ADU Builder San Jose
Custom, High-Quality Accessory Dwelling Units
Are you looking to build an Accessory Dwelling Unit (ADU) in San Jose, CA?
Keep Your Family Close with a Custom ADU
Whether you want to create a comfortable space for aging parents, independent living for adult children, or a guest house for extended family, ADU Builders Group is your trusted ADU builder in San Jose, California.
With over 20 years of experience, we specialize in designing and constructing high-quality, custom-built ADUs that strengthen family bonds, enhance multigenerational living, and improve your lifestyle while ensuring compliance with local building regulations.
Build with Peace of Mind
We are the only ADU company in San Jose that offers a three (3) years project warranty on our services with complementary annual project inspection. All of this on top of the ten (10) years warranty on structural components.
✔ 3 Years Project Warranty
✔ Complimentary Annual Inspection
✔ 10 Years Structural Warranty
Why Choose Us?
1. Peace of Mind with Industry-Leading Warranties
✅ 3 Years Project Warranty – We stand by our craftsmanship, ensuring any issues within the first three years are addressed promptly and professionally.
✅ Free Annual Inspection – Our commitment to quality extends beyond project completion, we provide a free annual inspection, for the first three years after project completion, to ensure your ADU remains in excellent condition.
✅ 10 Years Structural Warranty – Our ADUs are built to last, and we back them with a decade-long structural warranty, giving you confidence in the longevity of your investment.
2. Expert Guidance & Hassle-Free Process
✅ Permitting & Compliance Experts – Navigating San Jose's ADU regulations can be complex, but our experienced team ensures a smooth approval process, handling all paperwork and city requirements to prevent costly delays.
✅ 20+ Years of Construction Expertise – With decades of expertise in the construction industry and a dedicated focus on ADUs for over five years, we bring the knowledge, efficiency, and craftsmanship necessary to deliver high-quality results every time.
✅ Fast & Efficient Construction – Our streamlined process and skilled project management ensure your ADU is completed on time without unnecessary disruptions to your daily life.
3. Superior Craftsmanship & Custom Designs
✅ Aging-in-Place & Accessibility Features – Our ADUs are designed with the future in mind, incorporating accessibility features such as wider doorways, step-free entrances, and senior-friendly layouts for long-term convenience.
✅ Tailored Solutions for Every Home – Every family’s needs are unique, which is why we create custom ADU designs that maximize space efficiency, match your home’s aesthetics, and fit your lifestyle.
✅ High-Quality Materials & Precision Engineering – We use only top-tier materials sourced from our trusted, high-quality suppliers, ensuring that your ADU is durable, safe, and built to last for generations.
4. A Lifestyle Solution for Your Family's Needs
✅ Keep Loved Ones Close – Give elderly parents or adult children a private yet nearby living space, ensuring family members stay connected while maintaining their independence.
✅ Multigenerational Living Made Easy – Whether it's providing a comfortable home for aging parents or giving young adults a head start, our ADUs foster a supportive and practical living arrangement.
✅ Enhance Your Home’s Functionality – More than just extra space, an ADU can serve as a dedicated home office, personal gym, creative studio, or even a guest house for visiting relatives and friends.
About Us
Partners and Affiliations
ADU Builders Group Inc.
ADU Builders Group is a local, family-owned company dedicated to providing innovative solutions to California’s housing crisis, with passion for helping multigenerational families. Having high regards to family-oriented values, our work reflects a deep commitment to creating practical, high-quality custom ADUs that bring loved ones closer while respecting privacy and independence. With heart, craftsmanship, and a focus on community, we build homes that inspire and unite.
✔ Proudly Local
✔ Family-Owned
✔ Licensed and Insured
A Partner & Sister-Company of
Imagine Unique Remodels
Our Services and Expertise
.jpeg)
What's The Best Type of ADU for You?
Our Process
Consult with our ADU Experts
1
To start, discuss your needs, goals, and vision for your ADU with our experts. Start by having a phone consultation with us at (408) 413-3373. We'll set your schedule for the in-person meeting during the call. You'll receive expert recommendations and estimate for your ADU during the consultation phase at no cost.
