One team, one contact
Design, engineering, permits, and construction handled in-house — so nothing gets lost between vendors and your timeline stays tight.
Southern California ADU Design-Build
Turn your backyard into income, space, and lasting value.
Custom-designed, permit-to-completion ADUs built by one integrated team — architecture, engineering, and construction under a single roof. No juggling contractors. No guesswork.
- Licensed & Insured · CSLB #982238
- 100+ ADUs Built
- 5-Star Rated
- Serving the Inland Empire
$0
hidden fees — transparent, fixed pricing on every build
100+
ADUs Built
5.0★
Client Rating
1
Integrated Team
100%
Permits Managed
Why Us
Most contractors build. We design, engineer, and build — as one.
The typical ADU project means hiring an architect, an engineer, a permit expediter, and a builder separately — then hoping they talk to each other. We put all of it under one roof, one contract, one point of contact.
In-house design & engineering
Architectural design and structural engineering built to pass the first time — no outsourcing, no finger-pointing, no costly redraws.
Local permit expertise
We know Inland Empire and LA-area city departments — zoning, setbacks, and approvals managed start to finish, so you never touch a permit desk.
Transparent fixed pricing
A clear, itemized number before we break ground — and honest advice. If your property won't pencil out, we tell you before you spend a dollar.
The Difference
We’re not just builders.
We’re not just builders.
We’re ADU strategists.
Every property is different. Before we draw a single line, we look at what your lot, your goals, and your budget can actually support — rental income, multigenerational space, or long-term value — then engineer the smartest path to it.
- 1
Strategy before shovels
We model the ROI and design around your goal, not a template.
- 2
Built to appraise and rent
Finishes and layouts chosen to maximize value and rentability.
- 3
No surprises
Fixed scope, fixed price, and a single point of accountability.
Featured Projects
Craftsmanship you can walk through.
A selection of custom ADUs across Southern California — from backyard studios to full multigenerational homes.
Kitchen Remodel
Chef’s Kitchen Transformation
Kitchen Remodel
Waterfall Island Kitchen
Outdoor Living
Resort-Style Backyard
Outdoor Living
Entertainer’s Patio
Addition & Exterior
Covered Patio Addition
Outdoor Living
Fire Pit & Deck Lounge
What We Build
Every ADU path, engineered end to end.
Whichever route fits your lot and your goals, one team carries it from first sketch to final inspection.
Detached ADUs
A standalone home in your backyard — the highest value and rental potential.
- Max rental income & appraisal value
- Full kitchen, bath & private entry
Garage Conversions
Turn an underused garage into livable, income-ready square footage — fast.
- Lower cost, shorter timeline
- Uses existing footprint & utilities
Junior ADUs (JADU)
A compact unit within your home’s footprint — the fastest path to approval.
- Streamlined permitting
- Ideal for family or first rental
Multi-ADU & Investment
Stack multiple units where zoning allows and build a real cash-flowing asset.
- Multiple income streams
- Feasibility & ROI modeling included
Design & Engineering
Architectural design and structural engineering, in-house and coordinated.
- Plans built to pass on first submittal
- Design tuned to value & rentability
Permits & Construction
City approvals and full construction management, handled entirely for you.
- Zoning, permits & inspections managed
- One accountable point of contact
Our Process
From first call to keys in hand.
A clear, guided path — you always know exactly where your project stands and what happens next.
01
Discovery
We learn your goals, your lot, and your budget on a free consultation.
Day 102
Feasibility
Zoning, setbacks, and utilities checked — plus a real ROI picture.
Week 1–203
Design
Architectural plans tailored to value, rentability, and how you’ll live.
Week 2–604
Engineering
Structural engineering completed in-house and coordinated with design.
Week 4–805
Permits
We submit, manage corrections, and secure city approval for you.
1–4 months06
Construction
Your dedicated team builds it — clean, on-schedule, and communicative.
4–8 months07
Final Walkthrough
Final inspection, walkthrough, and handoff — ready to move in or rent.
Completion08
Support
Warranty and guidance after handoff — we’re here beyond the build.
Ongoing
Before & After
The same backyard. A very different asset.
Before
After
Client Stories
Homeowners who bet on their backyard.
5.0 Google Rated · 4 reviews
“I highly recommend JBC Design & Build Co. Joe and his team have renovated many of my properties and have done an excellent job. Their pricing is very reasonable and they are efficient and fast.”
G
Ghislaine “Lisa” Villeneuve
Verified Google review
“I recently had my kitchen remodeled and I wanted to acknowledge JBC Design & Build for the excellent work they did. Joe was very professional and quick in providing an estimate.”
R
Rosie Martinez
Verified Google review
“JBC Design and Build have been doing my architectural designs for years. Very professional and always on time. They also build all of my ADUs in the area. Quality workmanship.”
J
Jose Cardenas
Verified Google review
“Joe and his crew built a multimillion-dollar house that I designed and everything turned out great. Our client was very happy with his work.”
C
Cesar Beltran
Verified Google review
Areas Served
Building across the Inland Empire & Greater LA.
Deep, local knowledge of city building departments across Southern California — so your permits move and your project doesn’t stall.
Questions, Answered
Everything you’re wondering about ADUs.
ADU costs vary by size, finishes, and site conditions. Most detached ADUs in Southern California range from the low $100Ks to $300K+. After your free feasibility review we provide clear, transparent pricing — no hidden fees, no surprise change orders.
Most single-family and multi-family lots in California qualify under state ADU law. We check zoning, setbacks, and utilities during your free feasibility review — and if your property doesn’t qualify, we tell you upfront before you spend a dollar.
Design and permitting typically take 3 to 6 months, and construction 4 to 8 months depending on size and city. Because design, engineering, and construction all happen in-house, we keep the timeline as tight as possible.
Yes. Depending on size and location, ADUs in our service area commonly rent for $1,200 to $3,500 per month and can add $100K–$400K+ in property value.
Homeowners commonly use home equity loans, HELOCs, construction loans, or cash-out refinancing. We connect you with trusted lenders who specialize in ADU projects and can use projected rental income to help you qualify.
Completely. Permitting and city compliance are fully managed for you — submittals, corrections, and inspections. No permit confusion, no city runaround.
Free ADU Feasibility Review
Find out what your property can build — in about 60 seconds.
Answer a few quick questions and our team will review your lot, check eligibility, and send back a no-pressure feasibility snapshot with real numbers.
- 100% free — no obligation, no pushy sales
- Honest answer, even if it’s “not a fit”
- Real rental & value estimates for your area
Prefer to talk now?
(951) 515-4926