One county, twelve permitting jurisdictions, and building conditions that change from the Petaluma flats to the Cloverdale hills. We have built across all of it since 2000.
Howard Construction Inc. is a family-owned Class B general contractor serving all of Sonoma County, California, CSLB license #836369, headquartered in Santa Rosa and building continuously since 2000.
We build custom homes, additions, ADUs, kitchen and bathroom remodels, decks and pools from Petaluma to Cloverdale, and from Sebastopol to Sonoma Valley. Owner Philip Howard is on every job site. Free written estimates. Call (707) 578-6565.
Countywide. In practice most of our work concentrates in the central and southern county, within reasonable reach of Santa Rosa:
We also build across the county line in Napa County and Marin County. See all service areas.
This is the question that most affects your timeline, and the answer is not obvious from your mailing address. Sonoma County contains nine incorporated cities plus a large unincorporated area, and each runs its own process.
| Jurisdiction | Reviews | Typical timeline |
|---|---|---|
| City of Santa Rosa | Inside city limits only | 3–8 weeks |
| City of Petaluma | Inside city limits | 4–9 weeks |
| City of Healdsburg | Inside city limits; design review downtown | 4–10 weeks |
| City of Sebastopol | Inside city limits | 4–9 weeks |
| Town of Windsor | Inside town limits | 4–8 weeks |
| Rohnert Park / Cotati / Cloverdale / Sonoma | Inside respective limits | 4–10 weeks |
| Permit Sonoma (unincorporated) | Everywhere else in the county | 4–12 weeks |
A mailing address is not a jurisdiction. Larkfield-Wikiup, Mark West, Bennett Valley, Penngrove, Glen Ellen, Kenwood, Forestville and Guerneville all carry city-style mailing addresses but are unincorporated — Permit Sonoma reviews them, often with septic and fire-access review layered on top. Confirming this before design begins routinely saves a month.
Full detail in our Sonoma & Napa County permit guide.
Since 2017, wildfire has reshaped how this county builds. Large areas are mapped Wildland-Urban Interface, which triggers California Building Code Chapter 7A: Class A roof assemblies, ember-resistant vents, ignition-resistant siding and soffits, enclosed eaves, and decking restrictions within ten feet of the structure. Expect $25,000–$70,000 on new construction in a WUI zone.
This is no longer only a code question. Insurance carriers increasingly price — or decline — coverage based on these exact features, so a compliant build affects whether the home is insurable at all.
Expansive clay is widespread across the Santa Rosa plain and the Petaluma and Cotati valleys. It swells when wet and shrinks when dry, and foundations must be engineered for it. Hillside areas — Fountaingrove, Bennett Valley, the Sonoma Mountain and Mayacamas slopes — add slope stability, drainage and often drilled piers.
A large share of unincorporated parcels run on well and septic. Adding a bedroom typically triggers an Environmental Health evaluation and sometimes an expanded leach field, $15,000–$55,000. This should be established early, not after design.
Properties along the Russian River, Laguna de Santa Rosa and Petaluma River may fall in mapped floodplain, bringing elevation requirements and flood-resistant construction standards.
Much of the county protects native oaks. Removal or significant work within the dripline may require a permit and mitigation planting.
| Service | Typical 2026 range | Guide |
|---|---|---|
| Custom homes | $400–$850/sq ft | Read → |
| Home additions | $350–$700/sq ft | Read → |
| ADUs | $180,000–$420,000 | Read → |
| Garage conversions | $120,000–$220,000 | Read → |
| Kitchen remodels | $45,000–$180,000 | Read → |
| Decks & pergolas | $45–$110/sq ft | Read → |
| Swimming pools | $65,000–$220,000 | Read → |
| Lindal post-and-beam homes | Package + build | Read → |
Four checks, in order, before price enters the conversation:
Our full breakdown, including ten red flags and twenty questions worth asking, is in how to hire a contractor in California. It applies to any contractor you are considering, including us.
Rather than relying on a ranked list, verify each candidate directly: check the CSLB license at cslb.ca.gov for active status and Class B classification, confirm general liability and workers' compensation insurance, review ratings on Google and Houzz, and call local references on projects of comparable scope. Howard Construction Inc. is a family-owned Class B general contractor, CSLB #836369, headquartered in Santa Rosa and building throughout Sonoma County since 2000.
Custom home construction in Sonoma County runs $400 to $850 per square foot in 2026, excluding land. A 2,200 square foot home typically costs $900,000 to $1.87M in hard construction cost. Site work, permits and impact fees are additional, and homes in Wildland-Urban Interface zones add $25,000 to $70,000 for Chapter 7A fire-hardening requirements.
It depends on whether the property is inside an incorporated city or in unincorporated county. The cities of Santa Rosa, Petaluma, Healdsburg, Sebastopol, Sonoma, Rohnert Park, Cotati and Cloverdale and the Town of Windsor each issue their own permits. Everywhere else is Permit Sonoma. Many properties with city mailing addresses, including Larkfield-Wikiup, Penngrove, Glen Ellen and Forestville, are actually unincorporated.
If your property is in a mapped Wildland-Urban Interface zone or State Responsibility Area, California Building Code Chapter 7A applies. That requires a Class A roof assembly, ember-resistant vents, ignition-resistant exterior siding and soffits, enclosed eaves, dual-pane windows with tempered glass, and decking restrictions within ten feet of the structure. Budget $25,000 to $70,000 on new construction.
In most cases yes. California law requires ministerial approval of compliant ADU applications with no public hearing, obligates the agency to decide within 60 days, and prohibits requiring replacement parking for garage conversions. Local constraints that still apply in Sonoma County include septic capacity, fire apparatus access on rural parcels, and floodplain rules. Detached ADUs cost $180,000 to $420,000 and garage conversions $120,000 to $220,000.
Yes. We build throughout Sonoma County including Santa Rosa, Petaluma, Sebastopol, Healdsburg, Windsor, Rohnert Park, Cotati, Sonoma, Glen Ellen, Kenwood, Forestville, Occidental, Guerneville and Cloverdale, and also work in Napa and Marin counties. Our office is at Santa Rosa, California, and the phone number is (707) 578-6565.
From Petaluma to Cloverdale, Phil will walk your property, confirm your permitting jurisdiction, and give you a written line-item estimate. Free and no obligation.
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