General Contractor in Ventura County: Thousand Oaks, Simi Valley and the Coast
Green Design and Build is a licensed residential general contractor (CSLB #1110975) that remodels and builds homes across Ventura County: kitchens, bathrooms, ADUs, room additions, whole-home renovations, roof replacement and outdoor living in Thousand Oaks, Simi Valley, Moorpark, Camarillo, Oxnard, Port Hueneme and Ventura. The company is led by Dekel Sofer, serving homeowners across Los Angeles County, Orange County, Ventura County, western Riverside County and western San Bernardino County from our office in Van Nuys. The Conejo Valley and Simi Valley are 30 to 45 minutes from that office; an ADU here takes six months to a year from first meeting to final inspection, a bathroom a few weeks, and a kitchen a few months.
How we serve Ventura County from Van Nuys
Our office is at 16120 Sherman Way in Van Nuys. We do not have a Ventura County office; what we have is a short drive: Thousand Oaks, Newbury Park, Westlake and Agoura Hills are 30 to 45 minutes west on the 101, and Simi Valley and Moorpark are about the same on the 118. Camarillo is closer to an hour, Oxnard and Ventura an hour to an hour and a quarter depending on traffic. We do not currently take projects in Ojai, Santa Paula or Fillmore.
Site visits are scheduled in clusters, with Conejo Valley and Simi Valley appointments grouped on the same day. Once a project starts, the crew assigned to it is on site every working day until it is finished, and inspections are called in by the project lead who is already there. Design, permits and construction are handled in house, with a detailed written estimate before work begins. HVAC, plumbing, electrical, roofing (C-39) and asbestos work are performed by our licensed specialty-trade partners under our supervision.
Who issues the permit in Ventura County
Ventura County has ten incorporated cities, and each runs its own building department. Thousand Oaks, Simi Valley, Moorpark, Camarillo, Oxnard, Ventura and Port Hueneme each issue their own residential permits, each with its own checklist and plan-check timeline. Everything outside city limits is handled by Ventura County Building and Safety, which covers Oak Park, Santa Rosa Valley, Somis, Hidden Valley, Bell Canyon and the other unincorporated communities.
The Conejo Valley is where this gets confusing, because the county line runs through it.
| Community | County | Who issues the building permit |
|---|---|---|
| Thousand Oaks, Newbury Park, and the Westlake and North Ranch neighborhoods inside Thousand Oaks | Ventura | City of Thousand Oaks |
| City of Westlake Village | Los Angeles | City of Westlake Village |
| Agoura Hills, Calabasas, Hidden Hills | Los Angeles | Each city’s own building department |
| Oak Park, Bell Canyon, Santa Rosa Valley, Somis, Hidden Valley | Ventura (unincorporated) | Ventura County Building and Safety |
| Simi Valley, Moorpark, Camarillo, Oxnard, Ventura, Port Hueneme | Ventura | That city’s building department |
The City of Westlake Village sits on the Los Angeles County side of the line; the Westlake neighborhoods west of it, including North Ranch, are part of Thousand Oaks. Agoura Hills and Calabasas are Los Angeles County cities with their own departments, not LADBS. Oak Park is unincorporated Ventura County. We confirm jurisdiction from the parcel, not the mailing address, before we submit anything.
Two local rules come up often. Thousand Oaks protects oak trees by ordinance, so an addition, ADU or patio cover near the canopy or root zone of an oak needs a separate review and sometimes an arborist report. And homes on septic, common in Santa Rosa Valley, Somis and Hidden Valley, need the county to confirm capacity before an added bedroom or ADU is approved.
Fire zones and rebuilding: what Ventura County homeowners already know
Ventura County has been through two of the largest fires in modern California history. The Thomas Fire started near Santa Paula in December 2017 and burned through the hillsides above Ventura and the Ojai Valley, destroying more than a thousand structures. The Woolsey Fire started near Simi Valley in November 2018 and ran through Oak Park, Thousand Oaks, Westlake, Agoura Hills and Calabasas to the Malibu coast, destroying roughly 1,600 structures. In November 2024 the Mountain Fire burned through Camarillo Heights and Somis and took more than 200 homes.
The practical result is that a large share of Ventura County homes sit inside a Very High Fire Hazard Severity Zone, and any addition, ADU or re-roof there has to meet Chapter 7A of the California Building Code: Class A roofing, ember-resistant vents, ignition-resistant siding and decking, tempered glazing and defensible space. Rebuilds after a fire also have to meet current Title 24 and seismic standards even when the original house predated both. We build to 7A on any hillside or canyon lot in the county, mapped or not, because the fire does not check the map.
We have managed fire-damage roofing in Los Angeles County; Sagi L. wrote after the Altadena fire: “We had him come out for a full roofing job and not only was he extremely knowledgeable and quick, but his team was extremely professional.” Roofing on our projects is performed and permitted by a contractor holding an active C-39 classification, scheduled and supervised by Green Design and Build as the general contractor, and the same standard applies in Ventura County. See our roofing page and our note on re-roof permits, which covers the City of Los Angeles; Ventura County cities have their own equivalents.
The housing stock: 1970s–90s tracts, big lots and HOA communities
Most of Ventura County’s suburban housing was built between the late 1960s and the 1990s: Thousand Oaks and Newbury Park through the 1970s and 80s, Simi Valley from the 1960s to the 80s with Wood Ranch later, Moorpark and much of Camarillo in the 1980s and 90s. Ventura and Oxnard have older cores with 1920s to 1950s bungalows. What we find in these homes:
- Closed-off kitchens and formal dining rooms that owners want opened into one space. The dividing wall is often load-bearing, so a kitchen remodel here includes an engineered beam and a structural permit. Bathroom remodeling in the same houses is usually a tub-to-shower conversion or a primary bath enlarged into a closet.
- Original windows, insulation and roofing at the end of their life. Replacing them triggers Title 24, which we handle with the permit. Simi Valley and Moorpark summers are hot, so these upgrades pay back faster there than on the coast.
- Pre-1980 framing that was never seismically retrofitted. Simi Valley took heavy damage in the 1994 Northridge earthquake, and we still see unbolted sill plates and unbraced cripple walls, which we address as foundation and structural work when we open a house up.
- Lead paint and asbestos in anything built before 1978. We test first; abatement is done by our licensed partner.
The lots are the other difference. Ventura County lots run larger than San Fernando Valley lots, and in Santa Rosa Valley, Somis, Hidden Valley, Bridle Path in Simi Valley they are rural or equestrian, with barns, corrals, long driveways and room for a detached ADU well away from the main house. Those properties bring their own checklist: grading and drainage, septic capacity, fire access, and county rather than city review.
Westlake, North Ranch, Oak Park, Wood Ranch, Dos Vientos and Spanish Hills are HOA communities with architectural review committees. Anything visible from outside the house, including additions, ADUs, patio covers, windows, roofing and exterior color, needs committee approval before construction, and we file that package before the city or county permit so neither holds up the other. State law prevents an HOA from prohibiting an ADU, but it can apply reasonable design conditions.
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ADUs in Ventura County
California’s ADU law applies in every Ventura County city and in the unincorporated county. A compliant detached ADU (state law guarantees at least an 800-square-foot unit with 4-foot side and rear setbacks on any lot with a house), a junior ADU of up to 500 square feet inside the house, or a garage conversion must be approved ministerially, with a 60-day review clock on a complete application. Larger lots make detached units the common choice here, and on rural parcels the questions are septic capacity, fire access and utility runs rather than setbacks. Start with our ADU rules calculator, read how much an ADU costs for a real project budget, and see our ADU and garage conversion pages for what we build.
What we build most in Ventura County
- Kitchen remodeling and bathroom remodeling in 1970s–90s Conejo Valley and Simi Valley homes.
- ADUs and garage conversions on larger lots; see our Thousand Oaks ADU page.
- Room additions and whole-home renovations, including fire-zone rebuilds.
- Roof replacement: Class A re-roofs coordinated as your general contractor, often paired with solar installed by our licensed partner.
- Patio covers, pavers, outdoor living and backyard remodeling; compare patio cover materials and see our patio cover cost page.
- Concrete, retaining walls, artificial turf, fencing, outdoor kitchens and decks and landscaping and irrigation.
- Flooring, painting and windows and doors; the full list is on our services page.
Where we work in Ventura County
| Area | Communities | Notes |
|---|---|---|
| Conejo Valley | Thousand Oaks, Newbury Park, Westlake, North Ranch, Oak Park; Westlake Village, Agoura Hills and Calabasas on the LA County side | Closest to our office; HOA communities; oak tree ordinance |
| Simi Valley and Moorpark | Simi Valley, Wood Ranch, Bridle Path, Moorpark | 1960s–90s tracts; hot summers; equestrian lots |
| Camarillo and the Santa Rosa Valley | Camarillo, Camarillo Heights, Spanish Hills, Mission Oaks, Santa Rosa Valley, Somis | Larger lots; septic in rural areas; Mountain Fire rebuilds |
| Oxnard, Ventura and the coast | Oxnard, Port Hueneme, Ventura, Hollywood Beach, Silver Strand | Older housing; coastal-zone permits near the beach; hillside rebuilds in Ventura |
Why Ventura County homeowners hire Green Design and Build
- Licensed, bonded and insured, CSLB #1110975. Verify the license with the Contractors State License Board.
