability at resale.
More in Sonoma County
See Sonoma County property and court records →
Other building permit jurisdictions in Sonoma County: