General B Lic # 1148425
Architecture, Permits, Construction — All Under One Roof. Affordable, Seamless Delivery!
Design And Build Firm · San Jose, CA · South Bay Area
ADU Contractor in San Jose, CA - Design, Permits & Build
Urban Nest is San Jose’s trusted ADU contractor for Accessory Dwelling Unit construction. We handle everything from architectural design and permit filing to full construction in the Bay Area, CA. You don’t have to manage a dozen different contractors.
Guaranteed On-Time Completion
Full-Coverage Installation Warranty
Workmanship + materials
15+ Years Specialized Experience
In-house design-build team
CA Licensed Contractor
CSLB #1148425
Why choose an ADU contractor?
Why San Jose Homeowners Are Adding ADUs
San Jose’s housing shortage and California’s ADU-friendly laws have made accessory dwelling unit construction one of the highest-ROI moves a local homeowner can make, either in monthly rental income or making their property more valuable for buyers. Whether you’re building a detached backyard cottage, converting a garage, or adding a junior ADU, Urban Nest manages the entire design, permit, and construction process under one roof.
Strong Rental Income
San Jose 1-bedroom rents average $2,200–$2,800/month. A well-built ADU often pays for itself within 5–8 years. Working with an experienced ADU design-build firm ensures your unit is built to rental-grade standards from day one.
Property Value Boost
Studies consistently show that adding an ADU increases property value by 20–30% in Bay Area markets. Unlike a standard renovation, an accessory dwelling unit adds a fully independent living space that appraisers recognize as income-producing square footage.
Multigenerational Living
Keep family close with a private, independent space, without sacrificing anyone’s privacy. A purpose-designed ADU home, with its own entrance, kitchen, and bathroom, gives aging parents or adult children the independence they need while keeping your household connected, and eliminates the ongoing cost of assisted living or separate rental housing.
City Support
San Jose has streamlined ADU permitting, ministerial approval (no public hearing) for projects meeting objective standards. A local design-build firm with deep knowledge of San Jose’s Development Services Department can navigate plan check requirements, coordinate with Public Works and Fire, and keep your project on the fastest possible approval track.
ADU Types We Build
Types of ADUs We Build in San Jose
Every property is different. Urban Nest evaluates your lot, zoning, and goals to recommend the ADU type that gives you the most space, value, and return for your investment. As a San Jose–based ADU contractor, we conduct a full feasibility assessment before recommending a construction path that fits your property, budget, and timeline.
Detached ADU (Backyard Cottage)
A brand-new, standalone structure built in your rear yard. Detached ADUs offer the most privacy and independence, ideal for rental income or family members who want their own front door. In San Jose, detached ADUs on single-family lots can be up to 1,000–1,200 sq ft depending on lot size.
Attached ADU (Home Addition)
An ADU that shares a wall or roof structure with your primary home. Typically more cost-effective than detached builds because it leverages existing structure, but still delivers a fully independent living space with a separate entrance.
Garage Conversion ADU
Transform an underutilized garage into a livable, code-compliant ADU. Often the most affordable ADU type and can move through permitting faster since the structural shell already exists. We specialize in creative, functional garage-to-ADU transformations.
Junior ADU (JADU)
A smaller secondary unit, up to 500 sq ft, created within the existing footprint of your primary home. JADUs include a kitchenette and share some systems with the main house. A cost-effective entry point if you have underused interior space.
Second-Story ADU
For properties with limited rear yard space, a second-story ADU above a garage or as an addition can unlock significant square footage without expanding your ground-level footprint. This ADU type maximizes land value while preserving outdoor space, making it a smart solution for homeowners without sacrificing their backyard.
1
Free Property Consultation & Feasibility
We visit your property (or conduct a virtual assessment), review your zoning, setbacks, lot coverage, utilities, and any special overlays like hillside or historic districts. We tell you exactly what you can build before you spend a dollar.
2
Custom Architectural Design
Our licensed architects design your ADU to maximize space, budget, and aesthetic. We produce full construction drawings, site plan, floor plans, elevations, structural, mechanical, electrical, and plumbing, everything the City needs to issue your permit.
3
Permit Filing & Expediting
We manage all permit submissions to the City of San Jose’s Development Services Department, coordinate with Public Works and Fire as needed, and track your application through to approval. Most ADUs that meet objective standards qualify for ministerial review.