- 146 reviews on Yelp with a 4.7-star rating and hundreds of completed projects.
- Design, permits and construction under one contract, with a detailed written estimate before work begins.
- Structural, foundation and fire-zone work done by our own crews.
Troy S. described a roof rebuild on a 1969 house: “I worked with both Max and TOM to rebuild my roof. We added Solar a brand new electrical box and backup battery for a 1969 house. They were very responsive quick to recommend ideas.” Before you hire anyone, read our guide on how to hire a general contractor without getting scammed.
We also serve the San Fernando Valley, Los Angeles, Orange County, western Riverside County and western San Bernardino County. The full list of cities is on our service areas page.
Frequently asked questions about remodeling in Ventura County
Do you have an office in Thousand Oaks or elsewhere in Ventura County?
No. Green Design and Build works in Ventura County from its office in Van Nuys, 30 to 45 minutes from Thousand Oaks and Simi Valley. Site visits are grouped by area, and once a project starts the crew assigned to it is on site every working day until it is finished.
Who issues building permits in Ventura County?
Each of Ventura County’s ten cities, including Thousand Oaks, Simi Valley, Moorpark, Camarillo, Oxnard and Ventura, issues its own residential building permits through its own building department. Properties outside city limits, such as Oak Park, Santa Rosa Valley, Somis and Bell Canyon, are permitted by Ventura County Building and Safety.
Is Westlake Village in Ventura County, and does it matter for my permit?
The City of Westlake Village is in Los Angeles County and issues its own permits; the Westlake and North Ranch neighborhoods across the county line are part of Thousand Oaks in Ventura County. Agoura Hills and Calabasas are also Los Angeles County cities with their own building departments. Each office has its own forms, fees and plan-check timeline, so we verify which one applies to your parcel first.
Can I build an ADU in Thousand Oaks or Simi Valley?
Yes. California’s ADU law applies in Thousand Oaks, Simi Valley and every other Ventura County city, so a compliant detached ADU (state law guarantees at least an 800-square-foot unit with 4-foot side and rear setbacks on any lot with a house), a junior ADU of up to 500 square feet, or a garage conversion must be approved ministerially within 60 days of a complete application. HOAs and cities can apply reasonable design conditions but cannot prohibit the unit.
What extra rules apply if my Ventura County home is in a fire hazard zone?
A home in a Very High Fire Hazard Severity Zone in Ventura County must meet Chapter 7A of the California Building Code for any addition, ADU or re-roof: Class A roofing, ember-resistant vents, ignition-resistant siding and decking, tempered glazing and defensible space. Much of the Conejo Valley, Oak Park, Simi Valley’s hillsides, Camarillo Heights and the hills above Ventura and Ojai fall into these zones.
How long does a kitchen or bathroom remodel take in Ventura County?
A bathroom remodel in Ventura County takes 2–3 weeks of construction for a refresh, 3–5 weeks mid-range and 5–8 weeks high-end, plus 1–4 weeks of design and permits; a kitchen takes 2–4, 5–8 or 8–12 weeks, plus 1–6 weeks of permitting. HOA review, Thousand Oaks oak review and asbestos or lead testing in pre-1980 homes add the most time.
What does a remodeling contractor cost in Ventura County?
Ventura County remodels fall in our published Southern California budgeting ranges: a kitchen runs $25,000–$40,000 for a cosmetic refresh up to $70,000–$100,000+ for a full remodel, a bathroom $8,000–$18,000 up to $40,000–$80,000+, and a ground-floor room addition $300–$500 per sq ft. Scope, structure and finishes drive cost more than the city. See what remodeling costs; the estimate is free.
Which communities do you serve in and around Ventura County?
Green Design and Build serves Thousand Oaks, Newbury Park, Westlake Village, Oak Park, Agoura Hills, Simi Valley, Moorpark, Camarillo, Santa Rosa Valley, Oxnard, Port Hueneme and Ventura. We do not currently work in Ojai, Santa Paula or Fillmore. If your community is not listed, call and ask.
Recent projects near Ventura County
Our closest completed work to Ventura County, all a short drive over the county line. More completed work, with before, during and after photographs, is in the project gallery.
- Whole-Home Rebuild in Woodland Hills — a ranch house taken down to a few remaining walls: new foundations, framing, a rebuilt pool and a covered patio.
- Complete Home Remodel in Encino — taken to the studs and rebuilt, including a white kitchen with a waterfall island and a black-marble bathroom.
The full gallery is at our projects.
Ready to talk about your Ventura County project?
Send us the address and what you want to change. We will tell you which permit office and HOA are involved, whether fire-zone or oak tree rules apply, and what the schedule looks like.