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Master in Design — Tarzana home remodeling

SIMI VALLEY, CA

ADU Construction in Simi Valley

Custom backyard ADUs from a local contractor with a real office at 89 Redwood Grove Ct — not a service-area pin across the Valley.

Request a Free Estimate (855) 741-3167
Thinking About Building an ADU in Simi Valley? Start Here Simi Valley's large lots, strong rental demand, and favorable building regulations make it one of the best cities in Ventura County for ADU construction. If your home sits on a typical Simi Valley lot — and most of them are generous — you likely have the space to add a fully permitted accessory dwelling unit in your backyard.   Master in Design builds ADUs throughout Simi Valley, from Wood Ranch and Big Sky to Madera Hills, Indian Hills Ridge, and West Simi Valley. And unlike contractors who drive in from across the Valley, we have an office right here in Simi Valley.   Over 70% of Simi Valley homes are single-family detached houses, most built in the 1970s and 1980s on spacious lots when land was plentiful. That extra space is now your biggest asset — a backyard that currently holds a patch of lawn and an old shed could support a 1,200 sqft detached ADU with a kitchen, bathroom, bedroom, and living area. Homeowners are building them for rental income, an in-law suite, a private unit for adult children, a home office or studio, and the added property value a permitted ADU brings.

Remodeling Services in ADU Builder Simi Valley

Master in Design handles your ADU project from first conversation to final inspection — site evaluation, design, engineering, permit submission, full construction, and all inspections. We build all four types of ADU: detached, attached, garage conversion, and JADU, each designed to fit your lot and your goals. For a detailed breakdown of ADU types and our step-by-step process, visit our main ADU construction page.   Simi Valley handles its own permits through the City of Simi Valley Building & Safety Division — separate from LADBS and the Thousand Oaks Building Division. We know all three. The key local rules:   Size limits — Detached ADU up to 1,200 sqft; attached ADU up to 50% of the primary dwelling or 1,200 sqft (whichever is less); JADU up to 500 sqft.   Setbacks — 4-foot minimum from side and rear property lines for attached and detached ADUs.   Parking — Typically one space for attached and detached ADUs, unless your property qualifies for an exemption.   Plan check timeline — Projects requiring plan review take 20-25 working days through the Building & Safety Division.   Impact fees — ADUs 750 sqft or smaller now have zero impact fees under SB 543.   We manage all permit applications, plan submissions, and inspection scheduling, so you don't have to navigate the process yourself. Financing options are available to help manage upfront construction costs, permit fees, and finish upgrades without delaying your project.

Why ADU Builder Simi Valley homeowners hire Master in Design

We're not just a company that "also serves Simi Valley." Master in Design has a physical office at 89 Redwood Grove Ct, Simi Valley, CA 93065. When you work with us, you're working with a contractor who is part of your community.   Licensed and insured general contractor — established in 1995   Local Simi Valley office — not just a service area claim   In-house design team with custom plans for every project   Full permit management through the Simi Valley Building & Safety Division   Over 20 years of experience — led by owner Avi "Danny" Vaknin   Project guarantee on all our work   As our client Julia E. shared: "The pricing quote was fair for the project offered. The work quality was top-notch and it was completed right on schedule. I could leave home with 100% peace of mind."   Our bathroom remodeling team handles ADU interior finishes with the same attention to detail you'd expect in a full home renovation. Ready to build? Call Master in Design at (855) 741-3167 or request your free estimate online — we'll evaluate your property, explain your options, and give you a straightforward cost breakdown.

Neighborhoods we serve in ADU Builder Simi Valley

We build ADUs in every corner of Simi Valley, including:

  • Wood Ranch
  • Big Sky
  • Madera Hills
  • Indian Hills Ridge
  • West Simi Valley

ADU Builder Simi Valley Remodeling FAQ

How big of an ADU can I build in Simi Valley?

Simi Valley allows detached ADUs up to 1,200 sqft. Attached ADUs can be up to 50% of your primary dwelling's living area or 1,200 sqft, whichever is less, and a JADU (junior ADU) can be up to 500 sqft. On most Simi Valley lots — which tend to be generous — there's room for a full 1,200 sqft unit with a kitchen, bathroom, bedroom, and living area.

Do I need a permit to build an ADU in Simi Valley?

Yes. Simi Valley handles its own permits through the City of Simi Valley Building & Safety Division — separate from LADBS and the Thousand Oaks Building Division.

Projects requiring plan review take about 20-25 working days. We manage all permit applications, plan submissions, and inspection scheduling, so you don't have to navigate the process yourself.

What are the ADU setback and parking rules in Simi Valley?

Attached and detached ADUs require a 4-foot minimum setback from the side and rear property lines.

Parking is typically one space for attached and detached ADUs, unless your property qualifies for an exemption. We evaluate your specific lot and confirm exactly what applies before design begins.

What does an ADU cost to build in Simi Valley?

Cost depends on build type, size, site conditions, interior finishes, and city fees. Garage conversions are the most affordable option, while ground-up detached builds cost more but offer the most flexibility.

A compact studio costs significantly less than a full 1,200 sqft two-bedroom unit, and hillside lots in areas like Indian Hills Ridge may require additional grading. Note that ADUs 750 sqft or smaller now have zero impact fees under SB 543. We provide detailed estimates with every line item visible.

What types of ADUs do you build?

We build all four types: detached, attached, garage conversion, and JADU (junior ADU). Each is designed to fit your lot and your goals, whether that's rental income, an in-law suite, space for adult children, or a home office.

Do you offer financing for ADU construction?

Yes. Master in Design offers financing options to help Simi Valley homeowners manage upfront ADU construction costs, permit fees, and finish upgrades without delaying the project.

Are you a local Simi Valley contractor?

Yes. Master in Design has a physical office at 89 Redwood Grove Ct, Simi Valley, CA 93065 — we're part of the community, not a contractor driving in from across the Valley.

We're a licensed and insured general contractor established in 1995, with an in-house design team and over 20 years of experience led by owner Avi "Danny" Vaknin.

Why should I build an ADU on my Simi Valley property?

Simi Valley's large lots, strong rental demand, and favorable building regulations make it one of the best cities in Ventura County for an ADU.

Homeowners build them for rental income, an in-law suite, a private space for adult children, a home office or studio, and the added appraised square footage a permitted ADU brings to the property.

Which Simi Valley neighborhoods do you serve?

We build ADUs across Simi Valley, including Wood Ranch, Big Sky, Madera Hills, Indian Hills Ridge, and West Simi Valley.

Also serving the San Fernando Valley

An ADU isn't the only way we add space and value to your home. Explore our other Simi Valley services:

See all service areas →

Start your ADU Builder Simi Valley remodel

Get an honest scope and schedule from a CSLB-licensed design-build team that lives 5 to 30 minutes from your home.

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