Build a High-Value ADU Without the Headaches
Custom Design + Full Construction Management — From Permits to Final Inspection.
Increase property value, create rental income, or build space for family — we handle everything.
Takes 60 seconds. No obligation.
Licensed & Insured
100+ ADUs Built
5-Star Rated
Why ADUs Are the Smartest Move for California Homeowners
Transform your property into a valuable asset
Generate Passive Rental Income
Create a steady monthly income stream
from your property while you sleep.
Increase Property Value Significantly
ADUs can add $150K-$400K+ to your
property's market value.
Multi-Generational Living Space
Keep family close while maintaining
privacy and independence.
Add 1-3 Additional Units
Depending on your lot size and zoning, maximize your property potential.
Offset Mortgage Costs
Rental income can cover a significant portion of your monthly payments.
Create Home Office or Studio
Perfect workspace separate from your main residence.
We Handle Everything — Start to Finish
Our proven 3-step process takes you from concept to completion
Property Assessment
We evaluate zoning, lot size, utilities, and feasibility to determine what's possible on your property.
Custom Design + Permits
Architectural plans, engineering, and city approvals — all managed by our expert team.
Full Construction + Delivery
Ground-up build, inspections, and final walk-through with quality guaranteed.
No juggling contractors. No permit confusion. No guesswork.
Why Work With JBC Instead of a General Contractor?
We're not just builders. We're ADU strategists.
In-House Design + Build Team
Seamless coordination between architects and builders under one roof.
Experience Navigating Local City Approvals
We know the ins and outs of California permitting and regulations.
Transparent Budgeting Process
No hidden fees. Clear line-item breakdowns from day one.
Timeline Management
We keep your project on schedule with proactive communication.
No Handoffs Between Architect and Builder
One team, one vision, one point of contact throughout.
Traditional Approach
Multiple contractors to coordinate
Communication breakdowns
Delayed timelines
Design vs. build conflicts
Surprise costs
The JBC Way
Single point of contact
Seamless communication
On-time delivery
Unified design + build
Transparent pricing
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What Could an ADU Do for Your Property?
Real numbers from real California ADU projects
Studio ADU
400-500 sq ft
Rental Potential:
$1,200 - $1,800/month
Property Value Increase:
$100K - $200K+
Best For:
Single Occupants, Home Office
1-Bedroom ADU
500-700 sq ft
Rental Potential:
$1,800 - $2,500/month
Property Value Increase:
$150K - $300K+
Best For:
Couples, families, long-term rental
Up to 4-Bedroom ADU
700-1,200 sq ft
Rental Potential:
$2,500 - $3,500/month
Property Value Increase:
$200K - $400K+
Best For:
Families, maximum rental income
*Rental and appreciation estimates vary by location, market conditions, and property characteristics. Figures shown represent potential ranges in California markets.
Concerned About Permits, Cost, or City Approval
We remove the uncertainty and guide you through every challenge
Zoning Analysis
We determine exactly what's
allowed on your property
and maximize your options.
Budget Planning
Detailed cost breakdowns
and realistic projections
before you commit.
Financing Referrals
Connected with trusted lenders
who specialize in
ADU projects.
Utility Connections
We coordinate all water,
sewer, gas,
and electrical requirements.
City Compliance
Expert navigation
of local building
codes and permit processes.
Risk Management
Comprehensive insurance
and warranty protection
for your investment.
Honest Approach: If your property doesn't qualify for an ADU — we'll tell you upfront. No wasted time or false hopes.
What others are saying
Real results from real California homeowners
"JBC made the entire process seamless. From design to completion, they handled everything. Now I'm generating $2,200/month in rental income that more than covers my mortgage!"
Sarah M.
San Jose, CA
"I was worried about permits and city approval, but JBC's team handled everything. They knew exactly what the city needed. The project was completed on time and my parents now have their own beautiful space."
David & Leah
San Jose, CA
"The transparency and communication throughout the build was outstanding. No surprises, no hidden costs. My property value increased by over $200K. Best investment I've ever made."
Michael R.
San Jose, CA
Licensed & Insured
100+ ADUs Built
5-Star Rated
Frequently Asked Questions
Get answers to common questions about ADU projects
How long does it take to build an ADU?
Typically 6-12 months from initial consultation to completion, depending on the city's permit approval process and project scope. Design and permitting usually take 2-4 months, and construction takes 4-8 months. We provide detailed timelines during your feasibility review.
How much does an ADU cost?
Costs vary based on size, finishes, and site conditions. Generally, expect $200-$400 per square foot for a complete turnkey ADU. A 600 sq ft unit typically ranges from $120K-$240K. We provide detailed estimates after your property assessment so you know exactly what to expect.
Do you help with financing?
Yes! We can connect you with lenders who specialize in ADU financing, including home equity loans, construction loans, and cash-out refinancing options. Many of our clients use rental income projections to qualify for favorable loan terms.
Can I build more than one ADU on my property?
Depending on your lot size and local zoning laws — often yes! California's recent ADU legislation allows for multiple units in many cases: a detached ADU, a Junior ADU, and sometimes garage conversions. We analyze your specific property to maximize potential.
What's the difference between a detached ADU and a garage conversion?
A detached ADU is a brand-new structure built separately from your main house, while a garage conversion transforms your existing garage into living space. Garage conversions are often faster and less expensive, but detached ADUs typically offer more design flexibility and rental value.
Will an ADU affect my property taxes?
Yes, adding an ADU will increase your property's assessed value, which means higher property taxes. However, the rental income or increased property value typically far exceeds the tax increase. We can help you run the numbers to see your net return on investment.
Do I need to live on the property to build an ADU?
As of January 2021, California law eliminated the owner-occupancy requirement for ADUs (until 2025). This means you can build and rent out an ADU even if you don't live in the main house. However, local jurisdictions may have specific rules, which we help you navigate.
What if my property doesn't qualify for an ADU?
We'll tell you honestly during the feasibility review. Factors like lot size, setbacks, utility access, and local zoning can affect eligibility. If an ADU isn't possible, we'll explain why and discuss any alternative options that might work for your property.
Your Property Might Already Qualify.
Don't Guess. Get a Professional Review.
Limited availability — We take on a select number of projects each quarter to ensure quality.
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