Best ADU Builders in Sunnyvale CA

If you’re planning to build an ADU in Sunnyvale, We provide complete design-build services tailored to your property and goals.  

Licensed & Insured ADU Builders in Sunnyvale, CA

As licensed and insured ADU builders in Sunnyvale, DevArt8 delivers code-compliant construction backed by professional project management and structural expertise. We handle permits, engineering, and inspections to ensure your accessory dwelling unit is built safely, legally, and to the highest quality standards.

Sunnyvale ADU Regulation Expertise

Deep understanding of local zoning codes, setback requirements, and Sunnyvale-specific ADU regulations

End-to-End Design & Construction

From initial concept through final inspections, we manage your entire ADU project

In-House Project Management

Dedicated coordination of all trades, timelines, and city approvals

Transparent Pricing & Timelines

Clear budgets with no hidden costs and realistic construction schedules

Quality Materials & Craftsmanship

High-quality construction that maximizes your ADU's value and longevity

Our ADU Construction Services in Sunnyvale

Detached ADUs

Stand alone private units

Attached ADUs

Connected in law units

Garage Conversion ADUs

Garage to living space

Junior ADUs (JADUs)

Compact in home units

Custom ADU Design & Planning

Custom design and layouts

Permitting & City Approvals

Full permit management

Sunnyvale ADU Design & Construction Projects

before

Existing Property / Garage / Yard Space

After

Completed ADU in San Jose

Before

Existing Property / Garage / Yard Space

After

Completed ADU in San Jose

What Sunnyvale Homeowners Say

ADU Builders Sunnyvale – Frequently Asked Questions

Are ADUs allowed on residential properties in Sunnyvale, CA?

Yes. Most single-family properties in Sunnyvale qualify for at least one ADU under California state law. However, lot size, zoning designation, setbacks, and utility access must be reviewed before approval.

The cost of building an ADU in Sunnyvale depends on size, design type (detached, attached, or garage conversion), site preparation, and interior finishes. Detached ADUs typically require a higher investment than garage conversions due to new foundations and infrastructure.

The full process—including design, permitting, and construction—can take 8 to 14 months. Construction typically lasts 4 to 6 months once permits are approved, depending on project complexity.

Not always. Many ADUs share utilities with the primary residence, though electrical panel upgrades or sewer capacity evaluations may be required to meet building codes.

California law allows detached ADUs up to 800 square feet with streamlined approval in many situations. Larger sizes may be possible depending on lot size and zoning regulations.