Windsor General Contractor
Windsor's housing stock is newer than most of Sonoma County, which changes what projects make sense here. Most of our work in town is additions, ADUs and second-generation remodels rather than deep structural repair.
Quick Answer
Howard Construction Inc. is a family-owned Class B general contractor serving Windsor, California, CSLB license #836369, based nearby in Santa Rosa and building across Sonoma County since 2000.
We build home additions, ADUs, kitchen and bathroom remodels, decks and custom homes throughout Windsor. Owner Philip Howard is on every job site. Free written estimates: (707) 578-6565.
What building in Windsor involves
Much of Windsor was built from the 1990s onward, which means the framing, wiring and plumbing are generally sound and current. The projects that make sense here are different from those in older parts of the county:
- Additions. Family homes on reasonable lots, where growing into the house beats moving. $350–$700 per square foot.
- ADUs and garage conversions. Strong demand for multigenerational living and rental income. Garage conversions run $120,000–$220,000, and state law forbids the Town requiring replacement parking.
- First-cycle remodels. Kitchens and baths from the 1990s and 2000s now reaching the end of their finish life.
- Outdoor living. Decks, pergolas, outdoor kitchens and pools, which the lot sizes here accommodate well.
Local conditions
- Expansive clay across much of the valley floor, which foundations must be engineered for.
- WUI fire zones on the eastern and northern edges toward Shiloh and the hills, triggering Chapter 7A requirements. The 2019 Kincade Fire evacuation made this concrete for many Windsor owners.
- Larkfield-Wikiup carries Santa Rosa-area addresses but is unincorporated, reviewed by Permit Sonoma rather than any town or city.
Windsor is a Town, not a City, and it runs its own building department. Review typically takes 4 to 8 weeks. Being a smaller department, a complete and well-prepared submittal moves noticeably faster than an incomplete one.
What we build in Windsor
| Service | 2026 range | Guide |
|---|---|---|
| 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 → |
| Custom homes | $400–$850/sq ft | Custom home building → |
Frequently Asked Questions
Who issues building permits in Windsor CA?
The Town of Windsor runs its own building department and issues permits inside town limits, with review typically taking 4 to 8 weeks. Nearby Larkfield-Wikiup and other unincorporated areas are reviewed by Permit Sonoma instead, on a different fee schedule and timeline.
How much does a home addition cost in Windsor?
Home additions in Windsor run $350 to $700 per square foot in 2026, so a 400 square foot addition typically costs $140,000 to $280,000. Ground-floor additions sit at the lower end and second-story additions at the higher end, because the existing foundation must be verified and often reinforced.
Can I convert my Windsor garage into an ADU?
Yes. California law requires ministerial approval of compliant ADU applications and explicitly prohibits the Town from requiring replacement parking when a garage is converted. Garage conversions run $120,000 to $220,000. The main technical issues are the existing slab, which is usually uninsulated and sloped to drain, and ceiling height.
Is Windsor in a fire zone?
Parts of Windsor, particularly on the eastern and northern edges toward Shiloh and the hills, fall within mapped Wildland-Urban Interface areas that trigger California Building Code Chapter 7A requirements: Class A roof assemblies, ember-resistant vents, ignition-resistant siding and decking restrictions near the structure. Whether your specific parcel is affected is confirmed during the site visit.
Related
Adding on in Windsor?
Phil will check your setbacks, lot coverage and whether your parcel is in a fire zone, then give you a written line-item estimate. Free and no obligation.
Get Your Free Estimate →