2
Design with our Architect
Need to customize your ADU based on your needs and requirements? Design your own ADU and turn your ideas into an architectural plan with our Architect.
4
Construct & Pass Inspections
Our Project Managers will be in constant communication with you during construction and will ensure that your projects pass all inspections.
3
Obtain Permits Effortlessly
Our Liaison Officer will take care of the permits for you and work with the city to ensure that all paperworks are in place quickly and efficiently.
5
Enjoy and Maintain your ADU
Live the lifestyle you want and be worry-free. We'll continue to provide support and care to your project with our warranties and annual project inspection.
Local ADU Regulations in San Jose
Below is an overview of San Jose's ADU regulations. For details specific to your property, reach out to us to speak with an ADU specialist.
Where ADUs Are Permitted
ADUs are generally allowed on properties designated for residential use, though certain exceptions may apply. To qualify, the property must already have—or plan to have—a single-family home or a multi-family residential structure, such as a duplex or apartment building. Get in touch with our team to find out if your property qualifies.
Lot Size Requirements
There are no minimum lot size restrictions—any property can accommodate an ADU regardless of its dimensions.
Number of ADUs Allowed
Single-family properties can typically add one or two ADUs. Multi-family properties may be eligible for multiple ADUs, depending on the existing number of units and the ADU type. Contact us today to discuss how many ADUs your property can support.
Parking Rules
Conversion and junior ADUs typically do not require additional parking. However, attached and detached ADUs generally require one parking space unless an exemption applies. To verify whether parking is necessary for your project, contact us for expert advice on ADU parking requirements.
Featured Project
ADU Builder San Jose FAQs
How long does it take to build a backyard cottage or in-law unit in San Jose?
The full process typically takes 8 to 12 months, depending on project scope and permitting speed. This includes 1–2 months for planning and design, 2–4 months for permit approval, and 4–6 months for construction. Using a pre-approved plan or simplified layout can shorten the timeline.
What’s the average cost to build a secondary living space in San Jose?
Construction costs usually range from $450 to $475 per square foot. A 750 sq. ft. compact home might start at $340,000, while larger or custom builds can exceed $500,000. Additional expenses include site prep, utility upgrades, permit fees, and landscaping.
Can the new unit share utilities with the main house?
Yes. Most secondary dwellings in San Jose are connected to the primary home’s water, sewer, and electrical lines. However, separate utility meters may be required—or preferred—if the space will be used as a rental. Some older homes may also need electrical panel upgrades.
Are there incentives for green building or energy efficiency?
Absolutely. San Jose homeowners may qualify for BayREN rebates, solar installation programs, and EV charging incentives. All new homes must meet California’s Title 24 energy codes, and secondary dwellings under 750 sq. ft. are exempt from city impact fees.
Why are residents adding compact units or guest houses?
These small homes offer versatile space for extended family, renters, or live-in caregivers. They can also be used as home offices, studios, or short-term rental options, making them a valuable asset in a competitive housing market.
Is there high demand for these types of units in San Jose?
Yes. Due to limited housing inventory, high living costs, and zoning flexibility, many homeowners are turning to garage conversions, detached garden flats, or studio suites to expand their property’s potential.
What are the most popular styles for these dwellings?
Designs vary but often include open-concept layouts, vaulted ceilings, smart home features, and modern or Craftsman architecture. Many units are designed to blend seamlessly with the existing home while offering privacy and efficiency.
Where can I get help with planning and permitting?
The City of San Jose Planning Department provides resources such as zoning maps, permit checklists, and pre-approved floor plans. Homeowners can also request a pre-application consultation to evaluate their site’s feasibility.
Will adding a small second home change the neighborhood?
Not in a disruptive way. San Jose has established guidelines to ensure new units meet height, design, and setback standards so they remain in harmony with existing homes. These additions allow for gentle density while preserving community aesthetics.
Do I need to add parking for the new unit?
In most cases, no additional parking is required if the unit is within ½ mile of public transit—a common scenario in San Jose. Otherwise, one off-street space may be required unless you’re converting part of an existing structure like a garage.
Service Areas
Want to build your own ADU but don't know how to start?
Consult with Us Now
By requesting a callback using our form.
Get expert advice and professional guidance from our ADU Experts!