4
Full Construction
Our licensed construction team builds your ADU to the approved plans, coordinating all subcontractors and scheduling City inspections at each required phase. We keep you updated throughout so there are no surprises.
5
Final Inspection & Handover
We walk your completed ADU through final City inspection and occupancy sign-off, then hand you the keys and all project documentation.
Our Process
How Urban Nest Manages Your ADU from Start to Finish
One of the biggest challenges in ADU construction is managing multiple specialists, architects, engineers, permit expediters, and general contractors, who often don’t communicate well with each other. Urban Nest eliminates that friction. We are a single-contract design-build team: one point of contact, one accountability structure, and no gaps between design intent and construction reality.
Quick Reference
San Jose ADU Requirements
Understanding San Jose’s ADU rules before you plan is essential, lot size, zoning, and ADU type all affect what you can build. Here’s a summary of the key standards an ADU contractor must follow for single-family properties.
| Requirement | Single-Family Properties |
|---|---|
|
Allowed zones |
R-1, R-2, R-M, PD + designated General Plan areas |
|
Units allowed |
1 ADU + 1 JADU per lot |
|
Detached ADU max size |
1,000 sq ft (lots <9,000 sq ft) / 1,200 sq ft (lots ≥9,000 sq ft) |
|
Attached ADU max size |
Up to 50% of primary home, max 1,200 sq ft |
|
JADU max size |
500 sq ft |
|
Min. front setback (detached) |
45 feet from front property line |
|
Rear/Side setback (ground floor) |
3 feet minimum |
|
Max height (1-story detached) |
18 feet |
|
Allowed zones |
R-1, R-2, R-M, PD + designated General Plan areas |
|
Max height (2-story detached) |
24 feet |
|
Parking requirement |
Limited by state law; many ADUs are exempt |
|
Permitting path |
Ministerial (no public hearing) if objective standards are met |
Note: Rules for multifamily properties differ. Contact us for a property-specific assessment. View official San Jose ADU regulations →
Investment
How Much Does an ADU Cost in San Jose?
San Jose sits in the heart of the Bay Area, and construction costs reflect that when hiring an ADU contractor. Here are realistic ranges to anchor your planning, but actual costs depend heavily on your specific lot, ADU type, finishes, and utility conditions.
| Typical Cost Range | Single-Family Properties |
|---|---|
|
Garage conversion |
$80,000 – $180,000 |
|
JADU (interior conversion) |
$60,000 – $130,000 |
|
Attached ADU |
$180,000 – $350,000 |
|
Detached ADU (new build) |
$250,000 – $500,000+ |
What drives cost up
- Sloped or constrained lots requiring retaining walls or grading
- New sewer lateral or water service upgrades
- High-end finishes or custom design features
- Second-story additions
What keeps cost down
- Garage or interior conversions (existing structure)
- Standard finishes and efficient layouts
- Properties with existing utility access
- Working with a design-build firm (reduces redesign costs and delays)
Why Urban Nest
Trusted by San Jose & Bay Area Homeowners
“Urban Nest supported us every step of the way with great suggestions, an easy-to-work-with network of suppliers, and a friendly staff that made the experience as easy as possible. We will most definitely choose Urban Nest again for our next project.”
– Verified Urban Nest Client
FAQ
Hiring an ADU Contractor in San Jose & The Bay Area — Your Questions, Answered
What is an accessory dwelling unit (ADU)?
An accessory dwelling unit (ADU) is a secondary housing unit built on the same lot as an existing primary residence. It includes all the features needed for independent living — a kitchen, bathroom, sleeping area, and separate entrance. In San Jose, ADUs are also called granny flats, backyard cottages, in-law suites, or carriage houses.
How long does it take to build an ADU in San Jose?
Timeline varies by project type. A garage conversion may take 4–8 months from design to occupancy. A new detached ADU typically runs 10–18 months, including design, permit review, and construction. San Jose’s ministerial review process helps speed up approval for projects that meet objective standards. Urban Nest will give you a realistic schedule during your consultation.
Do I need a permit to build an ADU in San Jose?
Yes. All ADUs require building permits from the City of San Jose. You’ll need Planning, Building, and possibly Public Works and Fire department review. Urban Nest handles the entire permit process as part of our service.
