ADU Contractor in Alum Rock, San Jose
Garage conversions and JADUs for Alum Rock's foothill homes near Alum Rock Park.
ADU Contractor San Jose·1600 Component Dr, San Jose, CA 95131
Serving Alum Rock & the foothill streets near Alum Rock Park.
Licensed & Insured
Full liability & workers' comp coverage
Free Consultation
No-obligation on-site estimates
Design & Permitting
San Jose Municipal Code 20.30.150 compliant
Full-Service Build
Design, permits & construction, start to finish
Our ADU Services in San Jose
Full-service ADU design, permitting, and construction for homeowners across San Jose and Santa Clara County.
Detached ADU Construction
New backyard ADU / granny flat construction, up to approximately 1,200 sq ft, built to San Jose ADU standards
Garage Conversion ADU
Convert an existing garage into a fully permitted living unit — ministerial approval, typical ~60-day review
Attached ADU
An addition attached to your main home, designed to match the existing structure and roofline
Junior ADU (JADU)
Up to 500 sq ft within the existing footprint of your home — an efficient, lower-cost path to added living space
ADU Design & Permitting
Architectural plans, San Jose Municipal Code 20.30.150 compliance, pre-approved ADU plans program, and full permit handling
Granny Flat / In-Law Suite
Multigenerational living units designed for comfort, privacy, and long-term flexibility
Not sure which ADU type fits your lot? Text us for a free consultation.
How It Works
From first idea to a finished, permitted ADU — our simple four-step process.
Reach Out
Text us for a free, no-obligation consultation. Tell us about your property, your goals, and your budget.
Design & Permitting
We visit your property, assess the lot, and design an ADU plan that fits your site and San Jose Municipal Code 20.30.150. We handle plan submittal and permit approval.
Construction
Our experienced crew handles the build — foundation, framing, utilities, and finishes — cleanly and on schedule, keeping you updated at every stage.
Move In
Final inspection, walkthrough, and handoff — your new ADU, JADU, or in-law suite is ready for family or tenants.
ADU Investment Guide
Every project is different — these are typical San Jose ranges to help you plan. Your exact price comes with a free, itemized estimate.
Junior ADU (JADU)
Within your home's existing footprint
From $60,000
- Free on-site consultation
- Up to 500 sq ft, built within your home
- Design & San Jose permit handling
- Efficient kitchenette & living area layout
- Typically the fastest ADU path
Garage Conversion ADU
Most popular — fast ministerial approval
$80,000 – $150,000
- Custom design plan for your garage
- San Jose Municipal Code 20.30.150 compliance
- Ministerial approval, ~60-day review
- Full utility & finish upgrade
- Project management start to finish
Detached / Attached ADU
New backyard unit or home addition
$150,000 – $400,000
- Custom architectural design
- Up to ~1,200 sq ft detached ADUs
- Attached additions matched to your home
- Full permitting & construction management
- Granny flat / in-law suite layouts available
Prices vary with size, site conditions, utility connections, and finish level. Design and permitting fees are typically $1,000–$5,000 on top of construction. Contact us for an exact quote — consultations are always free.
Recent ADU Projects in San Jose
A look at real ADU project types from our San Jose team.
Alum Rock & Every Area We Cover
ADU Contractor San Jose serves Alum Rock and every city and neighborhood across San Jose & Santa Clara County. Explore the interactive map or pick your area below.
Areas We Serve
Serving San Jose and Santa Clara County. Don't see your area listed? Text us — we most likely cover it.
Where to Find Us
ADU Contractor San Jose · 1600 Component Dr, San Jose, CA 95131 — serving Alum Rock
ADU Construction in Alum Rock, San Jose
Alum Rock, tucked against the eastern foothills near Alum Rock Park, is a mix of older single-family homes on modest lots, many dating from the mid-20th century. Given the area's typical lot sizes, a garage conversion or a Junior ADU within the existing home footprint tends to be the most cost-effective path for most Alum Rock homeowners, with detached units feasible on the flatter, larger parcels.
We treat every Alum Rock project as its own site evaluation first — confirming lot dimensions, setbacks, and existing garage condition before recommending an ADU type, so you're not paying for design work on an option that won't clear approval. Text us for a free, no-obligation consultation.
Frequently Asked Questions
Everything you need to know about building an ADU in San Jose.
Costs vary widely with size and scope. A garage conversion ADU typically runs $80,000–$150,000, an attached ADU addition $150,000–$300,000, and a new detached ADU $250,000–$400,000. Design and permitting fees are typically $1,000–$5,000 on top of construction. We give you a clear, itemized estimate after a free on-site consultation — text us to get started.
Get Your Free Consultation
Ready to add an ADU, garage conversion, or in-law suite? Text us for a free, no-obligation consultation and estimate anywhere in San Jose & Santa Clara County.
Licensed
& Insured
Free
Consultations