Portola Valley ADU Contractor - Custom Designed for Your Needs

Adding a custom-designed ADU on your property has never been easier when you hire Sigura Construction. 24 years experience, BBB A+ accredited and Diamond Certified.

Sigura Construction: ADU & Garage Conversion Experts.

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As a Portola Valley ADU contractor, Sigura Construction makes the entire process simple and stress-free. We white-glove every step of the ADU or garage conversion process, ensuring every Portola Valley code requirement is met while working with you from start to finish. From the initial design to the finished product, your custom ADU or garage conversion will be fully permitted and tailored to your needs.

Bay Area homeowners are looking for better ways to keep family close or turn extra space into a lucrative source of Airbnb rental income. Now more than ever, especially in Portola Valley, it’s becoming easier to build ADUs and garage conversions. Now's the time to take advantage of the opportunity!

With 24 years in the construction industry, an A+ BBB rating, and Diamond Certified status for 18 years, we’re a trusted ADU construction company proudly serving Portola Valley and the greater San Mateo and Santa Clara County areas.

Portola Valley ADU Regulations: What You Need to Know in 2026

Inside a cozy ADU in Walnut Creek

ADUs remain an attractive option for Portola Valley homeowners thanks to California state housing laws, even with the town’s focus on preserving its rural character, hillside settings, and environmental standards. Whether you want a detached backyard cottage, garage conversion, attached in-law suite, or Junior ADU (JADU), thoughtful planning makes these projects achievable.

Key Highlights:

  • No statewide minimum lot size for ADUs
  • JADUs up to 500 sq ft; internal conversions and attached ADUs often up to 1,200 sq ft (larger options available with review)
  • Detached ADUs typically allowed up to 1,200–1,500 sq ft depending on parcel size
  • 4 ft side and rear setbacks commonly permitted for qualifying ADUs under state law
  • Height limits usually 16–18 ft for detached units (higher may require review)
  • Ministerial (by-right) approval for most qualifying projects — no public hearings needed
  • Garage conversions and interior ADUs are often the simplest and most cost-effective path
  • One parking space typically required for new detached units (can often be tandem or uncovered)
  • Must meet fire safety (Woodside Fire District), geologic, septic, and Title 24 energy standards

We handle the entire process from initial zoning review and site measurements to custom design, full permit plans, engineering coordination, and direct communication with Portola Valley Planning & Building staff. Our experience helps navigate local constraints like slopes, trees, and access while keeping projects moving efficiently.With properly prepared plans, many homeowners are seeing approvals within statutory timelines. If you searched “ADU contractor near me” and are considering a guest house for family, a private home office, aging-in-place solution, or rental income in the Portola Valley market, you’re in the right place. With 24 years of experience, an A+ BBB rating, and Diamond Certified recognition for 18 years, we’re proud to be a trusted ADU builder and garage conversion contractor serving Portola Valley and San Mateo County.

Types of ADUs We Build

Attached ADU

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Attached ADUs are newly constructed additions connected to the main home, designed to integrate naturally with the existing structure while featuring a private, separate entrance.

Detatched ADU

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Detached ADUs are newly built standalone backyard structures designed as fully independent living spaces that provide maximum privacy.

ADU Conversion

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ADU Conversions transform an existing garage, attic, basement, or interior space into a fully functional living unit with its own private entrance.

What are your plans?

We would love to hear about them. We have over 24 years experience in ADUs and conversions. Let's team up and make your dream come true.

What Our Clients Are Saying!

The Benefits of an ADU in Portola Valley

  • Personal Workspace or Gym

    Since there's not owner occupancy requirements in Palo Alto, you can use your ADU as a studio, gym or any hobbies you're into!
  • AirBNB Rental Income

    Start making $2,500-$5,000/month renting out your ADU with apps like AirBNB, especially in Silicon Valley / Bay Area!

  • Boost Property Value

    Want to boost your property value by 20-50%? They're recognized as potential for separate income-producing potential, which makes your home even more desirable.

  • Keep Family Close

    For guests, parents, in-laws or adult children who can't afford Palto Alto home prices that keep increasing. This is a great alternative.

Take a 3D Tour of Our Past Projects!

Morgan Hill New Home Remodel Virtual Tour

Ralph

Morgan Hill Remodel

Full custom home construction in Sunnyvale, Bay Area.

Eagle Dr

Sunnyvale Home Remodel

Beautiful kitchen remodel with wooden cabinets and island in San Jose.

Englewood

San Jose Home Addition

Incredible custom home built in Palo Alto.

Webster

Palo Alto Remodel

Bay Area modern kitchen with wooden cabinets and new flooring.

Frontenac

Sunnyvale Home Remodel

Need an ADU?

Sigura Construction is your trusted ADU contractor serving not just Portola Valley, but San Mateo, Santa Clara, and the greater Bay Area.