Can I rent out my ADU in San Jose?
Yes, ADUs can be rented as long-term rental units in San Jose. If you’re considering short-term rentals (Airbnb, VRBO), the City has additional registration and licensing requirements you’ll need to meet.
Will building an ADU increase my property taxes?
Yes, the Santa Clara County Assessor will reassess the value of your property based on the improvement. Only the value of the ADU addition is reassessed, not your entire home, so the impact is typically proportional to construction cost. We recommend consulting a tax advisor for specifics.
Can I build an ADU if I have an HOA?
California law limits an HOA’s ability to outright prohibit ADUs, but HOAs can impose design standards related to color, materials, and appearance. We review HOA CC&Rs early in our process to avoid redesigns.
Do I have to live on the property to build an ADU in San Jose?
For detached ADUs and attached ADUs, there is no owner-occupancy requirement in San Jose under current California law. JADUs (Junior ADUs), however, typically require the owner to occupy either the main home or the JADU.
What's the difference between an ADU and a JADU?
A full ADU is an independent dwelling with its own kitchen and bathroom, and can be detached or attached. A Junior ADU (JADU) is smaller (max 500 sq ft), must be within the existing home footprint, and can include a kitchenette that shares plumbing with the main house. JADUs are generally faster and cheaper to build.
How does Urban Nest price ADU projects?
We provide a detailed, itemized proposal after your free consultation and site visit. We don’t do vague square-footage estimates, you’ll receive a clear breakdown of design, permitting, and construction costs before committing to anything.
Call us at 408-807-8143 or fill out our online form to schedule a free, no-obligation property consultation. We’ll assess your lot, walk through your options, and give you an honest picture of what’s possible.
Project Gallery
Our ADU Projects in San Jose
Detached ADU (Backyard Cottage)
Willow Glen · 950 sq ft
Garage Conversion ADU
Cambrian Park · 420 sq ft
Attached ADU Interior
Almaden Valley · 720 sq ft
Modern Detached ADU
Evergreen · 1,100 sq ft
Why Urban Nest
Why San Jose Homeowners Choose Urban Nest
Licensed & Fully Insured
CA General B License #1148425. We carry full general liability and workers’ compensation insurance on every project. Never build an ADU with an unlicensed contractor, the liability risk is enormous.
Architecture + Permits + Construction — One Contract
Most homeowners juggling separate architects, permit runners, and contractors end up with communication breakdowns, cost overruns, and delays. Urban Nest delivers the entire project under one roof and one contract, no finger-pointing, no gaps.
Deep Local Knowledge
We’re based in San Jose. Our team knows the City’s permit department, the local zoning nuances, and the contractor landscape, meaning faster permit turnarounds and no costly surprises from unfamiliar site conditions.
Transparent Pricing
We provide detailed, itemized proposals, no vague estimates that explode mid-project. You’ll know what you’re building and what it costs before we break ground.
Full-Service Architectural Capability
Unlike contractors who outsource architecture, our in-house design team creates plans optimized for both your lifestyle and constructability with fewer change orders, smoother builds.
Proven Bay Area Track Record
15+ years of experience and hundreds of completed projects across San Jose and the Bay Area, with an established reputation for quality and reliability.
Service Areas
ADU Contractor Across San Jose & the Bay Area
Urban Nest serves homeowners throughout San Jose and the San Francisco Bay Area, including:
- San Jose (Willow Glen, Almaden, Berryessa, Cambrian, Evergreen, Rose Garden, Silver Creek, Blossom Hill)
- Almaden Valley
- Santa Clara
- Cambrian Park
- Los Gatos
- Saratoga
- Mountain View
- Sunnyvale
Credentials
Licensed, Certified & Professionally Recognized
When you hire an ADU contractor in San Jose, like Urban Nest, you’re working with a fully credentialed ADU contractor, not a handyman, jack-of-all-trades, or unlicensed crew. We specialize exclusively in ADU construction, from custom cabinetry and countertop installation to full electrical and plumbing coordination.
CA Licensed General Contractor #1148425
Fully Bonded — Surety Bond on file
Workers’ Compensation Insurance
NALP — Member
Google Local Services Verified
CONTACT
- 20777 Mountain Dr San Jose, CA 95120
- 4088078143
- info@urbannestinc.com
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