ADU Contractors near Mill Valley, CA
DSA Architects
1107 Virginia Street, Berkeley, CA 94702
14.3 miles
DSA Architects designed an 850 sq. ft. second-floor ADU in Berkeley Hills for multi-generational living. Features 2 beds, 1 bath, open layout, Tilden Park views, roof deck, solar PV, heat pumps, and gray-water system.
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Spruce ADU Builders Union City
3909 Smith Street, Union City, CA 94587
33.2 miles
Spruce ADU Builders is a licensed ADU contractor in Union City offering expert accessory dwelling unit construction. Services include granny flats, in-law suites, and custom ADUs with free consultations, transparent pricing, and a 100% satisfaction guarantee.
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Excellent Home Remodeling
1310 Alma Avenue, Walnut Creek, CA 94596
26 miles
Excellent Home Remodeling offers professional home addition services in Sonoma, helping homeowners expand living spaces, add bedrooms, bathrooms, home offices, or in-law suites. They handle planning and execution tailored to each property's needs.
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Adria Design + Build
648 Paco Drive, Los Altos, CA 94024
44.1 miles
We guide you through design options and material choices, taking precise measurements to create a custom plan that perfectly fits your property. This careful planning ensures that your new ADU will seamlessly blend with your existing space and meet all your functional needs.
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Second Dwellings
100 Higgins Canyon Road, Half Moon Bay, CA 94019
33.4 miles
Vought Construction
734 Gilman Street, Berkeley, CA 94710
13.4 miles
Imagine the possibilities that a beautifully crafted ADU (accessory dwelling unit) brings to your Berkeley or Bay Area property. Whether it’s creating a cozy retreat for guests, a comfortable living space for family members, or an additional source of income through rental, design your ADU to enrich your life.
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J.A. Meija Construction
5430 Commerce Boulevard, Rohnert Park, CA 94928
31.9 miles
J.A. Mejia Construction is a licensed ADU builder & home addition contractor in Sonoma County & the Bay Area. Services include detached ADUs, garage conversions, in-law suites & second-story additions in Santa Rosa, Petaluma & beyond.
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Romy Construction Inc
612 Miller Avenue, South San Francisco, CA 94080
18.8 miles
North Bay ADU & Additions
1475 North Street, Santa Rosa, CA 95404
38.8 miles
North Bay ADU & Additions is a trusted ADU builder serving the North Bay area, specializing in accessory dwelling units and home additions. They offer planning, construction, and permit consultation to help homeowners boost property value and rental income.
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Regency Construnction & Remodeling BA
The Paramount, 95 3rd St, San Francisco, CA 94103
11.4 miles
Regency Construction & Remodeling BA is a San Francisco ADU contractor offering new builds, space conversions, and prefab ADU solutions. They handle design to completion, manage permits, and ensure compliance with local zoning laws.
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Hilario Construction
Santa Rosa, CA 95405
37.4 miles
Hilario Construction is a Santa Rosa ADU contractor offering full-service accessory dwelling unit construction, including permits, design, and turnkey delivery. Serving Santa Rosa, Windsor, and Petaluma, they build detached ADUs, granny flats, and in-law suites compliant with California ADU laws.
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S.D White Construction Inc
1151 Hensley Street, Richmond, CA 94801
10 miles
S.D White Construction Inc, a licensed Bay Area ADU contractor with 20+ years experience, builds detached, attached, garage conversion & above-garage ADUs in Richmond, CA. Full-service from design & permits to final inspection, completed in 3–5 months.
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Atlas Construction
101 Jefferson Drive, Menlo Park, CA 94025
35.6 miles
Atlas General Construction delivers complete ADU construction for detached, attached, and converted structures. Our team manages every phase of development including zoning research, architectural coordination, structural engineering, Title 24 compliance, permit processing, foundation work, framing, roofing, plumbing, electrical systems, HVAC installation, interior finishes, and final inspections.
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Haus+
Corte Madera, CA 94925
1.4 miles
Haus+ is a Bay Area ADU builder offering turnkey accessory dwelling units for California homeowners. They handle design, permitting, and construction using a panelized hybrid method, with all-inclusive upfront pricing and in-house financing available.
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Bay Villa Builders
36007 Bayonne Drive, Newark, CA 94560
37.2 miles
Bay Villa Builders brings over 50 years of combined experience in crafting expertly designed ADUs that enhance both your home's functionality and its value. An Accessory Dwelling Unit, or ADU, serves as an additional living space on your property.
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Other cities in California
What you need to know
Building ADUs in Mill Valley: Navigating a Hillside Community
Mill Valley, nestled in the scenic hills of Marin County just north of San Francisco, presents a unique set of challenges and opportunities for ADU contractors. Known for its dense redwood forests, steep terrain, and architecturally distinctive homes, Mill Valley requires experienced ADU professionals who understand the complexities of building on hillside lots, working around mature trees, and complying with both California state ADU laws and the City of Mill Valley's local regulations.
Local Regulations and Permitting for ADUs in Mill Valley
Mill Valley falls under the jurisdiction of the City of Mill Valley Community Development Department, which oversees ADU permitting. While California state law (AB 68, AB 881, and SB 13) has significantly streamlined ADU approvals statewide, Mill Valley still enforces specific local standards that contractors must navigate carefully. Key considerations include:
- Fire hazard zones: Much of Mill Valley is located within a Very High Fire Hazard Severity Zone (VHFHSZ), requiring ADUs to meet strict fire-resistant construction standards, including ember-resistant vents, Class A roofing, and defensible space requirements.
- Tree protection ordinances: Mill Valley has strong protections for heritage and protected trees. ADU contractors must often work around significant root zones and may need arborist reports before breaking ground.
- Steep slope regulations: Many parcels in Mill Valley have slopes exceeding 15–25%, which can trigger additional geotechnical studies and grading permits.
- Setback and height requirements: Local zoning may impose setback rules and height limits that vary by zone, requiring careful site analysis before design begins.
Types of ADUs Commonly Built in Mill Valley
Given the nature of Mill Valley's existing housing stock — largely single-family homes with garages, basements, or detached structures — the most popular ADU types in the area include:
- Garage conversion ADUs – Converting an existing attached or detached garage into a living unit is a cost-effective option popular in Mill Valley neighborhoods.
- Detached ADUs – Standalone units built in backyards, though hillside lots often require custom foundation solutions such as pier-and-grade beam systems.
- Junior ADUs (JADUs) – Units of up to 500 square feet created within the existing footprint of a primary residence.
Choosing the Right ADU Contractor in Mill Valley
Selecting a qualified ADU contractor in Mill Valley means finding a professional with demonstrated experience in Marin County's regulatory environment. The right contractor will be familiar with the Mill Valley Building Division, understand fire-safe construction methods, and have relationships with local engineers and arborists. Look for contractors who are licensed by the California Contractors State License Board (CSLB) and who have a proven portfolio of completed ADU projects in hillside communities similar to Mill Valley.
Investing in an ADU in Mill Valley can significantly increase your property's value and provide rental income in one of the most desirable communities in the San Francisco Bay Area. With the right contractor, the process can be smooth, code-compliant, and tailored to the unique character of your Mill Valley property.