Mold Remediation in Sonoma, CA
In Sonoma and the Valley, mold questions often lead back to two kinds of houses: older homes near the Plaza and homes rebuilt after the 2017 Nuns Fire. Santa Rosa Mold Pros is a free quote service that connects you with independent companies working here.
Get a Free QuoteHistory on one side, rebuilds on the other
The city of Sonoma, about 17 miles southeast of Santa Rosa, CA, grew around a Plaza laid out in 1835 and Mission San Francisco Solano, founded in 1823. Its 10,537 residents (July 2025 Census estimate) live in some of the older housing in the county: median year built 1977, with 56.7% of homes built before 1980 and 65.0% owner-occupied (ACS 2024 5-year).
In October 2017 the Nuns Fire, centered east and north of the city, destroyed 1,355 structures and merged with the Oakmont fire. Much of the Valley was rebuilt in the years after, often straight through wet winters. Sonoma Creek, the Valley's main watercourse, and about 29 inches of rain a year do the rest.
Why a rebuilt home can still grow mold
Wet framing closed in
Lumber and slabs rained on during construction, then covered before they dried.
New details, new leaks
A window corner or flashing seam that lets water into a wall with no stain yet.
First-decade plumbing
Fittings, valves and appliance hookups that fail slowly in the first years.
Survivors next door
Homes beside burned lots that took on firefighting water and were cleaned for smoke without opening wet walls.
None of this means a rebuilt house is unsound. It means a musty smell in a newer Valley home deserves a moisture check, not an air freshener. The fire-rebuild moisture page goes deeper.
Smoke cleanup and mold remediation are different jobs
| Smoke cleanup | Mold remediation | |
|---|---|---|
| What it addresses | Soot and odor on surfaces, contents and ducts | Growth fed by moisture in walls, floors, attics or crawl spaces |
| Typical insurance treatment (CDI) | Typically covered | Generally not covered |
| First step | Assessment of smoke residue | Finding and stopping the water |
Many restoration firms do both, but each needs its own written scope. Your policy decides what is paid, so never assume coverage. If walls or floors must be rebuilt afterward, that work usually needs a permit and a CSLB-licensed contractor. Start with a moisture inspection if the source is unclear, or read how mold removal usually works.
Contract protections after a declared disaster
Fires and floods have brought state and federal disaster declarations to Sonoma County, and with them door-to-door contractors. California law generally gives you seven days to cancel a contract to repair damage from a declared disaster, caps the down payment at $1,000 or 10% of the price, whichever is less, and makes unlicensed disaster-repair work a crime. Check any license on CSLB's lookup before signing.
Older homes near the Plaza raise a different question. Before drywall or plaster comes out of a pre-1980 house, ask about an asbestos survey, and for pre-1978 paint ask whether the company is EPA Lead-Safe Certified. The City of Sonoma runs its own building department.
Published estimates, not quotes: a typical whole job runs $1,500–$9,000 (Fixr 2025). Sonoma quotes come from the companies; see the cost guide.
Sonoma Valley mold questions
Our Glen Ellen home was rebuilt after the Nuns Fire. Why does it smell musty?
A rebuilt home can trap construction moisture, and new windows, flashing or plumbing can leak in their first years. Because Glen Ellen is unincorporated, any repair work goes through Permit Sonoma. Start with a moisture inspection that finds the water source; cleaning without fixing the leak usually means the smell comes back.
Will insurance pay for mold after fire damage?
It depends on the policy and the cause. The California Department of Insurance says smoke damage is typically covered and mold is generally not. Sudden and accidental water damage is typically treated differently from a slow, continuous leak. Ask your insurer in writing what applies to your claim. Nobody can promise coverage.
Can I get quotes in Kenwood or Boyes Hot Springs?
Yes. Requests from across the Sonoma Valley, including Kenwood, Glen Ellen and Boyes Hot Springs, go to independent companies that say they serve the area. Those unincorporated communities use Permit Sonoma, while the City of Sonoma has its own building department. Name your community in the form so companies can plan the trip.
Nearby towns and services
Get Sonoma Valley mold quotes
Say whether the house is original or rebuilt, which community it is in, and what you have noticed. Independent companies that work in the Valley reply to you directly. Prefer a call? (707) 896-6015
Seeing or smelling mold? Get a clear plan.
Free, no-pressure quotes from independent companies across Santa Rosa, Petaluma, Rohnert Park, Windsor and Sonoma County.